February 2025 - Linux-stable-mirror

[REGRESSION] Chrome and VSCode breakage with the commit b9b588f22a0c

by Takashi Iwai

Hi, we received a bug report showing the regression on 6.13.1 kernel against 6.13.0. The symptom is that Chrome and VSCode stopped working with Gnome Scaling, as reported on openSUSE Tumbleweed bug tracker https://bugzilla.suse.com/show_bug.cgi?id=1236943 Quoting from there: """ I use the latest TW on Gnome with a 4K display and 150% scaling. Everything has been working fine, but recently both Chrome and VSCode (installed from official non-openSUSE channels) stopped working with Scaling. .... I am using VSCode with: `--enable-features=UseOzonePlatform --enable-features=WaylandWindowDecorations --ozone-platform-hint=auto` and for Chrome, I select `Preferred Ozone platform` == `Wayland`. """ Surprisingly, the bisection pointed to the backport of the commit b9b588f22a0c049a14885399e27625635ae6ef91 ("libfs: Use d_children list to iterate simple_offset directories"). Indeed, the revert of this patch on the latest 6.13.4 was confirmed to fix the issue. Also, the reporter verified that the latest 6.14-rc release is still affected, too. For now I have no concrete idea how the patch could break the behavior of a graphical application like the above. Let us know if you need something for debugging. (Or at easiest, join to the bugzilla entry and ask there; or open another bug report at whatever you like.) BTW, I'll be traveling tomorrow, so my reply will be delayed. thanks, Takashi #regzbot introduced: b9b588f22a0c049a14885399e27625635ae6ef91 #regzbot monitor: https://bugzilla.suse.com/show_bug.cgi?id=1236943

3 months, 3 weeks

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Please backport "drm: select DRM_KMS_HELPER from DRM_GEM_SHMEM_HELPER" to 6.13.x

by NoisyCoil

Hello. The build (actually, linking) failure described in [1] affects current stable (6.13.4). Could the commit that fixes it in mainline, namely, c40ca9ef7c5c9bbb0d2f7774c87417cc4f1713bf ("drm: select DRM_KMS_HELPER from DRM_GEM_SHMEM_HELPER") be backported to 6.13.x, please? Thank you. [1] https://lore.kernel.org/all/20250121-greedy-flounder-of-abundance-4d2ee8-mk…

3 months, 3 weeks

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+ mm-abort-vma_modify-on-merge-out-of-memory-failure.patch added to mm-hotfixes-unstable branch

by Andrew Morton

The patch titled Subject: mm: abort vma_modify() on merge out of memory failure has been added to the -mm mm-hotfixes-unstable branch. Its filename is mm-abort-vma_modify-on-merge-out-of-memory-failure.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patche… This patch will later appear in the mm-hotfixes-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com> Subject: mm: abort vma_modify() on merge out of memory failure Date: Sat, 22 Feb 2025 16:19:52 +0000 The remainder of vma_modify() relies upon the vmg state remaining pristine after a merge attempt. Usually this is the case, however in the one edge case scenario of a merge attempt failing not due to the specified range being unmergeable, but rather due to an out of memory error arising when attempting to commit the merge, this assumption becomes untrue. This results in vmg->start, end being modified, and thus the proceeding attempts to split the VMA will be done with invalid start/end values. Thankfully, it is likely practically impossible for us to hit this in reality, as it would require a maple tree node pre-allocation failure that would likely never happen due to it being 'too small to fail', i.e. the kernel would simply keep retrying reclaim until it succeeded. However, this scenario remains theoretically possible, and what we are doing here is wrong so we must correct it. The safest option is, when this scenario occurs, to simply give up the operation. If we cannot allocate memory to merge, then we cannot allocate memory to split either (perhaps moreso!). Any scenario where this would be happening would be under very extreme (likely fatal) memory pressure, so it's best we give up early. So there is no doubt it is appropriate to simply bail out in this scenario. However, in general we must if at all possible never assume VMG state is stable after a merge attempt, since merge operations update VMG fields. As a result, additionally also make this clear by storing start, end in local variables. The issue was reported originally by syzkaller, and by Brad Spengler (via an off-list discussion), and in both instances it manifested as a triggering of the assert: VM_WARN_ON_VMG(start >= end, vmg); In vma_merge_existing_range(). It seems at least one scenario in which this is occurring is one in which the merge being attempted is due to an madvise() across multiple VMAs which looks like this: start end |<------>| |----------|------| | vma | next | |----------|------| When madvise_walk_vmas() is invoked, we first find vma in the above (determining prev to be equal to vma as we are offset into vma), and then enter the loop. We determine the end of vma that forms part of the range we are madvise()'ing by setting 'tmp' to this value: /* Here vma->vm_start <= start < (end|vma->vm_end) */ tmp = vma->vm_end; We then invoke the madvise() operation via visit(), letting prev get updated to point to vma as part of the operation: /* Here vma->vm_start <= start < tmp <= (end|vma->vm_end). */ error = visit(vma, &prev, start, tmp, arg); Where the visit() function pointer in this instance is madvise_vma_behavior(). As observed in syzkaller reports, it is ultimately madvise_update_vma() that is invoked, calling vma_modify_flags_name() and vma_modify() in turn. Then, in vma_modify(), we attempt the merge: merged = vma_merge_existing_range(vmg); if (merged) return merged; We invoke this with vmg->start, end set to start, tmp as such: start tmp |<--->| |----------|------| | vma | next | |----------|------| We find ourselves in the merge right scenario, but the one in which we cannot remove the middle (we are offset into vma). Here we have a special case where vmg->start, end get set to perhaps unintuitive values - we intended to shrink the middle VMA and expand the next. This means vmg->start, end are set to... vma->vm_start, start. Now the commit_merge() fails, and vmg->start, end are left like this. This means we return to the rest of vma_modify() with vmg->start, end (here denoted as start', end') set as: start' end' |<-->| |----------|------| | vma | next | |----------|------| So we now erroneously try to split accordingly. This is where the unfortunate stuff begins. We start with: /* Split any preceding portion of the VMA. */ if (vma->vm_start < vmg->start) { ... } This doesn't trigger as we are no longer offset into vma at the start. But then we invoke: /* Split any trailing portion of the VMA. */ if (vma->vm_end > vmg->end) { ... } Which does get invoked. This leaves us with: start' end' |<-->| |----|-----|------| | vma| new | next | |----|-----|------| We then return ultimately to madvise_walk_vmas(). Here 'new' is unknown, and putting back the values known in this function we are faced with: start tmp end | | | |----|-----|------| | vma| new | next | |----|-----|------| prev Then: start = tmp; So: start end | | |----|-----|------| | vma| new | next | |----|-----|------| prev The following code does not cause anything to happen: if (prev && start < prev->vm_end) start = prev->vm_end; if (start >= end) break; And then we invoke: if (prev) vma = find_vma(mm, prev->vm_end); Which is where a problem occurs - we don't know about 'new' so we essentially look for the vma after prev, which is new, whereas we actually intended to discover next! So we end up with: start end | | |----|-----|------| |prev| vma | next | |----|-----|------| And we have successfully bypassed all of the checks madvise_walk_vmas() has to ensure early exit should we end up moving out of range. We loop around, and hit: /* Here vma->vm_start <= start < (end|vma->vm_end) */ tmp = vma->vm_end; Oh dear. Now we have: tmp start end | | |----|-----|------| |prev| vma | next | |----|-----|------| We then invoke: /* Here vma->vm_start <= start < tmp <= (end|vma->vm_end). */ error = visit(vma, &prev, start, tmp, arg); Where start == tmp. That is, a zero range. This is not good. We invoke visit() which is madvise_vma_behavior() which does not check the range (for good reason, it assumes all checks have been done before it was called), which in turn finally calls madvise_update_vma(). The madvise_update_vma() function calls vma_modify_flags_name() in turn, which ultimately invokes vma_modify() with... start == end. vma_modify() calls vma_merge_existing_range() and finally we hit: VM_WARN_ON_VMG(start >= end, vmg); Which triggers, as start == end. While it might be useful to add some CONFIG_DEBUG_VM asserts in these instances to catch this kind of error, since we have just eliminated any possibility of that happening, we will add such asserts separately as to reduce churn and aid backporting. Link: https://lkml.kernel.org/r/20250222161952.41957-1-lorenzo.stoakes@oracle.com Fixes: 2f1c6611b0a8 ("mm: introduce vma_merge_struct and abstract vma_merge(),vma_modify()") Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com> Tested-by: Brad Spengler <brad.spengler(a)opensrcsec.com> Reported-by: Brad Spengler <brad.spengler(a)opensrcsec.com> Reported-by: syzbot+46423ed8fa1f1148c6e4(a)syzkaller.appspotmail.com Closes: https://lore.kernel.org/linux-mm/6774c98f.050a0220.25abdd.0991.GAE@google.c… Cc: Jann Horn <jannh(a)google.com> Cc: Liam Howlett <liam.howlett(a)oracle.com> Cc: Vlastimil Babka <vbabka(a)suse.cz> Cc: <stable(a)vger.kernel.org> Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> --- mm/vma.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) --- a/mm/vma.c~mm-abort-vma_modify-on-merge-out-of-memory-failure +++ a/mm/vma.c @@ -1509,24 +1509,28 @@ int do_vmi_munmap(struct vma_iterator *v static struct vm_area_struct *vma_modify(struct vma_merge_struct *vmg) { struct vm_area_struct *vma = vmg->vma; + unsigned long start = vmg->start; + unsigned long end = vmg->end; struct vm_area_struct *merged; /* First, try to merge. */ merged = vma_merge_existing_range(vmg); if (merged) return merged; + if (vmg_nomem(vmg)) + return ERR_PTR(-ENOMEM); /* Split any preceding portion of the VMA. */ - if (vma->vm_start < vmg->start) { - int err = split_vma(vmg->vmi, vma, vmg->start, 1); + if (vma->vm_start < start) { + int err = split_vma(vmg->vmi, vma, start, 1); if (err) return ERR_PTR(err); } /* Split any trailing portion of the VMA. */ - if (vma->vm_end > vmg->end) { - int err = split_vma(vmg->vmi, vma, vmg->end, 0); + if (vma->vm_end > end) { + int err = split_vma(vmg->vmi, vma, end, 0); if (err) return ERR_PTR(err); _ Patches currently in -mm which might be from lorenzo.stoakes(a)oracle.com are mm-abort-vma_modify-on-merge-out-of-memory-failure.patch mm-simplify-vma-merge-structure-and-expand-comments.patch mm-further-refactor-commit_merge.patch mm-eliminate-adj_start-parameter-from-commit_merge.patch mm-make-vmg-target-consistent-and-further-simplify-commit_merge.patch mm-completely-abstract-unnecessary-adj_start-calculation.patch mm-madvise-split-out-mmap-locking-operations-for-madvise-fix.patch mm-use-read-write_once-for-vma-vm_flags-on-migrate-mprotect.patch mm-refactor-rmap_walk_file-to-separate-out-traversal-logic.patch mm-provide-mapping_wrprotect_range-function.patch fb_defio-do-not-use-deprecated-page-mapping-index-fields.patch fb_defio-do-not-use-deprecated-page-mapping-index-fields-fix.patch mm-allow-guard-regions-in-file-backed-and-read-only-mappings.patch selftests-mm-rename-guard-pages-to-guard-regions.patch tools-selftests-expand-all-guard-region-tests-to-file-backed.patch tools-selftests-add-file-shmem-backed-mapping-guard-region-tests.patch

3 months, 3 weeks

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[PATCH v2 0/5] arm64: dts: rockchip: pinmux fixes and support for 2 adapters for Theobroma boards

by Quentin Schulz

This is based on top of https://git.kernel.org/pub/scm/linux/kernel/git/mmind/linux-rockchip.git/lo… 6ee0b9ad3995 ("arm64: dts: rockchip: Add rng node to RK3588") as it depends on the (merged) series from https://lore.kernel.org/all/20250211-pre-ict-jaguar-v6-0-4484b0f88cfc@cherr… Patches for Haikou Video Demo adapter for PX30 Ringneck and RK3399 Puma (patches 4 and 5) also depend on the following patch series: https://lore.kernel.org/linux-devicetree/20250220-pca976x-reset-driver-v1-0… This fixes incorrect pinmux on UART0 and UART5 for PX30 Ringneck on Haikou. This adds support for the HAIKOU-LVDS-9904379 adapter for PX30 Ringneck fitted on a Haikou carrierboard. Additionally, this adds support for Haikou Video Demo adapter on PX30 Ringneck and RK3399 Puma fitted on a Haikou carrierboard. Notably missing from the overlay is the OV5675 camera module which expects 19.2MHz which we cannot exactly feed right now. Modifications to the OV5675 drivers will be made so it's more flexible and then support for the camera module will be added. This adapter has a 720x1280 DSI display with a GT911 touchscreen, a GPIO-controllable LED and an I2C GPIO expander. Support for this adapter on RK3588 Tiger is being added in a separate patch series[1]. Note that the DSI panel currently is glitchy on both PX30 Ringneck and RK3399 Puma but this is being tackled in another series[2]. Since this will not be fixed through DT properties for the panel, adding the DT nodes for the DSI panel even if not perfect right now seems acceptable to me. [1] https://lore.kernel.org/linux-rockchip/20241127143719.660658-1-heiko@sntech… [2] https://lore.kernel.org/r/20240626084722.832763-1-heiko@sntech.de Signed-off-by: Quentin Schulz <quentin.schulz(a)cherry.de> --- Changes in v2: - rename uart5_rts_gpio to uart5_rts_pin to stop triggering a false positive of the dtschema checker, - remove PU from uart5_rts_pin, - Link to v1: https://lore.kernel.org/r/20250220-ringneck-dtbos-v1-0-25c97f2385e6@cherry.… --- Quentin Schulz (5): arm64: dts: rockchip: fix pinmux of UART0 for PX30 Ringneck on Haikou arm64: dts: rockchip: fix pinmux of UART5 for PX30 Ringneck on Haikou arm64: dts: rockchip: add support for HAIKOU-LVDS-9904379 adapter for PX30 Ringneck arm64: dts: rockchip: add overlay for PX30 Ringneck Haikou Video Demo adapter arm64: dts: rockchip: add overlay for RK3399 Puma Haikou Video Demo adapter arch/arm64/boot/dts/rockchip/Makefile | 15 ++ .../px30-ringneck-haikou-lvds-9904379.dtso | 130 ++++++++++++++ .../rockchip/px30-ringneck-haikou-video-demo.dtso | 190 +++++++++++++++++++++ .../boot/dts/rockchip/px30-ringneck-haikou.dts | 10 +- .../rockchip/rk3399-puma-haikou-video-demo.dtso | 166 ++++++++++++++++++ 5 files changed, 510 insertions(+), 1 deletion(-) --- base-commit: 6ee0b9ad3995ee5fa229035c69013b7dd0d3634b change-id: 20250128-ringneck-dtbos-98064839355e prerequisite-change-id: 20250219-pca976x-reset-driver-c9aa95869426:v2 prerequisite-patch-id: 25c49bae002eb11bc6fec479f49f5e3b28b8f403 prerequisite-patch-id: 58e9acffbbd052710bfe672c99ef05f59b1978a6 Best regards, -- Quentin Schulz <quentin.schulz(a)cherry.de>

3 months, 3 weeks

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[PATCH 6.6] x86/cpu/kvm: SRSO: Fix possible missing IBPB on VM-Exit

by Patrick Bellasi

commit 318e8c339c9a0891c389298bb328ed0762a9935e upstream. In [1] the meaning of the synthetic IBPB flags has been redefined for a better separation of concerns: - ENTRY_IBPB -- issue IBPB on entry only - IBPB_ON_VMEXIT -- issue IBPB on VM-Exit only and the Retbleed mitigations have been updated to match this new semantics. Commit [2] was merged shortly before [1], and their interaction was not handled properly. This resulted in IBPB not being triggered on VM-Exit in all SRSO mitigation configs requesting an IBPB there. Specifically, an IBPB on VM-Exit is triggered only when X86_FEATURE_IBPB_ON_VMEXIT is set. However: - X86_FEATURE_IBPB_ON_VMEXIT is not set for "spec_rstack_overflow=ibpb", because before [1] having X86_FEATURE_ENTRY_IBPB was enough. Hence, an IBPB is triggered on entry but the expected IBPB on VM-exit is not. - X86_FEATURE_IBPB_ON_VMEXIT is not set also when "spec_rstack_overflow=ibpb-vmexit" if X86_FEATURE_ENTRY_IBPB is already set. That's because before [1] this was effectively redundant. Hence, e.g. a "retbleed=ibpb spec_rstack_overflow=bpb-vmexit" config mistakenly reports the machine still vulnerable to SRSO, despite an IBPB being triggered both on entry and VM-Exit, because of the Retbleed selected mitigation config. - UNTRAIN_RET_VM won't still actually do anything unless CONFIG_MITIGATION_IBPB_ENTRY is set. For "spec_rstack_overflow=ibpb", enable IBPB on both entry and VM-Exit and clear X86_FEATURE_RSB_VMEXIT which is made superfluous by X86_FEATURE_IBPB_ON_VMEXIT. This effectively makes this mitigation option similar to the one for 'retbleed=ibpb', thus re-order the code for the RETBLEED_MITIGATION_IBPB option to be less confusing by having all features enabling before the disabling of the not needed ones. For "spec_rstack_overflow=ibpb-vmexit", guard this mitigation setting with CONFIG_MITIGATION_IBPB_ENTRY to ensure UNTRAIN_RET_VM sequence is effectively compiled in. Drop instead the CONFIG_MITIGATION_SRSO guard, since none of the SRSO compile cruft is required in this configuration. Also, check only that the required microcode is present to effectively enabled the IBPB on VM-Exit. Finally, update the KConfig description for CONFIG_MITIGATION_IBPB_ENTRY to list also all SRSO config settings enabled by this guard. Fixes: 864bcaa38ee4 ("x86/cpu/kvm: Provide UNTRAIN_RET_VM") [1] Fixes: d893832d0e1e ("x86/srso: Add IBPB on VMEXIT") [2] Reported-by: Yosry Ahmed <yosryahmed(a)google.com> Signed-off-by: Patrick Bellasi <derkling(a)google.com> Reviewed-by: Borislav Petkov (AMD) <bp(a)alien8.de> Cc: stable(a)kernel.org Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org> --- arch/x86/Kconfig | 3 ++- arch/x86/kernel/cpu/bugs.c | 21 ++++++++++++++------- 2 files changed, 16 insertions(+), 8 deletions(-) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 05c82fd5d0f60..989d432b58345 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -2514,7 +2514,8 @@ config CPU_IBPB_ENTRY depends on CPU_SUP_AMD && X86_64 default y help - Compile the kernel with support for the retbleed=ibpb mitigation. + Compile the kernel with support for the retbleed=ibpb and + spec_rstack_overflow={ibpb,ibpb-vmexit} mitigations. config CPU_IBRS_ENTRY bool "Enable IBRS on kernel entry" diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c index 7b5ba5b8592a2..7df458a6553eb 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -1113,6 +1113,8 @@ static void __init retbleed_select_mitigation(void) case RETBLEED_MITIGATION_IBPB: setup_force_cpu_cap(X86_FEATURE_ENTRY_IBPB); + setup_force_cpu_cap(X86_FEATURE_IBPB_ON_VMEXIT); + mitigate_smt = true; /* * IBPB on entry already obviates the need for @@ -1122,9 +1124,6 @@ static void __init retbleed_select_mitigation(void) setup_clear_cpu_cap(X86_FEATURE_UNRET); setup_clear_cpu_cap(X86_FEATURE_RETHUNK); - setup_force_cpu_cap(X86_FEATURE_IBPB_ON_VMEXIT); - mitigate_smt = true; - /* * There is no need for RSB filling: entry_ibpb() ensures * all predictions, including the RSB, are invalidated, @@ -2626,6 +2625,7 @@ static void __init srso_select_mitigation(void) if (IS_ENABLED(CONFIG_CPU_IBPB_ENTRY)) { if (has_microcode) { setup_force_cpu_cap(X86_FEATURE_ENTRY_IBPB); + setup_force_cpu_cap(X86_FEATURE_IBPB_ON_VMEXIT); srso_mitigation = SRSO_MITIGATION_IBPB; /* @@ -2635,6 +2635,13 @@ static void __init srso_select_mitigation(void) */ setup_clear_cpu_cap(X86_FEATURE_UNRET); setup_clear_cpu_cap(X86_FEATURE_RETHUNK); + + /* + * There is no need for RSB filling: entry_ibpb() ensures + * all predictions, including the RSB, are invalidated, + * regardless of IBPB implementation. + */ + setup_clear_cpu_cap(X86_FEATURE_RSB_VMEXIT); } } else { pr_err("WARNING: kernel not compiled with CPU_IBPB_ENTRY.\n"); @@ -2643,8 +2650,8 @@ static void __init srso_select_mitigation(void) break; case SRSO_CMD_IBPB_ON_VMEXIT: - if (IS_ENABLED(CONFIG_CPU_SRSO)) { - if (!boot_cpu_has(X86_FEATURE_ENTRY_IBPB) && has_microcode) { + if (IS_ENABLED(CONFIG_CPU_IBPB_ENTRY)) { + if (has_microcode) { setup_force_cpu_cap(X86_FEATURE_IBPB_ON_VMEXIT); srso_mitigation = SRSO_MITIGATION_IBPB_ON_VMEXIT; @@ -2656,9 +2663,9 @@ static void __init srso_select_mitigation(void) setup_clear_cpu_cap(X86_FEATURE_RSB_VMEXIT); } } else { - pr_err("WARNING: kernel not compiled with CPU_SRSO.\n"); + pr_err("WARNING: kernel not compiled with CPU_IBPB_ENTRY.\n"); goto pred_cmd; - } + } break; default: -- 2.48.1.601.g30ceb7b040-goog

3 months, 3 weeks

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[PATCH 5.10] x86/cpu/kvm: SRSO: Fix possible missing IBPB on VM-Exit

by Patrick Bellasi

commit 318e8c339c9a0891c389298bb328ed0762a9935e upstream. In [1] the meaning of the synthetic IBPB flags has been redefined for a better separation of concerns: - ENTRY_IBPB -- issue IBPB on entry only - IBPB_ON_VMEXIT -- issue IBPB on VM-Exit only and the Retbleed mitigations have been updated to match this new semantics. Commit [2] was merged shortly before [1], and their interaction was not handled properly. This resulted in IBPB not being triggered on VM-Exit in all SRSO mitigation configs requesting an IBPB there. Specifically, an IBPB on VM-Exit is triggered only when X86_FEATURE_IBPB_ON_VMEXIT is set. However: - X86_FEATURE_IBPB_ON_VMEXIT is not set for "spec_rstack_overflow=ibpb", because before [1] having X86_FEATURE_ENTRY_IBPB was enough. Hence, an IBPB is triggered on entry but the expected IBPB on VM-exit is not. - X86_FEATURE_IBPB_ON_VMEXIT is not set also when "spec_rstack_overflow=ibpb-vmexit" if X86_FEATURE_ENTRY_IBPB is already set. That's because before [1] this was effectively redundant. Hence, e.g. a "retbleed=ibpb spec_rstack_overflow=bpb-vmexit" config mistakenly reports the machine still vulnerable to SRSO, despite an IBPB being triggered both on entry and VM-Exit, because of the Retbleed selected mitigation config. - UNTRAIN_RET_VM won't still actually do anything unless CONFIG_MITIGATION_IBPB_ENTRY is set. For "spec_rstack_overflow=ibpb", enable IBPB on both entry and VM-Exit and clear X86_FEATURE_RSB_VMEXIT which is made superfluous by X86_FEATURE_IBPB_ON_VMEXIT. This effectively makes this mitigation option similar to the one for 'retbleed=ibpb', thus re-order the code for the RETBLEED_MITIGATION_IBPB option to be less confusing by having all features enabling before the disabling of the not needed ones. For "spec_rstack_overflow=ibpb-vmexit", guard this mitigation setting with CONFIG_MITIGATION_IBPB_ENTRY to ensure UNTRAIN_RET_VM sequence is effectively compiled in. Drop instead the CONFIG_MITIGATION_SRSO guard, since none of the SRSO compile cruft is required in this configuration. Also, check only that the required microcode is present to effectively enabled the IBPB on VM-Exit. Finally, update the KConfig description for CONFIG_MITIGATION_IBPB_ENTRY to list also all SRSO config settings enabled by this guard. Fixes: 864bcaa38ee4 ("x86/cpu/kvm: Provide UNTRAIN_RET_VM") [1] Fixes: d893832d0e1e ("x86/srso: Add IBPB on VMEXIT") [2] Reported-by: Yosry Ahmed <yosryahmed(a)google.com> Signed-off-by: Patrick Bellasi <derkling(a)google.com> Reviewed-by: Borislav Petkov (AMD) <bp(a)alien8.de> Cc: stable(a)kernel.org Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org> --- arch/x86/Kconfig | 3 ++- arch/x86/kernel/cpu/bugs.c | 20 ++++++++++++++------ 2 files changed, 16 insertions(+), 7 deletions(-) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 0c802ade80406..00ae2e2adcadb 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -2463,7 +2463,8 @@ config CPU_IBPB_ENTRY depends on CPU_SUP_AMD && X86_64 default y help - Compile the kernel with support for the retbleed=ibpb mitigation. + Compile the kernel with support for the retbleed=ibpb and + spec_rstack_overflow={ibpb,ibpb-vmexit} mitigations. config CPU_IBRS_ENTRY bool "Enable IBRS on kernel entry" diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c index 0b7f6bcbb8ea9..725f827718a71 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -1061,6 +1061,8 @@ static void __init retbleed_select_mitigation(void) case RETBLEED_MITIGATION_IBPB: setup_force_cpu_cap(X86_FEATURE_ENTRY_IBPB); + setup_force_cpu_cap(X86_FEATURE_IBPB_ON_VMEXIT); + mitigate_smt = true; /* * IBPB on entry already obviates the need for @@ -1070,8 +1072,6 @@ static void __init retbleed_select_mitigation(void) setup_clear_cpu_cap(X86_FEATURE_UNRET); setup_clear_cpu_cap(X86_FEATURE_RETHUNK); - mitigate_smt = true; - /* * There is no need for RSB filling: entry_ibpb() ensures * all predictions, including the RSB, are invalidated, @@ -2469,6 +2469,7 @@ static void __init srso_select_mitigation(void) if (IS_ENABLED(CONFIG_CPU_IBPB_ENTRY)) { if (has_microcode) { setup_force_cpu_cap(X86_FEATURE_ENTRY_IBPB); + setup_force_cpu_cap(X86_FEATURE_IBPB_ON_VMEXIT); srso_mitigation = SRSO_MITIGATION_IBPB; /* @@ -2478,6 +2479,13 @@ static void __init srso_select_mitigation(void) */ setup_clear_cpu_cap(X86_FEATURE_UNRET); setup_clear_cpu_cap(X86_FEATURE_RETHUNK); + + /* + * There is no need for RSB filling: entry_ibpb() ensures + * all predictions, including the RSB, are invalidated, + * regardless of IBPB implementation. + */ + setup_clear_cpu_cap(X86_FEATURE_RSB_VMEXIT); } } else { pr_err("WARNING: kernel not compiled with CPU_IBPB_ENTRY.\n"); @@ -2486,8 +2494,8 @@ static void __init srso_select_mitigation(void) break; case SRSO_CMD_IBPB_ON_VMEXIT: - if (IS_ENABLED(CONFIG_CPU_SRSO)) { - if (!boot_cpu_has(X86_FEATURE_ENTRY_IBPB) && has_microcode) { + if (IS_ENABLED(CONFIG_CPU_IBPB_ENTRY)) { + if (has_microcode) { setup_force_cpu_cap(X86_FEATURE_IBPB_ON_VMEXIT); srso_mitigation = SRSO_MITIGATION_IBPB_ON_VMEXIT; @@ -2499,9 +2507,9 @@ static void __init srso_select_mitigation(void) setup_clear_cpu_cap(X86_FEATURE_RSB_VMEXIT); } } else { - pr_err("WARNING: kernel not compiled with CPU_SRSO.\n"); + pr_err("WARNING: kernel not compiled with CPU_IBPB_ENTRY.\n"); goto pred_cmd; - } + } break; default: -- 2.48.1.601.g30ceb7b040-goog

3 months, 3 weeks

2
1
0 0

[PATCH 6.1] x86/cpu/kvm: SRSO: Fix possible missing IBPB on VM-Exit

by Patrick Bellasi

commit 318e8c339c9a0891c389298bb328ed0762a9935e upstream. In [1] the meaning of the synthetic IBPB flags has been redefined for a better separation of concerns: - ENTRY_IBPB -- issue IBPB on entry only - IBPB_ON_VMEXIT -- issue IBPB on VM-Exit only and the Retbleed mitigations have been updated to match this new semantics. Commit [2] was merged shortly before [1], and their interaction was not handled properly. This resulted in IBPB not being triggered on VM-Exit in all SRSO mitigation configs requesting an IBPB there. Specifically, an IBPB on VM-Exit is triggered only when X86_FEATURE_IBPB_ON_VMEXIT is set. However: - X86_FEATURE_IBPB_ON_VMEXIT is not set for "spec_rstack_overflow=ibpb", because before [1] having X86_FEATURE_ENTRY_IBPB was enough. Hence, an IBPB is triggered on entry but the expected IBPB on VM-exit is not. - X86_FEATURE_IBPB_ON_VMEXIT is not set also when "spec_rstack_overflow=ibpb-vmexit" if X86_FEATURE_ENTRY_IBPB is already set. That's because before [1] this was effectively redundant. Hence, e.g. a "retbleed=ibpb spec_rstack_overflow=bpb-vmexit" config mistakenly reports the machine still vulnerable to SRSO, despite an IBPB being triggered both on entry and VM-Exit, because of the Retbleed selected mitigation config. - UNTRAIN_RET_VM won't still actually do anything unless CONFIG_MITIGATION_IBPB_ENTRY is set. For "spec_rstack_overflow=ibpb", enable IBPB on both entry and VM-Exit and clear X86_FEATURE_RSB_VMEXIT which is made superfluous by X86_FEATURE_IBPB_ON_VMEXIT. This effectively makes this mitigation option similar to the one for 'retbleed=ibpb', thus re-order the code for the RETBLEED_MITIGATION_IBPB option to be less confusing by having all features enabling before the disabling of the not needed ones. For "spec_rstack_overflow=ibpb-vmexit", guard this mitigation setting with CONFIG_MITIGATION_IBPB_ENTRY to ensure UNTRAIN_RET_VM sequence is effectively compiled in. Drop instead the CONFIG_MITIGATION_SRSO guard, since none of the SRSO compile cruft is required in this configuration. Also, check only that the required microcode is present to effectively enabled the IBPB on VM-Exit. Finally, update the KConfig description for CONFIG_MITIGATION_IBPB_ENTRY to list also all SRSO config settings enabled by this guard. Fixes: 864bcaa38ee4 ("x86/cpu/kvm: Provide UNTRAIN_RET_VM") [1] Fixes: d893832d0e1e ("x86/srso: Add IBPB on VMEXIT") [2] Reported-by: Yosry Ahmed <yosryahmed(a)google.com> Signed-off-by: Patrick Bellasi <derkling(a)google.com> Reviewed-by: Borislav Petkov (AMD) <bp(a)alien8.de> Cc: stable(a)kernel.org Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org> --- arch/x86/Kconfig | 3 ++- arch/x86/kernel/cpu/bugs.c | 20 ++++++++++++++------ 2 files changed, 16 insertions(+), 7 deletions(-) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 49cea5b81649d..ca8dd7e5585f0 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -2506,7 +2506,8 @@ config CPU_IBPB_ENTRY depends on CPU_SUP_AMD && X86_64 default y help - Compile the kernel with support for the retbleed=ibpb mitigation. + Compile the kernel with support for the retbleed=ibpb and + spec_rstack_overflow={ibpb,ibpb-vmexit} mitigations. config CPU_IBRS_ENTRY bool "Enable IBRS on kernel entry" diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c index fa2045ad408a7..03221a060ae77 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -1092,6 +1092,8 @@ static void __init retbleed_select_mitigation(void) case RETBLEED_MITIGATION_IBPB: setup_force_cpu_cap(X86_FEATURE_ENTRY_IBPB); + setup_force_cpu_cap(X86_FEATURE_IBPB_ON_VMEXIT); + mitigate_smt = true; /* * IBPB on entry already obviates the need for @@ -1101,8 +1103,6 @@ static void __init retbleed_select_mitigation(void) setup_clear_cpu_cap(X86_FEATURE_UNRET); setup_clear_cpu_cap(X86_FEATURE_RETHUNK); - mitigate_smt = true; - /* * There is no need for RSB filling: entry_ibpb() ensures * all predictions, including the RSB, are invalidated, @@ -2607,6 +2607,7 @@ static void __init srso_select_mitigation(void) if (IS_ENABLED(CONFIG_CPU_IBPB_ENTRY)) { if (has_microcode) { setup_force_cpu_cap(X86_FEATURE_ENTRY_IBPB); + setup_force_cpu_cap(X86_FEATURE_IBPB_ON_VMEXIT); srso_mitigation = SRSO_MITIGATION_IBPB; /* @@ -2616,6 +2617,13 @@ static void __init srso_select_mitigation(void) */ setup_clear_cpu_cap(X86_FEATURE_UNRET); setup_clear_cpu_cap(X86_FEATURE_RETHUNK); + + /* + * There is no need for RSB filling: entry_ibpb() ensures + * all predictions, including the RSB, are invalidated, + * regardless of IBPB implementation. + */ + setup_clear_cpu_cap(X86_FEATURE_RSB_VMEXIT); } } else { pr_err("WARNING: kernel not compiled with CPU_IBPB_ENTRY.\n"); @@ -2624,8 +2632,8 @@ static void __init srso_select_mitigation(void) break; case SRSO_CMD_IBPB_ON_VMEXIT: - if (IS_ENABLED(CONFIG_CPU_SRSO)) { - if (!boot_cpu_has(X86_FEATURE_ENTRY_IBPB) && has_microcode) { + if (IS_ENABLED(CONFIG_CPU_IBPB_ENTRY)) { + if (has_microcode) { setup_force_cpu_cap(X86_FEATURE_IBPB_ON_VMEXIT); srso_mitigation = SRSO_MITIGATION_IBPB_ON_VMEXIT; @@ -2637,9 +2645,9 @@ static void __init srso_select_mitigation(void) setup_clear_cpu_cap(X86_FEATURE_RSB_VMEXIT); } } else { - pr_err("WARNING: kernel not compiled with CPU_SRSO.\n"); + pr_err("WARNING: kernel not compiled with CPU_IBPB_ENTRY.\n"); goto pred_cmd; - } + } break; default: -- 2.48.1.601.g30ceb7b040-goog

3 months, 3 weeks

2
1
0 0

[PATCH 5.15] x86/cpu/kvm: SRSO: Fix possible missing IBPB on VM-Exit

by Patrick Bellasi

commit 318e8c339c9a0891c389298bb328ed0762a9935e upstream. In [1] the meaning of the synthetic IBPB flags has been redefined for a better separation of concerns: - ENTRY_IBPB -- issue IBPB on entry only - IBPB_ON_VMEXIT -- issue IBPB on VM-Exit only and the Retbleed mitigations have been updated to match this new semantics. Commit [2] was merged shortly before [1], and their interaction was not handled properly. This resulted in IBPB not being triggered on VM-Exit in all SRSO mitigation configs requesting an IBPB there. Specifically, an IBPB on VM-Exit is triggered only when X86_FEATURE_IBPB_ON_VMEXIT is set. However: - X86_FEATURE_IBPB_ON_VMEXIT is not set for "spec_rstack_overflow=ibpb", because before [1] having X86_FEATURE_ENTRY_IBPB was enough. Hence, an IBPB is triggered on entry but the expected IBPB on VM-exit is not. - X86_FEATURE_IBPB_ON_VMEXIT is not set also when "spec_rstack_overflow=ibpb-vmexit" if X86_FEATURE_ENTRY_IBPB is already set. That's because before [1] this was effectively redundant. Hence, e.g. a "retbleed=ibpb spec_rstack_overflow=bpb-vmexit" config mistakenly reports the machine still vulnerable to SRSO, despite an IBPB being triggered both on entry and VM-Exit, because of the Retbleed selected mitigation config. - UNTRAIN_RET_VM won't still actually do anything unless CONFIG_MITIGATION_IBPB_ENTRY is set. For "spec_rstack_overflow=ibpb", enable IBPB on both entry and VM-Exit and clear X86_FEATURE_RSB_VMEXIT which is made superfluous by X86_FEATURE_IBPB_ON_VMEXIT. This effectively makes this mitigation option similar to the one for 'retbleed=ibpb', thus re-order the code for the RETBLEED_MITIGATION_IBPB option to be less confusing by having all features enabling before the disabling of the not needed ones. For "spec_rstack_overflow=ibpb-vmexit", guard this mitigation setting with CONFIG_MITIGATION_IBPB_ENTRY to ensure UNTRAIN_RET_VM sequence is effectively compiled in. Drop instead the CONFIG_MITIGATION_SRSO guard, since none of the SRSO compile cruft is required in this configuration. Also, check only that the required microcode is present to effectively enabled the IBPB on VM-Exit. Finally, update the KConfig description for CONFIG_MITIGATION_IBPB_ENTRY to list also all SRSO config settings enabled by this guard. Fixes: 864bcaa38ee4 ("x86/cpu/kvm: Provide UNTRAIN_RET_VM") [1] Fixes: d893832d0e1e ("x86/srso: Add IBPB on VMEXIT") [2] Reported-by: Yosry Ahmed <yosryahmed(a)google.com> Signed-off-by: Patrick Bellasi <derkling(a)google.com> Reviewed-by: Borislav Petkov (AMD) <bp(a)alien8.de> Cc: stable(a)kernel.org Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org> --- arch/x86/Kconfig | 3 ++- arch/x86/kernel/cpu/bugs.c | 20 ++++++++++++++------ 2 files changed, 16 insertions(+), 7 deletions(-) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 2f6312e7ce81f..90ac8d84389cf 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -2449,7 +2449,8 @@ config CPU_IBPB_ENTRY depends on CPU_SUP_AMD && X86_64 default y help - Compile the kernel with support for the retbleed=ibpb mitigation. + Compile the kernel with support for the retbleed=ibpb and + spec_rstack_overflow={ibpb,ibpb-vmexit} mitigations. config CPU_IBRS_ENTRY bool "Enable IBRS on kernel entry" diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c index f84d59cd180b3..dfc02fb32375c 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -1092,6 +1092,8 @@ static void __init retbleed_select_mitigation(void) case RETBLEED_MITIGATION_IBPB: setup_force_cpu_cap(X86_FEATURE_ENTRY_IBPB); + setup_force_cpu_cap(X86_FEATURE_IBPB_ON_VMEXIT); + mitigate_smt = true; /* * IBPB on entry already obviates the need for @@ -1101,8 +1103,6 @@ static void __init retbleed_select_mitigation(void) setup_clear_cpu_cap(X86_FEATURE_UNRET); setup_clear_cpu_cap(X86_FEATURE_RETHUNK); - mitigate_smt = true; - /* * There is no need for RSB filling: entry_ibpb() ensures * all predictions, including the RSB, are invalidated, @@ -2607,6 +2607,7 @@ static void __init srso_select_mitigation(void) if (IS_ENABLED(CONFIG_CPU_IBPB_ENTRY)) { if (has_microcode) { setup_force_cpu_cap(X86_FEATURE_ENTRY_IBPB); + setup_force_cpu_cap(X86_FEATURE_IBPB_ON_VMEXIT); srso_mitigation = SRSO_MITIGATION_IBPB; /* @@ -2616,6 +2617,13 @@ static void __init srso_select_mitigation(void) */ setup_clear_cpu_cap(X86_FEATURE_UNRET); setup_clear_cpu_cap(X86_FEATURE_RETHUNK); + + /* + * There is no need for RSB filling: entry_ibpb() ensures + * all predictions, including the RSB, are invalidated, + * regardless of IBPB implementation. + */ + setup_clear_cpu_cap(X86_FEATURE_RSB_VMEXIT); } } else { pr_err("WARNING: kernel not compiled with CPU_IBPB_ENTRY.\n"); @@ -2624,8 +2632,8 @@ static void __init srso_select_mitigation(void) break; case SRSO_CMD_IBPB_ON_VMEXIT: - if (IS_ENABLED(CONFIG_CPU_SRSO)) { - if (!boot_cpu_has(X86_FEATURE_ENTRY_IBPB) && has_microcode) { + if (IS_ENABLED(CONFIG_CPU_IBPB_ENTRY)) { + if (has_microcode) { setup_force_cpu_cap(X86_FEATURE_IBPB_ON_VMEXIT); srso_mitigation = SRSO_MITIGATION_IBPB_ON_VMEXIT; @@ -2637,9 +2645,9 @@ static void __init srso_select_mitigation(void) setup_clear_cpu_cap(X86_FEATURE_RSB_VMEXIT); } } else { - pr_err("WARNING: kernel not compiled with CPU_SRSO.\n"); + pr_err("WARNING: kernel not compiled with CPU_IBPB_ENTRY.\n"); goto pred_cmd; - } + } break; default: -- 2.48.1.601.g30ceb7b040-goog

3 months, 3 weeks

2
1
0 0

[PATCH 6.6 0/3] nilfs2: fix potential kernel BUG on rename operations

by Ryusuke Konishi

Please apply this series to the 6.6-stable tree. This series makes it possible to backport the fix for the BUG_ON check failure on rename operations reported by syzbot. The first two patches are for dependency resolution. Patch 3/3 is the target patch, and it has been tailored to avoid extensive page/folio conversion. This patch set has been tested against the latest 6.6.y. Thanks, Ryusuke Konishi Ryusuke Konishi (3): nilfs2: move page release outside of nilfs_delete_entry and nilfs_set_link nilfs2: eliminate staggered calls to kunmap in nilfs_rename nilfs2: handle errors that nilfs_prepare_chunk() may return fs/nilfs2/dir.c | 24 +++++++++++------------- fs/nilfs2/namei.c | 37 ++++++++++++++++++++----------------- fs/nilfs2/nilfs.h | 10 ++++++++-- 3 files changed, 39 insertions(+), 32 deletions(-) -- 2.43.5

3 months, 3 weeks

2
6
0 0

[PATCH 6.1.y] media: mediatek: vcodec: Fix H264 multi stateless decoder smatch warning

by jetlan9＠163.com

From: Yunfei Dong <yunfei.dong(a)mediatek.com> [ Upstream commit 9be85491619f1953b8a29590ca630be571941ffa ] Fix a smatch static checker warning on vdec_h264_req_multi_if.c. Which leads to a kernel crash when fb is NULL. Fixes: 397edc703a10 ("media: mediatek: vcodec: add h264 decoder driver for mt8186") Signed-off-by: Yunfei Dong <yunfei.dong(a)mediatek.com> Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno(a)collabora.com> Signed-off-by: Sebastian Fricke <sebastian.fricke(a)collabora.com> Signed-off-by: Hans Verkuil <hverkuil-cisco(a)xs4all.nl> [ drivers/media/platform/mediatek/vcodec/decoder/vdec/vdec_h264_req_multi_if.c is renamed from drivers/media/platform/mediatek/vcodec/vdec/vdec_h264_req_multi_if.c since 0934d3759615 ("media: mediatek: vcodec: separate decoder and encoder"). The path is changed accordingly to apply the patch on 6.1.y. ] Signed-off-by: Wenshan Lan <jetlan9(a)163.com> --- .../mediatek/vcodec/vdec/vdec_h264_req_multi_if.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/drivers/media/platform/mediatek/vcodec/vdec/vdec_h264_req_multi_if.c b/drivers/media/platform/mediatek/vcodec/vdec/vdec_h264_req_multi_if.c index 999ce7ee5fdc..6952875ca183 100644 --- a/drivers/media/platform/mediatek/vcodec/vdec/vdec_h264_req_multi_if.c +++ b/drivers/media/platform/mediatek/vcodec/vdec/vdec_h264_req_multi_if.c @@ -729,11 +729,16 @@ static int vdec_h264_slice_single_decode(void *h_vdec, struct mtk_vcodec_mem *bs return vpu_dec_reset(vpu); fb = inst->ctx->dev->vdec_pdata->get_cap_buffer(inst->ctx); + if (!fb) { + mtk_vcodec_err(inst, "fb buffer is NULL"); + return -ENOMEM; + } + src_buf_info = container_of(bs, struct mtk_video_dec_buf, bs_buffer); dst_buf_info = container_of(fb, struct mtk_video_dec_buf, frame_buffer); - y_fb_dma = fb ? (u64)fb->base_y.dma_addr : 0; - c_fb_dma = fb ? (u64)fb->base_c.dma_addr : 0; + y_fb_dma = fb->base_y.dma_addr; + c_fb_dma = fb->base_c.dma_addr; mtk_vcodec_debug(inst, "[h264-dec] [%d] y_dma=%llx c_dma=%llx", inst->ctx->decoded_frame_cnt, y_fb_dma, c_fb_dma); -- 2.34.1

3 months, 3 weeks

2
1
0 0

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