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[Linux-stable-mirror] Patch "arm64: fpsimd: Prevent registers leaking from dead tasks" has been added to the 4.14-stable tree

by gregkh＠linuxfoundation.org

This is a note to let you know that I've just added the patch titled arm64: fpsimd: Prevent registers leaking from dead tasks to the 4.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum… The filename of the patch is: arm64-fpsimd-prevent-registers-leaking-from-dead-tasks.patch and it can be found in the queue-4.14 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable(a)vger.kernel.org> know about it. >From 071b6d4a5d343046f253a5a8835d477d93992002 Mon Sep 17 00:00:00 2001 From: Dave Martin <Dave.Martin(a)arm.com> Date: Tue, 5 Dec 2017 14:56:42 +0000 Subject: arm64: fpsimd: Prevent registers leaking from dead tasks From: Dave Martin <Dave.Martin(a)arm.com> commit 071b6d4a5d343046f253a5a8835d477d93992002 upstream. Currently, loading of a task's fpsimd state into the CPU registers is skipped if that task's state is already present in the registers of that CPU. However, the code relies on the struct fpsimd_state * (and by extension struct task_struct *) to unambiguously identify a task. There is a particular case in which this doesn't work reliably: when a task exits, its task_struct may be recycled to describe a new task. Consider the following scenario: 1) Task P loads its fpsimd state onto cpu C. per_cpu(fpsimd_last_state, C) := P; P->thread.fpsimd_state.cpu := C; 2) Task X is scheduled onto C and loads its fpsimd state on C. per_cpu(fpsimd_last_state, C) := X; X->thread.fpsimd_state.cpu := C; 3) X exits, causing X's task_struct to be freed. 4) P forks a new child T, which obtains X's recycled task_struct. T == X. T->thread.fpsimd_state.cpu == C (inherited from P). 5) T is scheduled on C. T's fpsimd state is not loaded, because per_cpu(fpsimd_last_state, C) == T (== X) && T->thread.fpsimd_state.cpu == C. (This is the check performed by fpsimd_thread_switch().) So, T gets X's registers because the last registers loaded onto C were those of X, in (2). This patch fixes the problem by ensuring that the sched-in check fails in (5): fpsimd_flush_task_state(T) is called when T is forked, so that T->thread.fpsimd_state.cpu == C cannot be true. This relies on the fact that T is not schedulable until after copy_thread() completes. Once T's fpsimd state has been loaded on some CPU C there may still be other cpus D for which per_cpu(fpsimd_last_state, D) == &X->thread.fpsimd_state. But D is necessarily != C in this case, and the check in (5) must fail. An alternative fix would be to do refcounting on task_struct. This would result in each CPU holding a reference to the last task whose fpsimd state was loaded there. It's not clear whether this is preferable, and it involves higher overhead than the fix proposed in this patch. It would also move all the task_struct freeing work into the context switch critical section, or otherwise some deferred cleanup mechanism would need to be introduced, neither of which seems obviously justified. Fixes: 005f78cd8849 ("arm64: defer reloading a task's FPSIMD state to userland resume") Signed-off-by: Dave Martin <Dave.Martin(a)arm.com> Reviewed-by: Ard Biesheuvel <ard.biesheuvel(a)linaro.org> [will: word-smithed the comment so it makes more sense] Signed-off-by: Will Deacon <will.deacon(a)arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> --- arch/arm64/kernel/process.c | 9 +++++++++ 1 file changed, 9 insertions(+) --- a/arch/arm64/kernel/process.c +++ b/arch/arm64/kernel/process.c @@ -258,6 +258,15 @@ int copy_thread(unsigned long clone_flag memset(&p->thread.cpu_context, 0, sizeof(struct cpu_context)); + /* + * In case p was allocated the same task_struct pointer as some + * other recently-exited task, make sure p is disassociated from + * any cpu that may have run that now-exited task recently. + * Otherwise we could erroneously skip reloading the FPSIMD + * registers for p. + */ + fpsimd_flush_task_state(p); + if (likely(!(p->flags & PF_KTHREAD))) { *childregs = *current_pt_regs(); childregs->regs[0] = 0; Patches currently in stable-queue which might be from Dave.Martin(a)arm.com are queue-4.14/arm64-fpsimd-prevent-registers-leaking-from-dead-tasks.patch

7 years, 9 months

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[Linux-stable-mirror] Patch "ALSA: usb-audio: Fix out-of-bound error" has been added to the 4.14-stable tree

by gregkh＠linuxfoundation.org

This is a note to let you know that I've just added the patch titled ALSA: usb-audio: Fix out-of-bound error to the 4.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum… The filename of the patch is: alsa-usb-audio-fix-out-of-bound-error.patch and it can be found in the queue-4.14 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable(a)vger.kernel.org> know about it. >From 251552a2b0d454badc8f486e6d79100970c744b0 Mon Sep 17 00:00:00 2001 From: Jaejoong Kim <climbbb.kim(a)gmail.com> Date: Mon, 4 Dec 2017 15:31:48 +0900 Subject: ALSA: usb-audio: Fix out-of-bound error From: Jaejoong Kim <climbbb.kim(a)gmail.com> commit 251552a2b0d454badc8f486e6d79100970c744b0 upstream. The snd_usb_copy_string_desc() retrieves the usb string corresponding to the index number through the usb_string(). The problem is that the usb_string() returns the length of the string (>= 0) when successful, but it can also return a negative value about the error case or status of usb_control_msg(). If iClockSource is '0' as shown below, usb_string() will returns -EINVAL. This will result in '0' being inserted into buf[-22], and the following KASAN out-of-bound error message will be output. AudioControl Interface Descriptor: bLength 8 bDescriptorType 36 bDescriptorSubtype 10 (CLOCK_SOURCE) bClockID 1 bmAttributes 0x07 Internal programmable Clock (synced to SOF) bmControls 0x07 Clock Frequency Control (read/write) Clock Validity Control (read-only) bAssocTerminal 0 iClockSource 0 To fix it, check usb_string()'return value and bail out. ================================================================== BUG: KASAN: stack-out-of-bounds in parse_audio_unit+0x1327/0x1960 [snd_usb_audio] Write of size 1 at addr ffff88007e66735a by task systemd-udevd/18376 CPU: 0 PID: 18376 Comm: systemd-udevd Not tainted 4.13.0+ #3 Hardware name: LG Electronics 15N540-RFLGL/White Tip Mountain, BIOS 15N5 Call Trace: dump_stack+0x63/0x8d print_address_description+0x70/0x290 ? parse_audio_unit+0x1327/0x1960 [snd_usb_audio] kasan_report+0x265/0x350 __asan_store1+0x4a/0x50 parse_audio_unit+0x1327/0x1960 [snd_usb_audio] ? save_stack+0xb5/0xd0 ? save_stack_trace+0x1b/0x20 ? save_stack+0x46/0xd0 ? kasan_kmalloc+0xad/0xe0 ? kmem_cache_alloc_trace+0xff/0x230 ? snd_usb_create_mixer+0xb0/0x4b0 [snd_usb_audio] ? usb_audio_probe+0x4de/0xf40 [snd_usb_audio] ? usb_probe_interface+0x1f5/0x440 ? driver_probe_device+0x3ed/0x660 ? build_feature_ctl+0xb10/0xb10 [snd_usb_audio] ? save_stack_trace+0x1b/0x20 ? init_object+0x69/0xa0 ? snd_usb_find_csint_desc+0xa8/0xf0 [snd_usb_audio] snd_usb_mixer_controls+0x1dc/0x370 [snd_usb_audio] ? build_audio_procunit+0x890/0x890 [snd_usb_audio] ? snd_usb_create_mixer+0xb0/0x4b0 [snd_usb_audio] ? kmem_cache_alloc_trace+0xff/0x230 ? usb_ifnum_to_if+0xbd/0xf0 snd_usb_create_mixer+0x25b/0x4b0 [snd_usb_audio] ? snd_usb_create_stream+0x255/0x2c0 [snd_usb_audio] usb_audio_probe+0x4de/0xf40 [snd_usb_audio] ? snd_usb_autosuspend.part.7+0x30/0x30 [snd_usb_audio] ? __pm_runtime_idle+0x90/0x90 ? kernfs_activate+0xa6/0xc0 ? usb_match_one_id_intf+0xdc/0x130 ? __pm_runtime_set_status+0x2d4/0x450 usb_probe_interface+0x1f5/0x440 Signed-off-by: Jaejoong Kim <climbbb.kim(a)gmail.com> Signed-off-by: Takashi Iwai <tiwai(a)suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> --- sound/usb/mixer.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/sound/usb/mixer.c +++ b/sound/usb/mixer.c @@ -204,6 +204,10 @@ static int snd_usb_copy_string_desc(stru int index, char *buf, int maxlen) { int len = usb_string(state->chip->dev, index, buf, maxlen - 1); + + if (len < 0) + return 0; + buf[len] = 0; return len; } Patches currently in stable-queue which might be from climbbb.kim(a)gmail.com are queue-4.14/alsa-usb-audio-add-check-return-value-for-usb_string.patch queue-4.14/alsa-usb-audio-fix-out-of-bound-error.patch

7 years, 9 months

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[Linux-stable-mirror] Patch "arm: KVM: Fix VTTBR_BADDR_MASK BUG_ON off-by-one" has been added to the 4.14-stable tree

by gregkh＠linuxfoundation.org

This is a note to let you know that I've just added the patch titled arm: KVM: Fix VTTBR_BADDR_MASK BUG_ON off-by-one to the 4.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum… The filename of the patch is: arm-kvm-fix-vttbr_baddr_mask-bug_on-off-by-one.patch and it can be found in the queue-4.14 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable(a)vger.kernel.org> know about it. >From 5553b142be11e794ebc0805950b2e8313f93d718 Mon Sep 17 00:00:00 2001 From: Marc Zyngier <marc.zyngier(a)arm.com> Date: Thu, 16 Nov 2017 17:58:21 +0000 Subject: arm: KVM: Fix VTTBR_BADDR_MASK BUG_ON off-by-one From: Marc Zyngier <marc.zyngier(a)arm.com> commit 5553b142be11e794ebc0805950b2e8313f93d718 upstream. VTTBR_BADDR_MASK is used to sanity check the size and alignment of the VTTBR address. It seems to currently be off by one, thereby only allowing up to 39-bit addresses (instead of 40-bit) and also insufficiently checking the alignment. This patch fixes it. This patch is the 32bit pendent of Kristina's arm64 fix, and she deserves the actual kudos for pinpointing that one. Fixes: f7ed45be3ba52 ("KVM: ARM: World-switch implementation") Reported-by: Kristina Martsenko <kristina.martsenko(a)arm.com> Reviewed-by: Christoffer Dall <christoffer.dall(a)linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier(a)arm.com> Signed-off-by: Christoffer Dall <christoffer.dall(a)linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> --- arch/arm/include/asm/kvm_arm.h | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) --- a/arch/arm/include/asm/kvm_arm.h +++ b/arch/arm/include/asm/kvm_arm.h @@ -161,8 +161,7 @@ #else #define VTTBR_X (5 - KVM_T0SZ) #endif -#define VTTBR_BADDR_SHIFT (VTTBR_X - 1) -#define VTTBR_BADDR_MASK (((_AC(1, ULL) << (40 - VTTBR_X)) - 1) << VTTBR_BADDR_SHIFT) +#define VTTBR_BADDR_MASK (((_AC(1, ULL) << (40 - VTTBR_X)) - 1) << VTTBR_X) #define VTTBR_VMID_SHIFT _AC(48, ULL) #define VTTBR_VMID_MASK(size) (_AT(u64, (1 << size) - 1) << VTTBR_VMID_SHIFT) Patches currently in stable-queue which might be from marc.zyngier(a)arm.com are queue-4.14/arm-kvm-fix-vttbr_baddr_mask-bug_on-off-by-one.patch queue-4.14/kvm-arm-arm64-vgic-its-check-result-of-allocation-before-use.patch queue-4.14/kvm-arm-arm64-vgic-preserve-the-revious-read-from-the-pending-table.patch queue-4.14/kvm-arm-arm64-vgic-irqfd-fix-msi-entry-allocation.patch queue-4.14/bus-arm-cci-fix-use-of-smp_processor_id-in-preemptible-context.patch queue-4.14/arm64-kvm-fix-vttbr_baddr_mask-bug_on-off-by-one.patch queue-4.14/bus-arm-ccn-fix-use-of-smp_processor_id-in-preemptible-context.patch

7 years, 9 months

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[Linux-stable-mirror] Patch "ALSA: pcm: prevent UAF in snd_pcm_info" has been added to the 4.14-stable tree

by gregkh＠linuxfoundation.org

This is a note to let you know that I've just added the patch titled ALSA: pcm: prevent UAF in snd_pcm_info to the 4.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum… The filename of the patch is: alsa-pcm-prevent-uaf-in-snd_pcm_info.patch and it can be found in the queue-4.14 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable(a)vger.kernel.org> know about it. >From 362bca57f5d78220f8b5907b875961af9436e229 Mon Sep 17 00:00:00 2001 From: Robb Glasser <rglasser(a)google.com> Date: Tue, 5 Dec 2017 09:16:55 -0800 Subject: ALSA: pcm: prevent UAF in snd_pcm_info From: Robb Glasser <rglasser(a)google.com> commit 362bca57f5d78220f8b5907b875961af9436e229 upstream. When the device descriptor is closed, the `substream->runtime` pointer is freed. But another thread may be in the ioctl handler, case SNDRV_CTL_IOCTL_PCM_INFO. This case calls snd_pcm_info_user() which calls snd_pcm_info() which accesses the now freed `substream->runtime`. Note: this fixes CVE-2017-0861 Signed-off-by: Robb Glasser <rglasser(a)google.com> Signed-off-by: Nick Desaulniers <ndesaulniers(a)google.com> Signed-off-by: Takashi Iwai <tiwai(a)suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> --- sound/core/pcm.c | 2 ++ 1 file changed, 2 insertions(+) --- a/sound/core/pcm.c +++ b/sound/core/pcm.c @@ -153,7 +153,9 @@ static int snd_pcm_control_ioctl(struct err = -ENXIO; goto _error; } + mutex_lock(&pcm->open_mutex); err = snd_pcm_info_user(substream, info); + mutex_unlock(&pcm->open_mutex); _error: mutex_unlock(&register_mutex); return err; Patches currently in stable-queue which might be from rglasser(a)google.com are queue-4.14/alsa-pcm-prevent-uaf-in-snd_pcm_info.patch

7 years, 9 months

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[Linux-stable-mirror] Patch "ALSA: usb-audio: Add check return value for usb_string()" has been added to the 4.14-stable tree

by gregkh＠linuxfoundation.org

This is a note to let you know that I've just added the patch titled ALSA: usb-audio: Add check return value for usb_string() to the 4.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum… The filename of the patch is: alsa-usb-audio-add-check-return-value-for-usb_string.patch and it can be found in the queue-4.14 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable(a)vger.kernel.org> know about it. >From 89b89d121ffcf8d9546633b98ded9d18b8f75891 Mon Sep 17 00:00:00 2001 From: Jaejoong Kim <climbbb.kim(a)gmail.com> Date: Mon, 4 Dec 2017 15:31:49 +0900 Subject: ALSA: usb-audio: Add check return value for usb_string() From: Jaejoong Kim <climbbb.kim(a)gmail.com> commit 89b89d121ffcf8d9546633b98ded9d18b8f75891 upstream. snd_usb_copy_string_desc() returns zero if usb_string() fails. In case of failure, we need to check the snd_usb_copy_string_desc()'s return value and add an exception case Signed-off-by: Jaejoong Kim <climbbb.kim(a)gmail.com> Signed-off-by: Takashi Iwai <tiwai(a)suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> --- sound/usb/mixer.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) --- a/sound/usb/mixer.c +++ b/sound/usb/mixer.c @@ -2178,13 +2178,14 @@ static int parse_audio_selector_unit(str if (len) ; else if (nameid) - snd_usb_copy_string_desc(state, nameid, kctl->id.name, + len = snd_usb_copy_string_desc(state, nameid, kctl->id.name, sizeof(kctl->id.name)); - else { + else len = get_term_name(state, &state->oterm, kctl->id.name, sizeof(kctl->id.name), 0); - if (!len) - strlcpy(kctl->id.name, "USB", sizeof(kctl->id.name)); + + if (!len) { + strlcpy(kctl->id.name, "USB", sizeof(kctl->id.name)); if (desc->bDescriptorSubtype == UAC2_CLOCK_SELECTOR) append_ctl_name(kctl, " Clock Source"); Patches currently in stable-queue which might be from climbbb.kim(a)gmail.com are queue-4.14/alsa-usb-audio-add-check-return-value-for-usb_string.patch queue-4.14/alsa-usb-audio-fix-out-of-bound-error.patch

7 years, 9 months

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[Linux-stable-mirror] Patch "ALSA: seq: Remove spurious WARN_ON() at timer check" has been added to the 4.14-stable tree

by gregkh＠linuxfoundation.org

This is a note to let you know that I've just added the patch titled ALSA: seq: Remove spurious WARN_ON() at timer check to the 4.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum… The filename of the patch is: alsa-seq-remove-spurious-warn_on-at-timer-check.patch and it can be found in the queue-4.14 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable(a)vger.kernel.org> know about it. >From 43a3542870328601be02fcc9d27b09db467336ef Mon Sep 17 00:00:00 2001 From: Takashi Iwai <tiwai(a)suse.de> Date: Thu, 30 Nov 2017 10:08:28 +0100 Subject: ALSA: seq: Remove spurious WARN_ON() at timer check From: Takashi Iwai <tiwai(a)suse.de> commit 43a3542870328601be02fcc9d27b09db467336ef upstream. The use of snd_BUG_ON() in ALSA sequencer timer may lead to a spurious WARN_ON() when a slave timer is deployed as its backend and a corresponding master timer stops meanwhile. The symptom was triggered by syzkaller spontaneously. Since the NULL timer is valid there, rip off snd_BUG_ON(). Reported-by: syzbot <syzkaller(a)googlegroups.com> Signed-off-by: Takashi Iwai <tiwai(a)suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> --- sound/core/seq/seq_timer.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/sound/core/seq/seq_timer.c +++ b/sound/core/seq/seq_timer.c @@ -355,7 +355,7 @@ static int initialize_timer(struct snd_s unsigned long freq; t = tmr->timeri->timer; - if (snd_BUG_ON(!t)) + if (!t) return -EINVAL; freq = tmr->preferred_resolution; Patches currently in stable-queue which might be from tiwai(a)suse.de are queue-4.14/alsa-seq-remove-spurious-warn_on-at-timer-check.patch queue-4.14/alsa-pcm-prevent-uaf-in-snd_pcm_info.patch queue-4.14/alsa-usb-audio-add-check-return-value-for-usb_string.patch queue-4.14/alsa-hda-realtek-new-codec-support-for-alc257.patch queue-4.14/alsa-usb-audio-fix-out-of-bound-error.patch

7 years, 9 months

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[Linux-stable-mirror] Patch "ALSA: hda/realtek - New codec support for ALC257" has been added to the 4.14-stable tree

by gregkh＠linuxfoundation.org

This is a note to let you know that I've just added the patch titled ALSA: hda/realtek - New codec support for ALC257 to the 4.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum… The filename of the patch is: alsa-hda-realtek-new-codec-support-for-alc257.patch and it can be found in the queue-4.14 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable(a)vger.kernel.org> know about it. >From f429e7e494afaded76e62c6f98211a635aa03098 Mon Sep 17 00:00:00 2001 From: Kailang Yang <kailang(a)realtek.com> Date: Tue, 5 Dec 2017 15:38:24 +0800 Subject: ALSA: hda/realtek - New codec support for ALC257 From: Kailang Yang <kailang(a)realtek.com> commit f429e7e494afaded76e62c6f98211a635aa03098 upstream. Add new support for ALC257 codec. [ It's supposed to be almost equivalent with other ALC25x variants, just adding another type and id -- tiwai ] Signed-off-by: Kailang Yang <kailang(a)realtek.com> Signed-off-by: Takashi Iwai <tiwai(a)suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> --- sound/pci/hda/patch_realtek.c | 8 ++++++++ 1 file changed, 8 insertions(+) --- a/sound/pci/hda/patch_realtek.c +++ b/sound/pci/hda/patch_realtek.c @@ -330,6 +330,7 @@ static void alc_fill_eapd_coef(struct hd case 0x10ec0236: case 0x10ec0255: case 0x10ec0256: + case 0x10ec0257: case 0x10ec0282: case 0x10ec0283: case 0x10ec0286: @@ -2749,6 +2750,7 @@ enum { ALC269_TYPE_ALC298, ALC269_TYPE_ALC255, ALC269_TYPE_ALC256, + ALC269_TYPE_ALC257, ALC269_TYPE_ALC215, ALC269_TYPE_ALC225, ALC269_TYPE_ALC294, @@ -2782,6 +2784,7 @@ static int alc269_parse_auto_config(stru case ALC269_TYPE_ALC298: case ALC269_TYPE_ALC255: case ALC269_TYPE_ALC256: + case ALC269_TYPE_ALC257: case ALC269_TYPE_ALC215: case ALC269_TYPE_ALC225: case ALC269_TYPE_ALC294: @@ -6839,6 +6842,10 @@ static int patch_alc269(struct hda_codec spec->gen.mixer_nid = 0; /* ALC256 does not have any loopback mixer path */ alc_update_coef_idx(codec, 0x36, 1 << 13, 1 << 5); /* Switch pcbeep path to Line in path*/ break; + case 0x10ec0257: + spec->codec_variant = ALC269_TYPE_ALC257; + spec->gen.mixer_nid = 0; + break; case 0x10ec0215: case 0x10ec0285: case 0x10ec0289: @@ -7886,6 +7893,7 @@ static const struct hda_device_id snd_hd HDA_CODEC_ENTRY(0x10ec0236, "ALC236", patch_alc269), HDA_CODEC_ENTRY(0x10ec0255, "ALC255", patch_alc269), HDA_CODEC_ENTRY(0x10ec0256, "ALC256", patch_alc269), + HDA_CODEC_ENTRY(0x10ec0257, "ALC257", patch_alc269), HDA_CODEC_ENTRY(0x10ec0260, "ALC260", patch_alc260), HDA_CODEC_ENTRY(0x10ec0262, "ALC262", patch_alc262), HDA_CODEC_ENTRY(0x10ec0267, "ALC267", patch_alc268), Patches currently in stable-queue which might be from kailang(a)realtek.com are queue-4.14/alsa-hda-realtek-new-codec-support-for-alc257.patch

7 years, 9 months

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[Linux-stable-mirror] FAILED: patch "[PATCH] bus: arm-ccn: Fix use of smp_processor_id() in preemptible" failed to apply to 4.4-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 4.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From b18c2b9487d8e797fc0a757e57ac3645348c5fba Mon Sep 17 00:00:00 2001 From: Marc Zyngier <marc.zyngier(a)arm.com> Date: Tue, 3 Oct 2017 18:14:12 +0100 Subject: [PATCH] bus: arm-ccn: Fix use of smp_processor_id() in preemptible context Booting a DEBUG_PREEMPT enabled kernel on a CCN-based system results in the following splat: [...] arm-ccn e8000000.ccn: No access to interrupts, using timer. BUG: using smp_processor_id() in preemptible [00000000] code: swapper/0/1 caller is debug_smp_processor_id+0x1c/0x28 CPU: 1 PID: 1 Comm: swapper/0 Not tainted 4.13.0 #6111 Hardware name: AMD Seattle/Seattle, BIOS 17:08:23 Jun 26 2017 Call trace: [<ffff000008089e78>] dump_backtrace+0x0/0x278 [<ffff00000808a22c>] show_stack+0x24/0x30 [<ffff000008bc3bc4>] dump_stack+0x8c/0xb0 [<ffff00000852b534>] check_preemption_disabled+0xfc/0x100 [<ffff00000852b554>] debug_smp_processor_id+0x1c/0x28 [<ffff000008551bd8>] arm_ccn_probe+0x358/0x4f0 [...] as we use smp_processor_id() in the wrong context. Turn this into a get_cpu()/put_cpu() that extends over the CPU hotplug registration, making sure that we don't race against a CPU down operation. Signed-off-by: Marc Zyngier <marc.zyngier(a)arm.com> Acked-by: Mark Rutland <mark.rutland(a)arm.com> Cc: stable(a)vger.kernel.org # 4.2+ Signed-off-by: Pawel Moll <pawel.moll(a)arm.com> diff --git a/drivers/bus/arm-ccn.c b/drivers/bus/arm-ccn.c index bbc1a2ef9639..508a1a389b7e 100644 --- a/drivers/bus/arm-ccn.c +++ b/drivers/bus/arm-ccn.c @@ -1300,7 +1300,7 @@ static int arm_ccn_pmu_init(struct arm_ccn *ccn) } /* Pick one CPU which we will use to collect data from CCN... */ - cpumask_set_cpu(smp_processor_id(), &ccn->dt.cpu); + cpumask_set_cpu(get_cpu(), &ccn->dt.cpu); /* Also make sure that the overflow interrupt is handled by this CPU */ if (ccn->irq) { @@ -1317,10 +1317,12 @@ static int arm_ccn_pmu_init(struct arm_ccn *ccn) cpuhp_state_add_instance_nocalls(CPUHP_AP_PERF_ARM_CCN_ONLINE, &ccn->dt.node); + put_cpu(); return 0; error_pmu_register: error_set_affinity: + put_cpu(); error_choose_name: ida_simple_remove(&arm_ccn_pmu_ida, ccn->dt.id); for (i = 0; i < ccn->num_xps; i++)

7 years, 9 months

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[Linux-stable-mirror] FAILED: patch "[PATCH] bus: arm-ccn: Check memory allocation failure" failed to apply to 3.18-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 3.18-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 24771179c5c138f0ea3ef88b7972979f62f2d5db Mon Sep 17 00:00:00 2001 From: Christophe JAILLET <christophe.jaillet(a)wanadoo.fr> Date: Sun, 27 Aug 2017 11:06:50 +0100 Subject: [PATCH] bus: arm-ccn: Check memory allocation failure Check memory allocation failures and return -ENOMEM in such cases This avoids a potential NULL pointer dereference. Signed-off-by: Christophe JAILLET <christophe.jaillet(a)wanadoo.fr> Acked-by: Scott Branden <scott.branden(a)broadcom.com> Cc: stable(a)vger.kernel.org # 3.17+ Signed-off-by: Pawel Moll <pawel.moll(a)arm.com> diff --git a/drivers/bus/arm-ccn.c b/drivers/bus/arm-ccn.c index 7625bf762acb..a7951662f85b 100644 --- a/drivers/bus/arm-ccn.c +++ b/drivers/bus/arm-ccn.c @@ -1271,6 +1271,10 @@ static int arm_ccn_pmu_init(struct arm_ccn *ccn) int len = snprintf(NULL, 0, "ccn_%d", ccn->dt.id); name = devm_kzalloc(ccn->dev, len + 1, GFP_KERNEL); + if (!name) { + err = -ENOMEM; + goto error_choose_name; + } snprintf(name, len + 1, "ccn_%d", ccn->dt.id); } @@ -1319,6 +1323,7 @@ static int arm_ccn_pmu_init(struct arm_ccn *ccn) error_pmu_register: error_set_affinity: +error_choose_name: ida_simple_remove(&arm_ccn_pmu_ida, ccn->dt.id); for (i = 0; i < ccn->num_xps; i++) writel(0, ccn->xp[i].base + CCN_XP_DT_CONTROL);

7 years, 9 months

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[Linux-stable-mirror] FAILED: patch "[PATCH] bus: arm-ccn: Check memory allocation failure" failed to apply to 4.4-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 4.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 24771179c5c138f0ea3ef88b7972979f62f2d5db Mon Sep 17 00:00:00 2001 From: Christophe JAILLET <christophe.jaillet(a)wanadoo.fr> Date: Sun, 27 Aug 2017 11:06:50 +0100 Subject: [PATCH] bus: arm-ccn: Check memory allocation failure Check memory allocation failures and return -ENOMEM in such cases This avoids a potential NULL pointer dereference. Signed-off-by: Christophe JAILLET <christophe.jaillet(a)wanadoo.fr> Acked-by: Scott Branden <scott.branden(a)broadcom.com> Cc: stable(a)vger.kernel.org # 3.17+ Signed-off-by: Pawel Moll <pawel.moll(a)arm.com> diff --git a/drivers/bus/arm-ccn.c b/drivers/bus/arm-ccn.c index 7625bf762acb..a7951662f85b 100644 --- a/drivers/bus/arm-ccn.c +++ b/drivers/bus/arm-ccn.c @@ -1271,6 +1271,10 @@ static int arm_ccn_pmu_init(struct arm_ccn *ccn) int len = snprintf(NULL, 0, "ccn_%d", ccn->dt.id); name = devm_kzalloc(ccn->dev, len + 1, GFP_KERNEL); + if (!name) { + err = -ENOMEM; + goto error_choose_name; + } snprintf(name, len + 1, "ccn_%d", ccn->dt.id); } @@ -1319,6 +1323,7 @@ static int arm_ccn_pmu_init(struct arm_ccn *ccn) error_pmu_register: error_set_affinity: +error_choose_name: ida_simple_remove(&arm_ccn_pmu_ida, ccn->dt.id); for (i = 0; i < ccn->num_xps; i++) writel(0, ccn->xp[i].base + CCN_XP_DT_CONTROL);

7 years, 9 months

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[Linux-stable-mirror] FAILED: patch "[PATCH] bus: arm-cci: Fix use of smp_processor_id() in preemptible" failed to apply to 4.4-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 4.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 4608af8aa53e7f3922ddee695d023b7bcd5cb35b Mon Sep 17 00:00:00 2001 From: Marc Zyngier <marc.zyngier(a)arm.com> Date: Tue, 3 Oct 2017 18:14:13 +0100 Subject: [PATCH] bus: arm-cci: Fix use of smp_processor_id() in preemptible context The ARM CCI driver seem to be using smp_processor_id() in a preemptible context, which is likely to make a DEBUG_PREMPT kernel scream at boot time. Turn this into a get_cpu()/put_cpu() that extends over the CPU hotplug registration, making sure that we don't race against a CPU down operation. Signed-off-by: Marc Zyngier <marc.zyngier(a)arm.com> Acked-by: Mark Rutland <mark.rutland(a)arm.com> Cc: stable(a)vger.kernel.org # 4.2+ Signed-off-by: Pawel Moll <pawel.moll(a)arm.com> diff --git a/drivers/bus/arm-cci.c b/drivers/bus/arm-cci.c index 3c29d36702a8..5426c04fe24b 100644 --- a/drivers/bus/arm-cci.c +++ b/drivers/bus/arm-cci.c @@ -1755,14 +1755,17 @@ static int cci_pmu_probe(struct platform_device *pdev) raw_spin_lock_init(&cci_pmu->hw_events.pmu_lock); mutex_init(&cci_pmu->reserve_mutex); atomic_set(&cci_pmu->active_events, 0); - cpumask_set_cpu(smp_processor_id(), &cci_pmu->cpus); + cpumask_set_cpu(get_cpu(), &cci_pmu->cpus); ret = cci_pmu_init(cci_pmu, pdev); - if (ret) + if (ret) { + put_cpu(); return ret; + } cpuhp_state_add_instance_nocalls(CPUHP_AP_PERF_ARM_CCI_ONLINE, &cci_pmu->node); + put_cpu(); pr_info("ARM %s PMU driver probed", cci_pmu->model->name); return 0; }

7 years, 9 months

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[Linux-stable-mirror] FAILED: patch "[PATCH] KVM: arm/arm64: vgic-its: Preserve the revious read from the" failed to apply to 4.14-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 4.14-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 64afe6e9eb4841f35317da4393de21a047a883b3 Mon Sep 17 00:00:00 2001 From: Marc Zyngier <marc.zyngier(a)arm.com> Date: Thu, 16 Nov 2017 17:58:17 +0000 Subject: [PATCH] KVM: arm/arm64: vgic-its: Preserve the revious read from the pending table The current pending table parsing code assumes that we keep the previous read of the pending bits, but keep that variable in the current block, making sure it is discarded on each loop. We end-up using whatever is on the stack. Who knows, it might just be the right thing... Fixes: 33d3bc9556a7d ("KVM: arm64: vgic-its: Read initial LPI pending table") Cc: stable(a)vger.kernel.org # 4.8 Reported-by: AKASHI Takahiro <takahiro.akashi(a)linaro.org> Reviewed-by: Christoffer Dall <christoffer.dall(a)linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier(a)arm.com> Signed-off-by: Christoffer Dall <christoffer.dall(a)linaro.org> diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c index 1f761a9991e7..cb2d0a2dbe5a 100644 --- a/virt/kvm/arm/vgic/vgic-its.c +++ b/virt/kvm/arm/vgic/vgic-its.c @@ -421,6 +421,7 @@ static int its_sync_lpi_pending_table(struct kvm_vcpu *vcpu) u32 *intids; int nr_irqs, i; unsigned long flags; + u8 pendmask; nr_irqs = vgic_copy_lpi_list(vcpu, &intids); if (nr_irqs < 0) @@ -428,7 +429,6 @@ static int its_sync_lpi_pending_table(struct kvm_vcpu *vcpu) for (i = 0; i < nr_irqs; i++) { int byte_offset, bit_nr; - u8 pendmask; byte_offset = intids[i] / BITS_PER_BYTE; bit_nr = intids[i] % BITS_PER_BYTE;

7 years, 9 months

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[Linux-stable-mirror] FAILED: patch "[PATCH] KVM: arm/arm64: vgic-its: Preserve the revious read from the" failed to apply to 4.9-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 4.9-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 64afe6e9eb4841f35317da4393de21a047a883b3 Mon Sep 17 00:00:00 2001 From: Marc Zyngier <marc.zyngier(a)arm.com> Date: Thu, 16 Nov 2017 17:58:17 +0000 Subject: [PATCH] KVM: arm/arm64: vgic-its: Preserve the revious read from the pending table The current pending table parsing code assumes that we keep the previous read of the pending bits, but keep that variable in the current block, making sure it is discarded on each loop. We end-up using whatever is on the stack. Who knows, it might just be the right thing... Fixes: 33d3bc9556a7d ("KVM: arm64: vgic-its: Read initial LPI pending table") Cc: stable(a)vger.kernel.org # 4.8 Reported-by: AKASHI Takahiro <takahiro.akashi(a)linaro.org> Reviewed-by: Christoffer Dall <christoffer.dall(a)linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier(a)arm.com> Signed-off-by: Christoffer Dall <christoffer.dall(a)linaro.org> diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c index 1f761a9991e7..cb2d0a2dbe5a 100644 --- a/virt/kvm/arm/vgic/vgic-its.c +++ b/virt/kvm/arm/vgic/vgic-its.c @@ -421,6 +421,7 @@ static int its_sync_lpi_pending_table(struct kvm_vcpu *vcpu) u32 *intids; int nr_irqs, i; unsigned long flags; + u8 pendmask; nr_irqs = vgic_copy_lpi_list(vcpu, &intids); if (nr_irqs < 0) @@ -428,7 +429,6 @@ static int its_sync_lpi_pending_table(struct kvm_vcpu *vcpu) for (i = 0; i < nr_irqs; i++) { int byte_offset, bit_nr; - u8 pendmask; byte_offset = intids[i] / BITS_PER_BYTE; bit_nr = intids[i] % BITS_PER_BYTE;

7 years, 9 months

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[Linux-stable-mirror] FAILED: patch "[PATCH] arm: KVM: Fix VTTBR_BADDR_MASK BUG_ON off-by-one" failed to apply to 3.18-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 3.18-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 5553b142be11e794ebc0805950b2e8313f93d718 Mon Sep 17 00:00:00 2001 From: Marc Zyngier <marc.zyngier(a)arm.com> Date: Thu, 16 Nov 2017 17:58:21 +0000 Subject: [PATCH] arm: KVM: Fix VTTBR_BADDR_MASK BUG_ON off-by-one VTTBR_BADDR_MASK is used to sanity check the size and alignment of the VTTBR address. It seems to currently be off by one, thereby only allowing up to 39-bit addresses (instead of 40-bit) and also insufficiently checking the alignment. This patch fixes it. This patch is the 32bit pendent of Kristina's arm64 fix, and she deserves the actual kudos for pinpointing that one. Fixes: f7ed45be3ba52 ("KVM: ARM: World-switch implementation") Cc: <stable(a)vger.kernel.org> # 3.9 Reported-by: Kristina Martsenko <kristina.martsenko(a)arm.com> Reviewed-by: Christoffer Dall <christoffer.dall(a)linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier(a)arm.com> Signed-off-by: Christoffer Dall <christoffer.dall(a)linaro.org> diff --git a/arch/arm/include/asm/kvm_arm.h b/arch/arm/include/asm/kvm_arm.h index c8781450905b..3ab8b3781bfe 100644 --- a/arch/arm/include/asm/kvm_arm.h +++ b/arch/arm/include/asm/kvm_arm.h @@ -161,8 +161,7 @@ #else #define VTTBR_X (5 - KVM_T0SZ) #endif -#define VTTBR_BADDR_SHIFT (VTTBR_X - 1) -#define VTTBR_BADDR_MASK (((_AC(1, ULL) << (40 - VTTBR_X)) - 1) << VTTBR_BADDR_SHIFT) +#define VTTBR_BADDR_MASK (((_AC(1, ULL) << (40 - VTTBR_X)) - 1) << VTTBR_X) #define VTTBR_VMID_SHIFT _AC(48, ULL) #define VTTBR_VMID_MASK(size) (_AT(u64, (1 << size) - 1) << VTTBR_VMID_SHIFT)

7 years, 9 months

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[Linux-stable-mirror] FAILED: patch "[PATCH] arm: KVM: Fix VTTBR_BADDR_MASK BUG_ON off-by-one" failed to apply to 4.4-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 4.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 5553b142be11e794ebc0805950b2e8313f93d718 Mon Sep 17 00:00:00 2001 From: Marc Zyngier <marc.zyngier(a)arm.com> Date: Thu, 16 Nov 2017 17:58:21 +0000 Subject: [PATCH] arm: KVM: Fix VTTBR_BADDR_MASK BUG_ON off-by-one VTTBR_BADDR_MASK is used to sanity check the size and alignment of the VTTBR address. It seems to currently be off by one, thereby only allowing up to 39-bit addresses (instead of 40-bit) and also insufficiently checking the alignment. This patch fixes it. This patch is the 32bit pendent of Kristina's arm64 fix, and she deserves the actual kudos for pinpointing that one. Fixes: f7ed45be3ba52 ("KVM: ARM: World-switch implementation") Cc: <stable(a)vger.kernel.org> # 3.9 Reported-by: Kristina Martsenko <kristina.martsenko(a)arm.com> Reviewed-by: Christoffer Dall <christoffer.dall(a)linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier(a)arm.com> Signed-off-by: Christoffer Dall <christoffer.dall(a)linaro.org> diff --git a/arch/arm/include/asm/kvm_arm.h b/arch/arm/include/asm/kvm_arm.h index c8781450905b..3ab8b3781bfe 100644 --- a/arch/arm/include/asm/kvm_arm.h +++ b/arch/arm/include/asm/kvm_arm.h @@ -161,8 +161,7 @@ #else #define VTTBR_X (5 - KVM_T0SZ) #endif -#define VTTBR_BADDR_SHIFT (VTTBR_X - 1) -#define VTTBR_BADDR_MASK (((_AC(1, ULL) << (40 - VTTBR_X)) - 1) << VTTBR_BADDR_SHIFT) +#define VTTBR_BADDR_MASK (((_AC(1, ULL) << (40 - VTTBR_X)) - 1) << VTTBR_X) #define VTTBR_VMID_SHIFT _AC(48, ULL) #define VTTBR_VMID_MASK(size) (_AT(u64, (1 << size) - 1) << VTTBR_VMID_SHIFT)

7 years, 9 months

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[Linux-stable-mirror] FAILED: patch "[PATCH] drm/i915: Fix vblank timestamp/frame counter jumps on gen2" failed to apply to 4.9-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 4.9-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From a87e55f89f0b0dc541d89248a8445635936a3858 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= <ville.syrjala(a)linux.intel.com> Date: Wed, 29 Nov 2017 17:37:30 +0200 Subject: [PATCH] drm/i915: Fix vblank timestamp/frame counter jumps on gen2 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Previously I was under the impression that the scanline counter reads 0 when the pipe is off. Turns out that's not correct, and instead the scanline counter simply stops when the pipe stops, and it retains it's last value until the pipe starts up again, at which point the scanline counter jumps to vblank start. These jumps can cause the timestamp to jump backwards by one frame. Since we use the timestamps to guesstimage also the frame counter value on gen2, that would cause the frame counter to also jump backwards, which leads to a massice difference from the previous value. The end result is that flips/vblank events don't appear to complete as they're stuck waiting for the frame counter to catch up to that massive difference. Fix the problem properly by actually making sure the scanline counter has started to move before we assume that it's safe to enable vblank processing. v2: Less pointless duplication in the code (Chris) Cc: stable(a)vger.kernel.org Cc: Daniel Vetter <daniel.vetter(a)ffwll.ch> Cc: Chris Wilson <chris(a)chris-wilson.co.uk> Reviewed-by: Chris Wilson <chris(a)chris-wilson.co.uk> Fixes: b7792d8b54cc ("drm/i915: Wait for pipe to start before sampling vblank timestamps on gen2") Signed-off-by: Ville Syrjälä <ville.syrjala(a)linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20171129153732.3612-1-ville.s… (cherry picked from commit 8fedd64dabc86d0f31a0d1e152be3aa23c323553) Signed-off-by: Joonas Lahtinen <joonas.lahtinen(a)linux.intel.com> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index 878acc432a4b..e8ccf89cb17b 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -1000,7 +1000,8 @@ enum transcoder intel_pipe_to_cpu_transcoder(struct drm_i915_private *dev_priv, return crtc->config->cpu_transcoder; } -static bool pipe_dsl_stopped(struct drm_i915_private *dev_priv, enum pipe pipe) +static bool pipe_scanline_is_moving(struct drm_i915_private *dev_priv, + enum pipe pipe) { i915_reg_t reg = PIPEDSL(pipe); u32 line1, line2; @@ -1015,7 +1016,28 @@ static bool pipe_dsl_stopped(struct drm_i915_private *dev_priv, enum pipe pipe) msleep(5); line2 = I915_READ(reg) & line_mask; - return line1 == line2; + return line1 != line2; +} + +static void wait_for_pipe_scanline_moving(struct intel_crtc *crtc, bool state) +{ + struct drm_i915_private *dev_priv = to_i915(crtc->base.dev); + enum pipe pipe = crtc->pipe; + + /* Wait for the display line to settle/start moving */ + if (wait_for(pipe_scanline_is_moving(dev_priv, pipe) == state, 100)) + DRM_ERROR("pipe %c scanline %s wait timed out\n", + pipe_name(pipe), onoff(state)); +} + +static void intel_wait_for_pipe_scanline_stopped(struct intel_crtc *crtc) +{ + wait_for_pipe_scanline_moving(crtc, false); +} + +static void intel_wait_for_pipe_scanline_moving(struct intel_crtc *crtc) +{ + wait_for_pipe_scanline_moving(crtc, true); } /* @@ -1038,7 +1060,6 @@ static void intel_wait_for_pipe_off(struct intel_crtc *crtc) { struct drm_i915_private *dev_priv = to_i915(crtc->base.dev); enum transcoder cpu_transcoder = crtc->config->cpu_transcoder; - enum pipe pipe = crtc->pipe; if (INTEL_GEN(dev_priv) >= 4) { i915_reg_t reg = PIPECONF(cpu_transcoder); @@ -1049,9 +1070,7 @@ static void intel_wait_for_pipe_off(struct intel_crtc *crtc) 100)) WARN(1, "pipe_off wait timed out\n"); } else { - /* Wait for the display line to settle */ - if (wait_for(pipe_dsl_stopped(dev_priv, pipe), 100)) - WARN(1, "pipe_off wait timed out\n"); + intel_wait_for_pipe_scanline_stopped(crtc); } } @@ -1936,15 +1955,14 @@ static void intel_enable_pipe(struct intel_crtc *crtc) POSTING_READ(reg); /* - * Until the pipe starts DSL will read as 0, which would cause - * an apparent vblank timestamp jump, which messes up also the - * frame count when it's derived from the timestamps. So let's - * wait for the pipe to start properly before we call - * drm_crtc_vblank_on() + * Until the pipe starts PIPEDSL reads will return a stale value, + * which causes an apparent vblank timestamp jump when PIPEDSL + * resets to its proper value. That also messes up the frame count + * when it's derived from the timestamps. So let's wait for the + * pipe to start properly before we call drm_crtc_vblank_on() */ - if (dev->max_vblank_count == 0 && - wait_for(intel_get_crtc_scanline(crtc) != crtc->scanline_offset, 50)) - DRM_ERROR("pipe %c didn't start\n", pipe_name(pipe)); + if (dev->max_vblank_count == 0) + intel_wait_for_pipe_scanline_moving(crtc); } /** @@ -14643,6 +14661,8 @@ void i830_enable_pipe(struct drm_i915_private *dev_priv, enum pipe pipe) void i830_disable_pipe(struct drm_i915_private *dev_priv, enum pipe pipe) { + struct intel_crtc *crtc = intel_get_crtc_for_pipe(dev_priv, pipe); + DRM_DEBUG_KMS("disabling pipe %c due to force quirk\n", pipe_name(pipe)); @@ -14652,8 +14672,7 @@ void i830_disable_pipe(struct drm_i915_private *dev_priv, enum pipe pipe) I915_WRITE(PIPECONF(pipe), 0); POSTING_READ(PIPECONF(pipe)); - if (wait_for(pipe_dsl_stopped(dev_priv, pipe), 100)) - DRM_ERROR("pipe %c off wait timed out\n", pipe_name(pipe)); + intel_wait_for_pipe_scanline_stopped(crtc); I915_WRITE(DPLL(pipe), DPLL_VGA_MODE_DIS); POSTING_READ(DPLL(pipe));

7 years, 9 months

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[Linux-stable-mirror] FAILED: patch "[PATCH] btrfs: fix missing error return in btrfs_drop_snapshot" failed to apply to 3.18-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 3.18-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From e19182c0fff451e3744c1107d98f072e7ca377a0 Mon Sep 17 00:00:00 2001 From: Jeff Mahoney <jeffm(a)suse.com> Date: Mon, 4 Dec 2017 13:11:45 -0500 Subject: [PATCH] btrfs: fix missing error return in btrfs_drop_snapshot If btrfs_del_root fails in btrfs_drop_snapshot, we'll pick up the error but then return 0 anyway due to mixing err and ret. Fixes: 79787eaab4612 ("btrfs: replace many BUG_ONs with proper error handling") Cc: <stable(a)vger.kernel.org> # v3.4+ Signed-off-by: Jeff Mahoney <jeffm(a)suse.com> Reviewed-by: David Sterba <dsterba(a)suse.com> Signed-off-by: David Sterba <dsterba(a)suse.com> diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 784d41e95ed9..16e46ee3cd16 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -9220,6 +9220,7 @@ int btrfs_drop_snapshot(struct btrfs_root *root, ret = btrfs_del_root(trans, fs_info, &root->root_key); if (ret) { btrfs_abort_transaction(trans, ret); + err = ret; goto out_end_trans; }

7 years, 9 months

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[Linux-stable-mirror] FAILED: patch "[PATCH] btrfs: fix missing error return in btrfs_drop_snapshot" failed to apply to 4.4-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 4.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From e19182c0fff451e3744c1107d98f072e7ca377a0 Mon Sep 17 00:00:00 2001 From: Jeff Mahoney <jeffm(a)suse.com> Date: Mon, 4 Dec 2017 13:11:45 -0500 Subject: [PATCH] btrfs: fix missing error return in btrfs_drop_snapshot If btrfs_del_root fails in btrfs_drop_snapshot, we'll pick up the error but then return 0 anyway due to mixing err and ret. Fixes: 79787eaab4612 ("btrfs: replace many BUG_ONs with proper error handling") Cc: <stable(a)vger.kernel.org> # v3.4+ Signed-off-by: Jeff Mahoney <jeffm(a)suse.com> Reviewed-by: David Sterba <dsterba(a)suse.com> Signed-off-by: David Sterba <dsterba(a)suse.com> diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 784d41e95ed9..16e46ee3cd16 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -9220,6 +9220,7 @@ int btrfs_drop_snapshot(struct btrfs_root *root, ret = btrfs_del_root(trans, fs_info, &root->root_key); if (ret) { btrfs_abort_transaction(trans, ret); + err = ret; goto out_end_trans; }

7 years, 9 months

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[Linux-stable-mirror] FAILED: patch "[PATCH] KVM: x86: fix APIC page invalidation" failed to apply to 4.4-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 4.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From b1394e745b9453dcb5b0671c205b770e87dedb87 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= <rkrcmar(a)redhat.com> Date: Thu, 30 Nov 2017 19:05:45 +0100 Subject: [PATCH] KVM: x86: fix APIC page invalidation MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Implementation of the unpinned APIC page didn't update the VMCS address cache when invalidation was done through range mmu notifiers. This became a problem when the page notifier was removed. Re-introduce the arch-specific helper and call it from ...range_start. Reported-by: Fabian Grünbichler <f.gruenbichler(a)proxmox.com> Fixes: 38b9917350cb ("kvm: vmx: Implement set_apic_access_page_addr") Fixes: 369ea8242c0f ("mm/rmap: update to new mmu_notifier semantic v2") Cc: <stable(a)vger.kernel.org> Reviewed-by: Paolo Bonzini <pbonzini(a)redhat.com> Reviewed-by: Andrea Arcangeli <aarcange(a)redhat.com> Tested-by: Wanpeng Li <wanpeng.li(a)hotmail.com> Tested-by: Fabian Grünbichler <f.gruenbichler(a)proxmox.com> Signed-off-by: Radim Krčmář <rkrcmar(a)redhat.com> diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 62527e053ee4..516798431328 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1448,4 +1448,7 @@ static inline int kvm_cpu_get_apicid(int mps_cpu) #define put_smstate(type, buf, offset, val) \ *(type *)((buf) + (offset) - 0x7e00) = val +void kvm_arch_mmu_notifier_invalidate_range(struct kvm *kvm, + unsigned long start, unsigned long end); + #endif /* _ASM_X86_KVM_HOST_H */ diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 6ca747abfa2f..faf843c9b916 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -6764,6 +6764,20 @@ static void kvm_vcpu_flush_tlb(struct kvm_vcpu *vcpu) kvm_x86_ops->tlb_flush(vcpu); } +void kvm_arch_mmu_notifier_invalidate_range(struct kvm *kvm, + unsigned long start, unsigned long end) +{ + unsigned long apic_address; + + /* + * The physical address of apic access page is stored in the VMCS. + * Update it when it becomes invalid. + */ + apic_address = gfn_to_hva(kvm, APIC_DEFAULT_PHYS_BASE >> PAGE_SHIFT); + if (start <= apic_address && apic_address < end) + kvm_make_all_cpus_request(kvm, KVM_REQ_APIC_PAGE_RELOAD); +} + void kvm_vcpu_reload_apic_access_page(struct kvm_vcpu *vcpu) { struct page *page = NULL; diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index c422c10cd1dd..210bf820385a 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -135,6 +135,11 @@ static void kvm_uevent_notify_change(unsigned int type, struct kvm *kvm); static unsigned long long kvm_createvm_count; static unsigned long long kvm_active_vms; +__weak void kvm_arch_mmu_notifier_invalidate_range(struct kvm *kvm, + unsigned long start, unsigned long end) +{ +} + bool kvm_is_reserved_pfn(kvm_pfn_t pfn) { if (pfn_valid(pfn)) @@ -360,6 +365,9 @@ static void kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn, kvm_flush_remote_tlbs(kvm); spin_unlock(&kvm->mmu_lock); + + kvm_arch_mmu_notifier_invalidate_range(kvm, start, end); + srcu_read_unlock(&kvm->srcu, idx); }

7 years, 9 months

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[Linux-stable-mirror] FAILED: patch "[PATCH] KVM: x86: fix APIC page invalidation" failed to apply to 3.18-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 3.18-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From b1394e745b9453dcb5b0671c205b770e87dedb87 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= <rkrcmar(a)redhat.com> Date: Thu, 30 Nov 2017 19:05:45 +0100 Subject: [PATCH] KVM: x86: fix APIC page invalidation MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Implementation of the unpinned APIC page didn't update the VMCS address cache when invalidation was done through range mmu notifiers. This became a problem when the page notifier was removed. Re-introduce the arch-specific helper and call it from ...range_start. Reported-by: Fabian Grünbichler <f.gruenbichler(a)proxmox.com> Fixes: 38b9917350cb ("kvm: vmx: Implement set_apic_access_page_addr") Fixes: 369ea8242c0f ("mm/rmap: update to new mmu_notifier semantic v2") Cc: <stable(a)vger.kernel.org> Reviewed-by: Paolo Bonzini <pbonzini(a)redhat.com> Reviewed-by: Andrea Arcangeli <aarcange(a)redhat.com> Tested-by: Wanpeng Li <wanpeng.li(a)hotmail.com> Tested-by: Fabian Grünbichler <f.gruenbichler(a)proxmox.com> Signed-off-by: Radim Krčmář <rkrcmar(a)redhat.com> diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 62527e053ee4..516798431328 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1448,4 +1448,7 @@ static inline int kvm_cpu_get_apicid(int mps_cpu) #define put_smstate(type, buf, offset, val) \ *(type *)((buf) + (offset) - 0x7e00) = val +void kvm_arch_mmu_notifier_invalidate_range(struct kvm *kvm, + unsigned long start, unsigned long end); + #endif /* _ASM_X86_KVM_HOST_H */ diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 6ca747abfa2f..faf843c9b916 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -6764,6 +6764,20 @@ static void kvm_vcpu_flush_tlb(struct kvm_vcpu *vcpu) kvm_x86_ops->tlb_flush(vcpu); } +void kvm_arch_mmu_notifier_invalidate_range(struct kvm *kvm, + unsigned long start, unsigned long end) +{ + unsigned long apic_address; + + /* + * The physical address of apic access page is stored in the VMCS. + * Update it when it becomes invalid. + */ + apic_address = gfn_to_hva(kvm, APIC_DEFAULT_PHYS_BASE >> PAGE_SHIFT); + if (start <= apic_address && apic_address < end) + kvm_make_all_cpus_request(kvm, KVM_REQ_APIC_PAGE_RELOAD); +} + void kvm_vcpu_reload_apic_access_page(struct kvm_vcpu *vcpu) { struct page *page = NULL; diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index c422c10cd1dd..210bf820385a 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -135,6 +135,11 @@ static void kvm_uevent_notify_change(unsigned int type, struct kvm *kvm); static unsigned long long kvm_createvm_count; static unsigned long long kvm_active_vms; +__weak void kvm_arch_mmu_notifier_invalidate_range(struct kvm *kvm, + unsigned long start, unsigned long end) +{ +} + bool kvm_is_reserved_pfn(kvm_pfn_t pfn) { if (pfn_valid(pfn)) @@ -360,6 +365,9 @@ static void kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn, kvm_flush_remote_tlbs(kvm); spin_unlock(&kvm->mmu_lock); + + kvm_arch_mmu_notifier_invalidate_range(kvm, start, end); + srcu_read_unlock(&kvm->srcu, idx); }

7 years, 9 months

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[Linux-stable-mirror] FAILED: patch "[PATCH] x86, kvm: move qemu/guest FPU switching out to vcpu_run" failed to apply to 3.18-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 3.18-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From f775b13eedee2f7f3c6fdd4e90fb79090ce5d339 Mon Sep 17 00:00:00 2001 From: Rik van Riel <riel(a)redhat.com> Date: Tue, 14 Nov 2017 16:54:23 -0500 Subject: [PATCH] x86,kvm: move qemu/guest FPU switching out to vcpu_run MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Currently, every time a VCPU is scheduled out, the host kernel will first save the guest FPU/xstate context, then load the qemu userspace FPU context, only to then immediately save the qemu userspace FPU context back to memory. When scheduling in a VCPU, the same extraneous FPU loads and saves are done. This could be avoided by moving from a model where the guest FPU is loaded and stored with preemption disabled, to a model where the qemu userspace FPU is swapped out for the guest FPU context for the duration of the KVM_RUN ioctl. This is done under the VCPU mutex, which is also taken when other tasks inspect the VCPU FPU context, so the code should already be safe for this change. That should come as no surprise, given that s390 already has this optimization. This can fix a bug where KVM calls get_user_pages while owning the FPU, and the file system ends up requesting the FPU again: [258270.527947] __warn+0xcb/0xf0 [258270.527948] warn_slowpath_null+0x1d/0x20 [258270.527951] kernel_fpu_disable+0x3f/0x50 [258270.527953] __kernel_fpu_begin+0x49/0x100 [258270.527955] kernel_fpu_begin+0xe/0x10 [258270.527958] crc32c_pcl_intel_update+0x84/0xb0 [258270.527961] crypto_shash_update+0x3f/0x110 [258270.527968] crc32c+0x63/0x8a [libcrc32c] [258270.527975] dm_bm_checksum+0x1b/0x20 [dm_persistent_data] [258270.527978] node_prepare_for_write+0x44/0x70 [dm_persistent_data] [258270.527985] dm_block_manager_write_callback+0x41/0x50 [dm_persistent_data] [258270.527988] submit_io+0x170/0x1b0 [dm_bufio] [258270.527992] __write_dirty_buffer+0x89/0x90 [dm_bufio] [258270.527994] __make_buffer_clean+0x4f/0x80 [dm_bufio] [258270.527996] __try_evict_buffer+0x42/0x60 [dm_bufio] [258270.527998] dm_bufio_shrink_scan+0xc0/0x130 [dm_bufio] [258270.528002] shrink_slab.part.40+0x1f5/0x420 [258270.528004] shrink_node+0x22c/0x320 [258270.528006] do_try_to_free_pages+0xf5/0x330 [258270.528008] try_to_free_pages+0xe9/0x190 [258270.528009] __alloc_pages_slowpath+0x40f/0xba0 [258270.528011] __alloc_pages_nodemask+0x209/0x260 [258270.528014] alloc_pages_vma+0x1f1/0x250 [258270.528017] do_huge_pmd_anonymous_page+0x123/0x660 [258270.528021] handle_mm_fault+0xfd3/0x1330 [258270.528025] __get_user_pages+0x113/0x640 [258270.528027] get_user_pages+0x4f/0x60 [258270.528063] __gfn_to_pfn_memslot+0x120/0x3f0 [kvm] [258270.528108] try_async_pf+0x66/0x230 [kvm] [258270.528135] tdp_page_fault+0x130/0x280 [kvm] [258270.528149] kvm_mmu_page_fault+0x60/0x120 [kvm] [258270.528158] handle_ept_violation+0x91/0x170 [kvm_intel] [258270.528162] vmx_handle_exit+0x1ca/0x1400 [kvm_intel] No performance changes were detected in quick ping-pong tests on my 4 socket system, which is expected since an FPU+xstate load is on the order of 0.1us, while ping-ponging between CPUs is on the order of 20us, and somewhat noisy. Cc: stable(a)vger.kernel.org Signed-off-by: Rik van Riel <riel(a)redhat.com> Suggested-by: Christian Borntraeger <borntraeger(a)de.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini(a)redhat.com> [Fixed a bug where reset_vcpu called put_fpu without preceding load_fpu, which happened inside from KVM_CREATE_VCPU ioctl. - Radim] Signed-off-by: Radim Krčmář <rkrcmar(a)redhat.com> diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 977de5fb968b..62527e053ee4 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -536,7 +536,20 @@ struct kvm_vcpu_arch { struct kvm_mmu_memory_cache mmu_page_cache; struct kvm_mmu_memory_cache mmu_page_header_cache; + /* + * QEMU userspace and the guest each have their own FPU state. + * In vcpu_run, we switch between the user and guest FPU contexts. + * While running a VCPU, the VCPU thread will have the guest FPU + * context. + * + * Note that while the PKRU state lives inside the fpu registers, + * it is switched out separately at VMENTER and VMEXIT time. The + * "guest_fpu" state here contains the guest FPU context, with the + * host PRKU bits. + */ + struct fpu user_fpu; struct fpu guest_fpu; + u64 xcr0; u64 guest_supported_xcr0; u32 guest_xstate_size; diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index eee8e7faf1af..c8da1680a7d6 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -2937,7 +2937,6 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) srcu_read_unlock(&vcpu->kvm->srcu, idx); pagefault_enable(); kvm_x86_ops->vcpu_put(vcpu); - kvm_put_guest_fpu(vcpu); vcpu->arch.last_host_tsc = rdtsc(); } @@ -5254,13 +5253,10 @@ static void emulator_halt(struct x86_emulate_ctxt *ctxt) static void emulator_get_fpu(struct x86_emulate_ctxt *ctxt) { - preempt_disable(); - kvm_load_guest_fpu(emul_to_vcpu(ctxt)); } static void emulator_put_fpu(struct x86_emulate_ctxt *ctxt) { - preempt_enable(); } static int emulator_intercept(struct x86_emulate_ctxt *ctxt, @@ -6952,7 +6948,6 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu) preempt_disable(); kvm_x86_ops->prepare_guest_switch(vcpu); - kvm_load_guest_fpu(vcpu); /* * Disable IRQs before setting IN_GUEST_MODE. Posted interrupt @@ -7297,12 +7292,14 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run) } } + kvm_load_guest_fpu(vcpu); + if (unlikely(vcpu->arch.complete_userspace_io)) { int (*cui)(struct kvm_vcpu *) = vcpu->arch.complete_userspace_io; vcpu->arch.complete_userspace_io = NULL; r = cui(vcpu); if (r <= 0) - goto out; + goto out_fpu; } else WARN_ON(vcpu->arch.pio.count || vcpu->mmio_needed); @@ -7311,6 +7308,8 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run) else r = vcpu_run(vcpu); +out_fpu: + kvm_put_guest_fpu(vcpu); out: post_kvm_run_save(vcpu); kvm_sigset_deactivate(vcpu); @@ -7704,32 +7703,25 @@ static void fx_init(struct kvm_vcpu *vcpu) vcpu->arch.cr0 |= X86_CR0_ET; } +/* Swap (qemu) user FPU context for the guest FPU context. */ void kvm_load_guest_fpu(struct kvm_vcpu *vcpu) { - if (vcpu->guest_fpu_loaded) - return; - - /* - * Restore all possible states in the guest, - * and assume host would use all available bits. - * Guest xcr0 would be loaded later. - */ - vcpu->guest_fpu_loaded = 1; - __kernel_fpu_begin(); + preempt_disable(); + copy_fpregs_to_fpstate(&vcpu->arch.user_fpu); /* PKRU is separately restored in kvm_x86_ops->run. */ __copy_kernel_to_fpregs(&vcpu->arch.guest_fpu.state, ~XFEATURE_MASK_PKRU); + preempt_enable(); trace_kvm_fpu(1); } +/* When vcpu_run ends, restore user space FPU context. */ void kvm_put_guest_fpu(struct kvm_vcpu *vcpu) { - if (!vcpu->guest_fpu_loaded) - return; - - vcpu->guest_fpu_loaded = 0; + preempt_disable(); copy_fpregs_to_fpstate(&vcpu->arch.guest_fpu); - __kernel_fpu_end(); + copy_kernel_to_fpregs(&vcpu->arch.user_fpu.state); + preempt_enable(); ++vcpu->stat.fpu_reload; trace_kvm_fpu(0); } @@ -7846,7 +7838,8 @@ void kvm_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event) * To avoid have the INIT path from kvm_apic_has_events() that be * called with loaded FPU and does not let userspace fix the state. */ - kvm_put_guest_fpu(vcpu); + if (init_event) + kvm_put_guest_fpu(vcpu); mpx_state_buffer = get_xsave_addr(&vcpu->arch.guest_fpu.state.xsave, XFEATURE_MASK_BNDREGS); if (mpx_state_buffer) @@ -7855,6 +7848,8 @@ void kvm_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event) XFEATURE_MASK_BNDCSR); if (mpx_state_buffer) memset(mpx_state_buffer, 0, sizeof(struct mpx_bndcsr)); + if (init_event) + kvm_load_guest_fpu(vcpu); } if (!init_event) { diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 893d6d606cd0..6bdd4b9f6611 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -232,7 +232,7 @@ struct kvm_vcpu { struct mutex mutex; struct kvm_run *run; - int guest_fpu_loaded, guest_xcr0_loaded; + int guest_xcr0_loaded; struct swait_queue_head wq; struct pid __rcu *pid; int sigset_active;

7 years, 9 months

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[Linux-stable-mirror] FAILED: patch "[PATCH] x86, kvm: move qemu/guest FPU switching out to vcpu_run" failed to apply to 4.9-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 4.9-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From f775b13eedee2f7f3c6fdd4e90fb79090ce5d339 Mon Sep 17 00:00:00 2001 From: Rik van Riel <riel(a)redhat.com> Date: Tue, 14 Nov 2017 16:54:23 -0500 Subject: [PATCH] x86,kvm: move qemu/guest FPU switching out to vcpu_run MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Currently, every time a VCPU is scheduled out, the host kernel will first save the guest FPU/xstate context, then load the qemu userspace FPU context, only to then immediately save the qemu userspace FPU context back to memory. When scheduling in a VCPU, the same extraneous FPU loads and saves are done. This could be avoided by moving from a model where the guest FPU is loaded and stored with preemption disabled, to a model where the qemu userspace FPU is swapped out for the guest FPU context for the duration of the KVM_RUN ioctl. This is done under the VCPU mutex, which is also taken when other tasks inspect the VCPU FPU context, so the code should already be safe for this change. That should come as no surprise, given that s390 already has this optimization. This can fix a bug where KVM calls get_user_pages while owning the FPU, and the file system ends up requesting the FPU again: [258270.527947] __warn+0xcb/0xf0 [258270.527948] warn_slowpath_null+0x1d/0x20 [258270.527951] kernel_fpu_disable+0x3f/0x50 [258270.527953] __kernel_fpu_begin+0x49/0x100 [258270.527955] kernel_fpu_begin+0xe/0x10 [258270.527958] crc32c_pcl_intel_update+0x84/0xb0 [258270.527961] crypto_shash_update+0x3f/0x110 [258270.527968] crc32c+0x63/0x8a [libcrc32c] [258270.527975] dm_bm_checksum+0x1b/0x20 [dm_persistent_data] [258270.527978] node_prepare_for_write+0x44/0x70 [dm_persistent_data] [258270.527985] dm_block_manager_write_callback+0x41/0x50 [dm_persistent_data] [258270.527988] submit_io+0x170/0x1b0 [dm_bufio] [258270.527992] __write_dirty_buffer+0x89/0x90 [dm_bufio] [258270.527994] __make_buffer_clean+0x4f/0x80 [dm_bufio] [258270.527996] __try_evict_buffer+0x42/0x60 [dm_bufio] [258270.527998] dm_bufio_shrink_scan+0xc0/0x130 [dm_bufio] [258270.528002] shrink_slab.part.40+0x1f5/0x420 [258270.528004] shrink_node+0x22c/0x320 [258270.528006] do_try_to_free_pages+0xf5/0x330 [258270.528008] try_to_free_pages+0xe9/0x190 [258270.528009] __alloc_pages_slowpath+0x40f/0xba0 [258270.528011] __alloc_pages_nodemask+0x209/0x260 [258270.528014] alloc_pages_vma+0x1f1/0x250 [258270.528017] do_huge_pmd_anonymous_page+0x123/0x660 [258270.528021] handle_mm_fault+0xfd3/0x1330 [258270.528025] __get_user_pages+0x113/0x640 [258270.528027] get_user_pages+0x4f/0x60 [258270.528063] __gfn_to_pfn_memslot+0x120/0x3f0 [kvm] [258270.528108] try_async_pf+0x66/0x230 [kvm] [258270.528135] tdp_page_fault+0x130/0x280 [kvm] [258270.528149] kvm_mmu_page_fault+0x60/0x120 [kvm] [258270.528158] handle_ept_violation+0x91/0x170 [kvm_intel] [258270.528162] vmx_handle_exit+0x1ca/0x1400 [kvm_intel] No performance changes were detected in quick ping-pong tests on my 4 socket system, which is expected since an FPU+xstate load is on the order of 0.1us, while ping-ponging between CPUs is on the order of 20us, and somewhat noisy. Cc: stable(a)vger.kernel.org Signed-off-by: Rik van Riel <riel(a)redhat.com> Suggested-by: Christian Borntraeger <borntraeger(a)de.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini(a)redhat.com> [Fixed a bug where reset_vcpu called put_fpu without preceding load_fpu, which happened inside from KVM_CREATE_VCPU ioctl. - Radim] Signed-off-by: Radim Krčmář <rkrcmar(a)redhat.com> diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 977de5fb968b..62527e053ee4 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -536,7 +536,20 @@ struct kvm_vcpu_arch { struct kvm_mmu_memory_cache mmu_page_cache; struct kvm_mmu_memory_cache mmu_page_header_cache; + /* + * QEMU userspace and the guest each have their own FPU state. + * In vcpu_run, we switch between the user and guest FPU contexts. + * While running a VCPU, the VCPU thread will have the guest FPU + * context. + * + * Note that while the PKRU state lives inside the fpu registers, + * it is switched out separately at VMENTER and VMEXIT time. The + * "guest_fpu" state here contains the guest FPU context, with the + * host PRKU bits. + */ + struct fpu user_fpu; struct fpu guest_fpu; + u64 xcr0; u64 guest_supported_xcr0; u32 guest_xstate_size; diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index eee8e7faf1af..c8da1680a7d6 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -2937,7 +2937,6 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) srcu_read_unlock(&vcpu->kvm->srcu, idx); pagefault_enable(); kvm_x86_ops->vcpu_put(vcpu); - kvm_put_guest_fpu(vcpu); vcpu->arch.last_host_tsc = rdtsc(); } @@ -5254,13 +5253,10 @@ static void emulator_halt(struct x86_emulate_ctxt *ctxt) static void emulator_get_fpu(struct x86_emulate_ctxt *ctxt) { - preempt_disable(); - kvm_load_guest_fpu(emul_to_vcpu(ctxt)); } static void emulator_put_fpu(struct x86_emulate_ctxt *ctxt) { - preempt_enable(); } static int emulator_intercept(struct x86_emulate_ctxt *ctxt, @@ -6952,7 +6948,6 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu) preempt_disable(); kvm_x86_ops->prepare_guest_switch(vcpu); - kvm_load_guest_fpu(vcpu); /* * Disable IRQs before setting IN_GUEST_MODE. Posted interrupt @@ -7297,12 +7292,14 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run) } } + kvm_load_guest_fpu(vcpu); + if (unlikely(vcpu->arch.complete_userspace_io)) { int (*cui)(struct kvm_vcpu *) = vcpu->arch.complete_userspace_io; vcpu->arch.complete_userspace_io = NULL; r = cui(vcpu); if (r <= 0) - goto out; + goto out_fpu; } else WARN_ON(vcpu->arch.pio.count || vcpu->mmio_needed); @@ -7311,6 +7308,8 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run) else r = vcpu_run(vcpu); +out_fpu: + kvm_put_guest_fpu(vcpu); out: post_kvm_run_save(vcpu); kvm_sigset_deactivate(vcpu); @@ -7704,32 +7703,25 @@ static void fx_init(struct kvm_vcpu *vcpu) vcpu->arch.cr0 |= X86_CR0_ET; } +/* Swap (qemu) user FPU context for the guest FPU context. */ void kvm_load_guest_fpu(struct kvm_vcpu *vcpu) { - if (vcpu->guest_fpu_loaded) - return; - - /* - * Restore all possible states in the guest, - * and assume host would use all available bits. - * Guest xcr0 would be loaded later. - */ - vcpu->guest_fpu_loaded = 1; - __kernel_fpu_begin(); + preempt_disable(); + copy_fpregs_to_fpstate(&vcpu->arch.user_fpu); /* PKRU is separately restored in kvm_x86_ops->run. */ __copy_kernel_to_fpregs(&vcpu->arch.guest_fpu.state, ~XFEATURE_MASK_PKRU); + preempt_enable(); trace_kvm_fpu(1); } +/* When vcpu_run ends, restore user space FPU context. */ void kvm_put_guest_fpu(struct kvm_vcpu *vcpu) { - if (!vcpu->guest_fpu_loaded) - return; - - vcpu->guest_fpu_loaded = 0; + preempt_disable(); copy_fpregs_to_fpstate(&vcpu->arch.guest_fpu); - __kernel_fpu_end(); + copy_kernel_to_fpregs(&vcpu->arch.user_fpu.state); + preempt_enable(); ++vcpu->stat.fpu_reload; trace_kvm_fpu(0); } @@ -7846,7 +7838,8 @@ void kvm_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event) * To avoid have the INIT path from kvm_apic_has_events() that be * called with loaded FPU and does not let userspace fix the state. */ - kvm_put_guest_fpu(vcpu); + if (init_event) + kvm_put_guest_fpu(vcpu); mpx_state_buffer = get_xsave_addr(&vcpu->arch.guest_fpu.state.xsave, XFEATURE_MASK_BNDREGS); if (mpx_state_buffer) @@ -7855,6 +7848,8 @@ void kvm_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event) XFEATURE_MASK_BNDCSR); if (mpx_state_buffer) memset(mpx_state_buffer, 0, sizeof(struct mpx_bndcsr)); + if (init_event) + kvm_load_guest_fpu(vcpu); } if (!init_event) { diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 893d6d606cd0..6bdd4b9f6611 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -232,7 +232,7 @@ struct kvm_vcpu { struct mutex mutex; struct kvm_run *run; - int guest_fpu_loaded, guest_xcr0_loaded; + int guest_xcr0_loaded; struct swait_queue_head wq; struct pid __rcu *pid; int sigset_active;

7 years, 9 months

1
0
0 0

[Linux-stable-mirror] FAILED: patch "[PATCH] x86, kvm: move qemu/guest FPU switching out to vcpu_run" failed to apply to 4.4-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 4.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From f775b13eedee2f7f3c6fdd4e90fb79090ce5d339 Mon Sep 17 00:00:00 2001 From: Rik van Riel <riel(a)redhat.com> Date: Tue, 14 Nov 2017 16:54:23 -0500 Subject: [PATCH] x86,kvm: move qemu/guest FPU switching out to vcpu_run MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Currently, every time a VCPU is scheduled out, the host kernel will first save the guest FPU/xstate context, then load the qemu userspace FPU context, only to then immediately save the qemu userspace FPU context back to memory. When scheduling in a VCPU, the same extraneous FPU loads and saves are done. This could be avoided by moving from a model where the guest FPU is loaded and stored with preemption disabled, to a model where the qemu userspace FPU is swapped out for the guest FPU context for the duration of the KVM_RUN ioctl. This is done under the VCPU mutex, which is also taken when other tasks inspect the VCPU FPU context, so the code should already be safe for this change. That should come as no surprise, given that s390 already has this optimization. This can fix a bug where KVM calls get_user_pages while owning the FPU, and the file system ends up requesting the FPU again: [258270.527947] __warn+0xcb/0xf0 [258270.527948] warn_slowpath_null+0x1d/0x20 [258270.527951] kernel_fpu_disable+0x3f/0x50 [258270.527953] __kernel_fpu_begin+0x49/0x100 [258270.527955] kernel_fpu_begin+0xe/0x10 [258270.527958] crc32c_pcl_intel_update+0x84/0xb0 [258270.527961] crypto_shash_update+0x3f/0x110 [258270.527968] crc32c+0x63/0x8a [libcrc32c] [258270.527975] dm_bm_checksum+0x1b/0x20 [dm_persistent_data] [258270.527978] node_prepare_for_write+0x44/0x70 [dm_persistent_data] [258270.527985] dm_block_manager_write_callback+0x41/0x50 [dm_persistent_data] [258270.527988] submit_io+0x170/0x1b0 [dm_bufio] [258270.527992] __write_dirty_buffer+0x89/0x90 [dm_bufio] [258270.527994] __make_buffer_clean+0x4f/0x80 [dm_bufio] [258270.527996] __try_evict_buffer+0x42/0x60 [dm_bufio] [258270.527998] dm_bufio_shrink_scan+0xc0/0x130 [dm_bufio] [258270.528002] shrink_slab.part.40+0x1f5/0x420 [258270.528004] shrink_node+0x22c/0x320 [258270.528006] do_try_to_free_pages+0xf5/0x330 [258270.528008] try_to_free_pages+0xe9/0x190 [258270.528009] __alloc_pages_slowpath+0x40f/0xba0 [258270.528011] __alloc_pages_nodemask+0x209/0x260 [258270.528014] alloc_pages_vma+0x1f1/0x250 [258270.528017] do_huge_pmd_anonymous_page+0x123/0x660 [258270.528021] handle_mm_fault+0xfd3/0x1330 [258270.528025] __get_user_pages+0x113/0x640 [258270.528027] get_user_pages+0x4f/0x60 [258270.528063] __gfn_to_pfn_memslot+0x120/0x3f0 [kvm] [258270.528108] try_async_pf+0x66/0x230 [kvm] [258270.528135] tdp_page_fault+0x130/0x280 [kvm] [258270.528149] kvm_mmu_page_fault+0x60/0x120 [kvm] [258270.528158] handle_ept_violation+0x91/0x170 [kvm_intel] [258270.528162] vmx_handle_exit+0x1ca/0x1400 [kvm_intel] No performance changes were detected in quick ping-pong tests on my 4 socket system, which is expected since an FPU+xstate load is on the order of 0.1us, while ping-ponging between CPUs is on the order of 20us, and somewhat noisy. Cc: stable(a)vger.kernel.org Signed-off-by: Rik van Riel <riel(a)redhat.com> Suggested-by: Christian Borntraeger <borntraeger(a)de.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini(a)redhat.com> [Fixed a bug where reset_vcpu called put_fpu without preceding load_fpu, which happened inside from KVM_CREATE_VCPU ioctl. - Radim] Signed-off-by: Radim Krčmář <rkrcmar(a)redhat.com> diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 977de5fb968b..62527e053ee4 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -536,7 +536,20 @@ struct kvm_vcpu_arch { struct kvm_mmu_memory_cache mmu_page_cache; struct kvm_mmu_memory_cache mmu_page_header_cache; + /* + * QEMU userspace and the guest each have their own FPU state. + * In vcpu_run, we switch between the user and guest FPU contexts. + * While running a VCPU, the VCPU thread will have the guest FPU + * context. + * + * Note that while the PKRU state lives inside the fpu registers, + * it is switched out separately at VMENTER and VMEXIT time. The + * "guest_fpu" state here contains the guest FPU context, with the + * host PRKU bits. + */ + struct fpu user_fpu; struct fpu guest_fpu; + u64 xcr0; u64 guest_supported_xcr0; u32 guest_xstate_size; diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index eee8e7faf1af..c8da1680a7d6 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -2937,7 +2937,6 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) srcu_read_unlock(&vcpu->kvm->srcu, idx); pagefault_enable(); kvm_x86_ops->vcpu_put(vcpu); - kvm_put_guest_fpu(vcpu); vcpu->arch.last_host_tsc = rdtsc(); } @@ -5254,13 +5253,10 @@ static void emulator_halt(struct x86_emulate_ctxt *ctxt) static void emulator_get_fpu(struct x86_emulate_ctxt *ctxt) { - preempt_disable(); - kvm_load_guest_fpu(emul_to_vcpu(ctxt)); } static void emulator_put_fpu(struct x86_emulate_ctxt *ctxt) { - preempt_enable(); } static int emulator_intercept(struct x86_emulate_ctxt *ctxt, @@ -6952,7 +6948,6 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu) preempt_disable(); kvm_x86_ops->prepare_guest_switch(vcpu); - kvm_load_guest_fpu(vcpu); /* * Disable IRQs before setting IN_GUEST_MODE. Posted interrupt @@ -7297,12 +7292,14 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run) } } + kvm_load_guest_fpu(vcpu); + if (unlikely(vcpu->arch.complete_userspace_io)) { int (*cui)(struct kvm_vcpu *) = vcpu->arch.complete_userspace_io; vcpu->arch.complete_userspace_io = NULL; r = cui(vcpu); if (r <= 0) - goto out; + goto out_fpu; } else WARN_ON(vcpu->arch.pio.count || vcpu->mmio_needed); @@ -7311,6 +7308,8 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run) else r = vcpu_run(vcpu); +out_fpu: + kvm_put_guest_fpu(vcpu); out: post_kvm_run_save(vcpu); kvm_sigset_deactivate(vcpu); @@ -7704,32 +7703,25 @@ static void fx_init(struct kvm_vcpu *vcpu) vcpu->arch.cr0 |= X86_CR0_ET; } +/* Swap (qemu) user FPU context for the guest FPU context. */ void kvm_load_guest_fpu(struct kvm_vcpu *vcpu) { - if (vcpu->guest_fpu_loaded) - return; - - /* - * Restore all possible states in the guest, - * and assume host would use all available bits. - * Guest xcr0 would be loaded later. - */ - vcpu->guest_fpu_loaded = 1; - __kernel_fpu_begin(); + preempt_disable(); + copy_fpregs_to_fpstate(&vcpu->arch.user_fpu); /* PKRU is separately restored in kvm_x86_ops->run. */ __copy_kernel_to_fpregs(&vcpu->arch.guest_fpu.state, ~XFEATURE_MASK_PKRU); + preempt_enable(); trace_kvm_fpu(1); } +/* When vcpu_run ends, restore user space FPU context. */ void kvm_put_guest_fpu(struct kvm_vcpu *vcpu) { - if (!vcpu->guest_fpu_loaded) - return; - - vcpu->guest_fpu_loaded = 0; + preempt_disable(); copy_fpregs_to_fpstate(&vcpu->arch.guest_fpu); - __kernel_fpu_end(); + copy_kernel_to_fpregs(&vcpu->arch.user_fpu.state); + preempt_enable(); ++vcpu->stat.fpu_reload; trace_kvm_fpu(0); } @@ -7846,7 +7838,8 @@ void kvm_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event) * To avoid have the INIT path from kvm_apic_has_events() that be * called with loaded FPU and does not let userspace fix the state. */ - kvm_put_guest_fpu(vcpu); + if (init_event) + kvm_put_guest_fpu(vcpu); mpx_state_buffer = get_xsave_addr(&vcpu->arch.guest_fpu.state.xsave, XFEATURE_MASK_BNDREGS); if (mpx_state_buffer) @@ -7855,6 +7848,8 @@ void kvm_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event) XFEATURE_MASK_BNDCSR); if (mpx_state_buffer) memset(mpx_state_buffer, 0, sizeof(struct mpx_bndcsr)); + if (init_event) + kvm_load_guest_fpu(vcpu); } if (!init_event) { diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 893d6d606cd0..6bdd4b9f6611 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -232,7 +232,7 @@ struct kvm_vcpu { struct mutex mutex; struct kvm_run *run; - int guest_fpu_loaded, guest_xcr0_loaded; + int guest_xcr0_loaded; struct swait_queue_head wq; struct pid __rcu *pid; int sigset_active;

7 years, 9 months

1
0
0 0

[Linux-stable-mirror] FAILED: patch "[PATCH] x86, kvm: move qemu/guest FPU switching out to vcpu_run" failed to apply to 4.14-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 4.14-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From f775b13eedee2f7f3c6fdd4e90fb79090ce5d339 Mon Sep 17 00:00:00 2001 From: Rik van Riel <riel(a)redhat.com> Date: Tue, 14 Nov 2017 16:54:23 -0500 Subject: [PATCH] x86,kvm: move qemu/guest FPU switching out to vcpu_run MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Currently, every time a VCPU is scheduled out, the host kernel will first save the guest FPU/xstate context, then load the qemu userspace FPU context, only to then immediately save the qemu userspace FPU context back to memory. When scheduling in a VCPU, the same extraneous FPU loads and saves are done. This could be avoided by moving from a model where the guest FPU is loaded and stored with preemption disabled, to a model where the qemu userspace FPU is swapped out for the guest FPU context for the duration of the KVM_RUN ioctl. This is done under the VCPU mutex, which is also taken when other tasks inspect the VCPU FPU context, so the code should already be safe for this change. That should come as no surprise, given that s390 already has this optimization. This can fix a bug where KVM calls get_user_pages while owning the FPU, and the file system ends up requesting the FPU again: [258270.527947] __warn+0xcb/0xf0 [258270.527948] warn_slowpath_null+0x1d/0x20 [258270.527951] kernel_fpu_disable+0x3f/0x50 [258270.527953] __kernel_fpu_begin+0x49/0x100 [258270.527955] kernel_fpu_begin+0xe/0x10 [258270.527958] crc32c_pcl_intel_update+0x84/0xb0 [258270.527961] crypto_shash_update+0x3f/0x110 [258270.527968] crc32c+0x63/0x8a [libcrc32c] [258270.527975] dm_bm_checksum+0x1b/0x20 [dm_persistent_data] [258270.527978] node_prepare_for_write+0x44/0x70 [dm_persistent_data] [258270.527985] dm_block_manager_write_callback+0x41/0x50 [dm_persistent_data] [258270.527988] submit_io+0x170/0x1b0 [dm_bufio] [258270.527992] __write_dirty_buffer+0x89/0x90 [dm_bufio] [258270.527994] __make_buffer_clean+0x4f/0x80 [dm_bufio] [258270.527996] __try_evict_buffer+0x42/0x60 [dm_bufio] [258270.527998] dm_bufio_shrink_scan+0xc0/0x130 [dm_bufio] [258270.528002] shrink_slab.part.40+0x1f5/0x420 [258270.528004] shrink_node+0x22c/0x320 [258270.528006] do_try_to_free_pages+0xf5/0x330 [258270.528008] try_to_free_pages+0xe9/0x190 [258270.528009] __alloc_pages_slowpath+0x40f/0xba0 [258270.528011] __alloc_pages_nodemask+0x209/0x260 [258270.528014] alloc_pages_vma+0x1f1/0x250 [258270.528017] do_huge_pmd_anonymous_page+0x123/0x660 [258270.528021] handle_mm_fault+0xfd3/0x1330 [258270.528025] __get_user_pages+0x113/0x640 [258270.528027] get_user_pages+0x4f/0x60 [258270.528063] __gfn_to_pfn_memslot+0x120/0x3f0 [kvm] [258270.528108] try_async_pf+0x66/0x230 [kvm] [258270.528135] tdp_page_fault+0x130/0x280 [kvm] [258270.528149] kvm_mmu_page_fault+0x60/0x120 [kvm] [258270.528158] handle_ept_violation+0x91/0x170 [kvm_intel] [258270.528162] vmx_handle_exit+0x1ca/0x1400 [kvm_intel] No performance changes were detected in quick ping-pong tests on my 4 socket system, which is expected since an FPU+xstate load is on the order of 0.1us, while ping-ponging between CPUs is on the order of 20us, and somewhat noisy. Cc: stable(a)vger.kernel.org Signed-off-by: Rik van Riel <riel(a)redhat.com> Suggested-by: Christian Borntraeger <borntraeger(a)de.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini(a)redhat.com> [Fixed a bug where reset_vcpu called put_fpu without preceding load_fpu, which happened inside from KVM_CREATE_VCPU ioctl. - Radim] Signed-off-by: Radim Krčmář <rkrcmar(a)redhat.com> diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 977de5fb968b..62527e053ee4 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -536,7 +536,20 @@ struct kvm_vcpu_arch { struct kvm_mmu_memory_cache mmu_page_cache; struct kvm_mmu_memory_cache mmu_page_header_cache; + /* + * QEMU userspace and the guest each have their own FPU state. + * In vcpu_run, we switch between the user and guest FPU contexts. + * While running a VCPU, the VCPU thread will have the guest FPU + * context. + * + * Note that while the PKRU state lives inside the fpu registers, + * it is switched out separately at VMENTER and VMEXIT time. The + * "guest_fpu" state here contains the guest FPU context, with the + * host PRKU bits. + */ + struct fpu user_fpu; struct fpu guest_fpu; + u64 xcr0; u64 guest_supported_xcr0; u32 guest_xstate_size; diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index eee8e7faf1af..c8da1680a7d6 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -2937,7 +2937,6 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) srcu_read_unlock(&vcpu->kvm->srcu, idx); pagefault_enable(); kvm_x86_ops->vcpu_put(vcpu); - kvm_put_guest_fpu(vcpu); vcpu->arch.last_host_tsc = rdtsc(); } @@ -5254,13 +5253,10 @@ static void emulator_halt(struct x86_emulate_ctxt *ctxt) static void emulator_get_fpu(struct x86_emulate_ctxt *ctxt) { - preempt_disable(); - kvm_load_guest_fpu(emul_to_vcpu(ctxt)); } static void emulator_put_fpu(struct x86_emulate_ctxt *ctxt) { - preempt_enable(); } static int emulator_intercept(struct x86_emulate_ctxt *ctxt, @@ -6952,7 +6948,6 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu) preempt_disable(); kvm_x86_ops->prepare_guest_switch(vcpu); - kvm_load_guest_fpu(vcpu); /* * Disable IRQs before setting IN_GUEST_MODE. Posted interrupt @@ -7297,12 +7292,14 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run) } } + kvm_load_guest_fpu(vcpu); + if (unlikely(vcpu->arch.complete_userspace_io)) { int (*cui)(struct kvm_vcpu *) = vcpu->arch.complete_userspace_io; vcpu->arch.complete_userspace_io = NULL; r = cui(vcpu); if (r <= 0) - goto out; + goto out_fpu; } else WARN_ON(vcpu->arch.pio.count || vcpu->mmio_needed); @@ -7311,6 +7308,8 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run) else r = vcpu_run(vcpu); +out_fpu: + kvm_put_guest_fpu(vcpu); out: post_kvm_run_save(vcpu); kvm_sigset_deactivate(vcpu); @@ -7704,32 +7703,25 @@ static void fx_init(struct kvm_vcpu *vcpu) vcpu->arch.cr0 |= X86_CR0_ET; } +/* Swap (qemu) user FPU context for the guest FPU context. */ void kvm_load_guest_fpu(struct kvm_vcpu *vcpu) { - if (vcpu->guest_fpu_loaded) - return; - - /* - * Restore all possible states in the guest, - * and assume host would use all available bits. - * Guest xcr0 would be loaded later. - */ - vcpu->guest_fpu_loaded = 1; - __kernel_fpu_begin(); + preempt_disable(); + copy_fpregs_to_fpstate(&vcpu->arch.user_fpu); /* PKRU is separately restored in kvm_x86_ops->run. */ __copy_kernel_to_fpregs(&vcpu->arch.guest_fpu.state, ~XFEATURE_MASK_PKRU); + preempt_enable(); trace_kvm_fpu(1); } +/* When vcpu_run ends, restore user space FPU context. */ void kvm_put_guest_fpu(struct kvm_vcpu *vcpu) { - if (!vcpu->guest_fpu_loaded) - return; - - vcpu->guest_fpu_loaded = 0; + preempt_disable(); copy_fpregs_to_fpstate(&vcpu->arch.guest_fpu); - __kernel_fpu_end(); + copy_kernel_to_fpregs(&vcpu->arch.user_fpu.state); + preempt_enable(); ++vcpu->stat.fpu_reload; trace_kvm_fpu(0); } @@ -7846,7 +7838,8 @@ void kvm_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event) * To avoid have the INIT path from kvm_apic_has_events() that be * called with loaded FPU and does not let userspace fix the state. */ - kvm_put_guest_fpu(vcpu); + if (init_event) + kvm_put_guest_fpu(vcpu); mpx_state_buffer = get_xsave_addr(&vcpu->arch.guest_fpu.state.xsave, XFEATURE_MASK_BNDREGS); if (mpx_state_buffer) @@ -7855,6 +7848,8 @@ void kvm_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event) XFEATURE_MASK_BNDCSR); if (mpx_state_buffer) memset(mpx_state_buffer, 0, sizeof(struct mpx_bndcsr)); + if (init_event) + kvm_load_guest_fpu(vcpu); } if (!init_event) { diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 893d6d606cd0..6bdd4b9f6611 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -232,7 +232,7 @@ struct kvm_vcpu { struct mutex mutex; struct kvm_run *run; - int guest_fpu_loaded, guest_xcr0_loaded; + int guest_xcr0_loaded; struct swait_queue_head wq; struct pid __rcu *pid; int sigset_active;

7 years, 9 months

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[Linux-stable-mirror] FAILED: patch "[PATCH] KEYS: add missing permission check for request_key()" failed to apply to 4.4-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 4.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 4dca6ea1d9432052afb06baf2e3ae78188a4410b Mon Sep 17 00:00:00 2001 From: Eric Biggers <ebiggers(a)google.com> Date: Fri, 8 Dec 2017 15:13:27 +0000 Subject: [PATCH] KEYS: add missing permission check for request_key() destination When the request_key() syscall is not passed a destination keyring, it links the requested key (if constructed) into the "default" request-key keyring. This should require Write permission to the keyring. However, there is actually no permission check. This can be abused to add keys to any keyring to which only Search permission is granted. This is because Search permission allows joining the keyring. keyctl_set_reqkey_keyring(KEY_REQKEY_DEFL_SESSION_KEYRING) then will set the default request-key keyring to the session keyring. Then, request_key() can be used to add keys to the keyring. Both negatively and positively instantiated keys can be added using this method. Adding negative keys is trivial. Adding a positive key is a bit trickier. It requires that either /sbin/request-key positively instantiates the key, or that another thread adds the key to the process keyring at just the right time, such that request_key() misses it initially but then finds it in construct_alloc_key(). Fix this bug by checking for Write permission to the keyring in construct_get_dest_keyring() when the default keyring is being used. We don't do the permission check for non-default keyrings because that was already done by the earlier call to lookup_user_key(). Also, request_key_and_link() is currently passed a 'struct key *' rather than a key_ref_t, so the "possessed" bit is unavailable. We also don't do the permission check for the "requestor keyring", to continue to support the use case described by commit 8bbf4976b59f ("KEYS: Alter use of key instantiation link-to-keyring argument") where /sbin/request-key recursively calls request_key() to add keys to the original requestor's destination keyring. (I don't know of any users who actually do that, though...) Fixes: 3e30148c3d52 ("[PATCH] Keys: Make request-key create an authorisation key") Cc: <stable(a)vger.kernel.org> # v2.6.13+ Signed-off-by: Eric Biggers <ebiggers(a)google.com> Signed-off-by: David Howells <dhowells(a)redhat.com> diff --git a/security/keys/request_key.c b/security/keys/request_key.c index c6880af8b411..114f7408feee 100644 --- a/security/keys/request_key.c +++ b/security/keys/request_key.c @@ -251,11 +251,12 @@ static int construct_key(struct key *key, const void *callout_info, * The keyring selected is returned with an extra reference upon it which the * caller must release. */ -static void construct_get_dest_keyring(struct key **_dest_keyring) +static int construct_get_dest_keyring(struct key **_dest_keyring) { struct request_key_auth *rka; const struct cred *cred = current_cred(); struct key *dest_keyring = *_dest_keyring, *authkey; + int ret; kenter("%p", dest_keyring); @@ -264,6 +265,8 @@ static void construct_get_dest_keyring(struct key **_dest_keyring) /* the caller supplied one */ key_get(dest_keyring); } else { + bool do_perm_check = true; + /* use a default keyring; falling through the cases until we * find one that we actually have */ switch (cred->jit_keyring) { @@ -278,8 +281,10 @@ static void construct_get_dest_keyring(struct key **_dest_keyring) dest_keyring = key_get(rka->dest_keyring); up_read(&authkey->sem); - if (dest_keyring) + if (dest_keyring) { + do_perm_check = false; break; + } } case KEY_REQKEY_DEFL_THREAD_KEYRING: @@ -314,11 +319,29 @@ static void construct_get_dest_keyring(struct key **_dest_keyring) default: BUG(); } + + /* + * Require Write permission on the keyring. This is essential + * because the default keyring may be the session keyring, and + * joining a keyring only requires Search permission. + * + * However, this check is skipped for the "requestor keyring" so + * that /sbin/request-key can itself use request_key() to add + * keys to the original requestor's destination keyring. + */ + if (dest_keyring && do_perm_check) { + ret = key_permission(make_key_ref(dest_keyring, 1), + KEY_NEED_WRITE); + if (ret) { + key_put(dest_keyring); + return ret; + } + } } *_dest_keyring = dest_keyring; kleave(" [dk %d]", key_serial(dest_keyring)); - return; + return 0; } /* @@ -444,11 +467,15 @@ static struct key *construct_key_and_link(struct keyring_search_context *ctx, if (ctx->index_key.type == &key_type_keyring) return ERR_PTR(-EPERM); - user = key_user_lookup(current_fsuid()); - if (!user) - return ERR_PTR(-ENOMEM); + ret = construct_get_dest_keyring(&dest_keyring); + if (ret) + goto error; - construct_get_dest_keyring(&dest_keyring); + user = key_user_lookup(current_fsuid()); + if (!user) { + ret = -ENOMEM; + goto error_put_dest_keyring; + } ret = construct_alloc_key(ctx, dest_keyring, flags, user, &key); key_user_put(user); @@ -463,7 +490,7 @@ static struct key *construct_key_and_link(struct keyring_search_context *ctx, } else if (ret == -EINPROGRESS) { ret = 0; } else { - goto couldnt_alloc_key; + goto error_put_dest_keyring; } key_put(dest_keyring); @@ -473,8 +500,9 @@ static struct key *construct_key_and_link(struct keyring_search_context *ctx, construction_failed: key_negate_and_link(key, key_negative_timeout, NULL, NULL); key_put(key); -couldnt_alloc_key: +error_put_dest_keyring: key_put(dest_keyring); +error: kleave(" = %d", ret); return ERR_PTR(ret); }

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