This series contains 3 fixes somewhat related to various races we have
while handling fallback.
The root cause of the issues addressed here is that the check for
"we can fallback to tcp now" and the related action are not atomic. That
also applies to fallback due to MP_FAIL -- where the window race is even
wider.
Address the issue introducing an additional spinlock to bundle together
all the relevant events, as per patch 1 and 2. These fixes can be
backported up to v5.19 and v5.15.
Note that mptcp_disconnect() unconditionally clears the fallback status
(zeroing msk->flags) but don't touch the `allows_infinite_fallback`
flag. Such issue is addressed in patch 3, and can be backported up to
v5.17.
Signed-off-by: Matthieu Baerts (NGI0) <matttbe(a)kernel.org>
---
Paolo Abeni (3):
mptcp: make fallback action and fallback decision atomic
mptcp: plug races between subflow fail and subflow creation
mptcp: reset fallback status gracefully at disconnect() time
net/mptcp/options.c | 3 ++-
net/mptcp/pm.c | 8 +++++++-
net/mptcp/protocol.c | 56 ++++++++++++++++++++++++++++++++++++++++++++--------
net/mptcp/protocol.h | 29 ++++++++++++++++++++-------
net/mptcp/subflow.c | 30 +++++++++++++++++-----------
5 files changed, 98 insertions(+), 28 deletions(-)
---
base-commit: b640daa2822a39ff76e70200cb2b7b892b896dce
change-id: 20250714-net-mptcp-fallback-races-a99f171cf5ca
Best regards,
--
Matthieu Baerts (NGI0) <matttbe(a)kernel.org>
After a recent change in clang to expose uninitialized warnings from
const variables and pointers [1], there is a warning around crtc_state
in dpu_plane_virtual_atomic_check():
drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c:1145:6: error: variable 'crtc_state' is used uninitialized whenever 'if' condition is false [-Werror,-Wsometimes-uninitialized]
1145 | if (plane_state->crtc)
| ^~~~~~~~~~~~~~~~~
drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c:1149:58: note: uninitialized use occurs here
1149 | ret = dpu_plane_atomic_check_nosspp(plane, plane_state, crtc_state);
| ^~~~~~~~~~
drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c:1145:2: note: remove the 'if' if its condition is always true
1145 | if (plane_state->crtc)
| ^~~~~~~~~~~~~~~~~~~~~~
1146 | crtc_state = drm_atomic_get_new_crtc_state(state,
drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c:1139:35: note: initialize the variable 'crtc_state' to silence this warning
1139 | struct drm_crtc_state *crtc_state;
| ^
| = NULL
Initialize crtc_state to NULL like other places in the driver do, so
that it is consistently initialized.
Cc: stable(a)vger.kernel.org
Closes: https://github.com/ClangBuiltLinux/linux/issues/2106
Fixes: 774bcfb73176 ("drm/msm/dpu: add support for virtual planes")
Link: https://github.com/llvm/llvm-project/commit/2464313eef01c5b1edf0eccf57a32cd… [1]
Signed-off-by: Nathan Chancellor <nathan(a)kernel.org>
---
drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c
index 421138bc3cb7..30ff21c01a36 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c
@@ -1136,7 +1136,7 @@ static int dpu_plane_virtual_atomic_check(struct drm_plane *plane,
struct drm_plane_state *old_plane_state =
drm_atomic_get_old_plane_state(state, plane);
struct dpu_plane_state *pstate = to_dpu_plane_state(plane_state);
- struct drm_crtc_state *crtc_state;
+ struct drm_crtc_state *crtc_state = NULL;
int ret;
if (IS_ERR(plane_state))
---
base-commit: d3deabe4c619875714b9a844b1a3d9752dbae1dd
change-id: 20250715-drm-msm-fix-const-uninit-warning-2b93cef9f1c6
Best regards,
--
Nathan Chancellor <nathan(a)kernel.org>
After a recent change in clang to expose uninitialized warnings from
const variables [1], there is a warning from the if statement in
advisor_mode_show().
mm/ksm.c:3687:11: error: variable 'output' is used uninitialized whenever 'if' condition is false [-Werror,-Wsometimes-uninitialized]
3687 | else if (ksm_advisor == KSM_ADVISOR_SCAN_TIME)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
mm/ksm.c:3690:33: note: uninitialized use occurs here
3690 | return sysfs_emit(buf, "%s\n", output);
| ^~~~~~
Rewrite the if statement to implicitly make KSM_ADVISOR_NONE the else
branch so that it is obvious to the compiler that ksm_advisor can only
be KSM_ADVISOR_NONE or KSM_ADVISOR_SCAN_TIME due to the assignments in
advisor_mode_store().
Cc: stable(a)vger.kernel.org
Fixes: 66790e9a735b ("mm/ksm: add sysfs knobs for advisor")
Closes: https://github.com/ClangBuiltLinux/linux/issues/2100
Link: https://github.com/llvm/llvm-project/commit/2464313eef01c5b1edf0eccf57a32cd… [1]
Signed-off-by: Nathan Chancellor <nathan(a)kernel.org>
---
mm/ksm.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/mm/ksm.c b/mm/ksm.c
index 2b0210d41c55..160787bb121c 100644
--- a/mm/ksm.c
+++ b/mm/ksm.c
@@ -3682,10 +3682,10 @@ static ssize_t advisor_mode_show(struct kobject *kobj,
{
const char *output;
- if (ksm_advisor == KSM_ADVISOR_NONE)
- output = "[none] scan-time";
- else if (ksm_advisor == KSM_ADVISOR_SCAN_TIME)
+ if (ksm_advisor == KSM_ADVISOR_SCAN_TIME)
output = "none [scan-time]";
+ else
+ output = "[none] scan-time";
return sysfs_emit(buf, "%s\n", output);
}
---
base-commit: fed48693bdfeca666f7536ba88a05e9a4e5523b6
change-id: 20250715-ksm-fix-clang-21-uninit-warning-bea5a6b886ce
Best regards,
--
Nathan Chancellor <nathan(a)kernel.org>
The patch titled
Subject: mm/ksm: fix -Wsometimes-uninitialized from clang-21 in advisor_mode_show()
has been added to the -mm mm-hotfixes-unstable branch. Its filename is
mm-ksm-fix-wsometimes-uninitialized-from-clang-21-in-advisor_mode_show.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: Nathan Chancellor <nathan(a)kernel.org>
Subject: mm/ksm: fix -Wsometimes-uninitialized from clang-21 in advisor_mode_show()
Date: Tue, 15 Jul 2025 12:56:16 -0700
After a recent change in clang to expose uninitialized warnings from const
variables [1], there is a false positive warning from the if statement in
advisor_mode_show().
mm/ksm.c:3687:11: error: variable 'output' is used uninitialized whenever 'if' condition is false [-Werror,-Wsometimes-uninitialized]
3687 | else if (ksm_advisor == KSM_ADVISOR_SCAN_TIME)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
mm/ksm.c:3690:33: note: uninitialized use occurs here
3690 | return sysfs_emit(buf, "%s\n", output);
| ^~~~~~
Rewrite the if statement to implicitly make KSM_ADVISOR_NONE the else
branch so that it is obvious to the compiler that ksm_advisor can only be
KSM_ADVISOR_NONE or KSM_ADVISOR_SCAN_TIME due to the assignments in
advisor_mode_store().
Link: https://lkml.kernel.org/r/20250715-ksm-fix-clang-21-uninit-warning-v1-1-f44…
Fixes: 66790e9a735b ("mm/ksm: add sysfs knobs for advisor")
Signed-off-by: Nathan Chancellor <nathan(a)kernel.org>
Closes: https://github.com/ClangBuiltLinux/linux/issues/2100
Link: https://github.com/llvm/llvm-project/commit/2464313eef01c5b1edf0eccf57a32cd… [1]
Cc: Chengming Zhou <chengming.zhou(a)linux.dev>
Cc: David Hildenbrand <david(a)redhat.com>
Cc: Stefan Roesch <shr(a)devkernel.io>
Cc: xu xin <xu.xin16(a)zte.com.cn>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
mm/ksm.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
--- a/mm/ksm.c~mm-ksm-fix-wsometimes-uninitialized-from-clang-21-in-advisor_mode_show
+++ a/mm/ksm.c
@@ -3669,10 +3669,10 @@ static ssize_t advisor_mode_show(struct
{
const char *output;
- if (ksm_advisor == KSM_ADVISOR_NONE)
- output = "[none] scan-time";
- else if (ksm_advisor == KSM_ADVISOR_SCAN_TIME)
+ if (ksm_advisor == KSM_ADVISOR_SCAN_TIME)
output = "none [scan-time]";
+ else
+ output = "[none] scan-time";
return sysfs_emit(buf, "%s\n", output);
}
_
Patches currently in -mm which might be from nathan(a)kernel.org are
mm-ksm-fix-wsometimes-uninitialized-from-clang-21-in-advisor_mode_show.patch
panic-add-panic_sys_info-sysctl-to-take-human-readable-string-parameter-fix.patch
From: Ge Yang <yangge1116(a)126.com>
Since commit d228814b1913 ("efi/libstub: Add get_event_log() support
for CC platforms") reuses TPM2 support code for the CC platforms, when
launching a TDX virtual machine with coco measurement enabled, the
following error log is generated:
[Firmware Bug]: Failed to parse event in TPM Final Events Log
Call Trace:
efi_config_parse_tables()
efi_tpm_eventlog_init()
tpm2_calc_event_log_size()
__calc_tpm2_event_size()
The pcr_idx value in the Intel TDX log header is 1, causing the function
__calc_tpm2_event_size() to fail to recognize the log header, ultimately
leading to the "Failed to parse event in TPM Final Events Log" error.
Intel misread the spec and wrongly sets pcrIndex to 1 in the header and
since they did this, we fear others might, so we're relaxing the header
check. There's no danger of this causing problems because we check for
the TCG_SPECID_SIG signature as the next thing.
Fixes: d228814b1913 ("efi/libstub: Add get_event_log() support for CC platforms")
Signed-off-by: Ge Yang <yangge1116(a)126.com>
Cc: stable(a)vger.kernel.org
---
V6:
- improve commit message suggested by James
V5:
- remove the pcr_index check without adding any replacement checks suggested by James and Sathyanarayanan
V4:
- remove cc_platform_has(CC_ATTR_GUEST_STATE_ENCRYPT) suggested by Ard
V3:
- fix build error
V2:
- limit the fix for CC only suggested by Jarkko and Sathyanarayanan
include/linux/tpm_eventlog.h | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/include/linux/tpm_eventlog.h b/include/linux/tpm_eventlog.h
index 891368e..05c0ae5 100644
--- a/include/linux/tpm_eventlog.h
+++ b/include/linux/tpm_eventlog.h
@@ -202,8 +202,7 @@ static __always_inline u32 __calc_tpm2_event_size(struct tcg_pcr_event2_head *ev
event_type = event->event_type;
/* Verify that it's the log header */
- if (event_header->pcr_idx != 0 ||
- event_header->event_type != NO_ACTION ||
+ if (event_header->event_type != NO_ACTION ||
memcmp(event_header->digest, zero_digest, sizeof(zero_digest))) {
size = 0;
goto out;
--
2.7.4
From: "Borislav Petkov (AMD)" <bp(a)alien8.de>
VERW_CLEAR is supposed to be set only by the hypervisor to denote TSA
mitigation support to a guest. SQ_NO and L1_NO are both synthesizable,
and are going to be set by hw CPUID on future machines.
So keep the kvm_cpu_cap_init_kvm_defined() invocation *and* set them
when synthesized.
This fix is stable-only.
Co-developed-by: Jinpu Wang <jinpu.wang(a)ionos.com>
Signed-off-by: Jinpu Wang <jinpu.wang(a)ionos.com>
Signed-off-by: Borislav Petkov (AMD) <bp(a)alien8.de>
---
arch/x86/kvm/cpuid.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index 02196db26a08..8f587c5bb6bc 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -822,6 +822,7 @@ void kvm_set_cpu_caps(void)
kvm_cpu_cap_check_and_set(X86_FEATURE_SBPB);
kvm_cpu_cap_check_and_set(X86_FEATURE_IBPB_BRTYPE);
kvm_cpu_cap_check_and_set(X86_FEATURE_SRSO_NO);
+ kvm_cpu_cap_check_and_set(X86_FEATURE_VERW_CLEAR);
kvm_cpu_cap_init_kvm_defined(CPUID_8000_0022_EAX,
F(PERFMON_V2)
@@ -831,6 +832,9 @@ void kvm_set_cpu_caps(void)
F(TSA_SQ_NO) | F(TSA_L1_NO)
);
+ kvm_cpu_cap_check_and_set(X86_FEATURE_TSA_SQ_NO);
+ kvm_cpu_cap_check_and_set(X86_FEATURE_TSA_L1_NO);
+
/*
* Synthesize "LFENCE is serializing" into the AMD-defined entry in
* KVM's supported CPUID if the feature is reported as supported by the
--
2.43.0
This reverts commit e8afa1557f4f963c9a511bd2c6074a941c308685.
The dma_buf field in struct drm_gem_object is not stable over the
object instance's lifetime. The field becomes NULL when user space
releases the final GEM handle on the buffer object. This resulted
in a NULL-pointer deref.
Workarounds in commit 5307dce878d4 ("drm/gem: Acquire references on
GEM handles for framebuffers") and commit f6bfc9afc751 ("drm/framebuffer:
Acquire internal references on GEM handles") only solved the problem
partially. They especially don't work for buffer objects without a DRM
framebuffer associated.
Hence, this revert to going back to using .import_attach->dmabuf.
v3:
- cc stable
Signed-off-by: Thomas Zimmermann <tzimmermann(a)suse.de>
Reviewed-by: Simona Vetter <simona.vetter(a)ffwll.ch>
Acked-by: Christian König <christian.koenig(a)amd.com>
Cc: <stable(a)vger.kernel.org> # v6.15+
---
drivers/gpu/drm/drm_gem_dma_helper.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/drm_gem_dma_helper.c b/drivers/gpu/drm/drm_gem_dma_helper.c
index b7f033d4352a..4f0320df858f 100644
--- a/drivers/gpu/drm/drm_gem_dma_helper.c
+++ b/drivers/gpu/drm/drm_gem_dma_helper.c
@@ -230,7 +230,7 @@ void drm_gem_dma_free(struct drm_gem_dma_object *dma_obj)
if (drm_gem_is_imported(gem_obj)) {
if (dma_obj->vaddr)
- dma_buf_vunmap_unlocked(gem_obj->dma_buf, &map);
+ dma_buf_vunmap_unlocked(gem_obj->import_attach->dmabuf, &map);
drm_prime_gem_destroy(gem_obj, dma_obj->sgt);
} else if (dma_obj->vaddr) {
if (dma_obj->map_noncoherent)
--
2.50.0
This reverts commit 1a148af06000e545e714fe3210af3d77ff903c11.
The dma_buf field in struct drm_gem_object is not stable over the
object instance's lifetime. The field becomes NULL when user space
releases the final GEM handle on the buffer object. This resulted
in a NULL-pointer deref.
Workarounds in commit 5307dce878d4 ("drm/gem: Acquire references on
GEM handles for framebuffers") and commit f6bfc9afc751 ("drm/framebuffer:
Acquire internal references on GEM handles") only solved the problem
partially. They especially don't work for buffer objects without a DRM
framebuffer associated.
Hence, this revert to going back to using .import_attach->dmabuf.
v3:
- cc stable
Signed-off-by: Thomas Zimmermann <tzimmermann(a)suse.de>
Reviewed-by: Simona Vetter <simona.vetter(a)ffwll.ch>
Acked-by: Christian König <christian.koenig(a)amd.com>
Cc: <stable(a)vger.kernel.org> # v6.15+
---
drivers/gpu/drm/drm_gem_shmem_helper.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/drm_gem_shmem_helper.c b/drivers/gpu/drm/drm_gem_shmem_helper.c
index 8ac0b1fa5287..5d1349c34afd 100644
--- a/drivers/gpu/drm/drm_gem_shmem_helper.c
+++ b/drivers/gpu/drm/drm_gem_shmem_helper.c
@@ -351,7 +351,7 @@ int drm_gem_shmem_vmap_locked(struct drm_gem_shmem_object *shmem,
dma_resv_assert_held(obj->resv);
if (drm_gem_is_imported(obj)) {
- ret = dma_buf_vmap(obj->dma_buf, map);
+ ret = dma_buf_vmap(obj->import_attach->dmabuf, map);
} else {
pgprot_t prot = PAGE_KERNEL;
@@ -413,7 +413,7 @@ void drm_gem_shmem_vunmap_locked(struct drm_gem_shmem_object *shmem,
dma_resv_assert_held(obj->resv);
if (drm_gem_is_imported(obj)) {
- dma_buf_vunmap(obj->dma_buf, map);
+ dma_buf_vunmap(obj->import_attach->dmabuf, map);
} else {
dma_resv_assert_held(shmem->base.resv);
--
2.50.0
This reverts commit cce16fcd7446dcff7480cd9d2b6417075ed81065.
The dma_buf field in struct drm_gem_object is not stable over the
object instance's lifetime. The field becomes NULL when user space
releases the final GEM handle on the buffer object. This resulted
in a NULL-pointer deref.
Workarounds in commit 5307dce878d4 ("drm/gem: Acquire references on
GEM handles for framebuffers") and commit f6bfc9afc751 ("drm/framebuffer:
Acquire internal references on GEM handles") only solved the problem
partially. They especially don't work for buffer objects without a DRM
framebuffer associated.
Hence, this revert to going back to using .import_attach->dmabuf.
v3:
- cc stable
Signed-off-by: Thomas Zimmermann <tzimmermann(a)suse.de>
Reviewed-by: Simona Vetter <simona.vetter(a)ffwll.ch>
Acked-by: Christian König <christian.koenig(a)amd.com>
Cc: <stable(a)vger.kernel.org> # v6.15+
---
drivers/gpu/drm/drm_gem_framebuffer_helper.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/drm_gem_framebuffer_helper.c b/drivers/gpu/drm/drm_gem_framebuffer_helper.c
index 618ce725cd75..fefb2a0f6b40 100644
--- a/drivers/gpu/drm/drm_gem_framebuffer_helper.c
+++ b/drivers/gpu/drm/drm_gem_framebuffer_helper.c
@@ -420,6 +420,7 @@ EXPORT_SYMBOL(drm_gem_fb_vunmap);
static void __drm_gem_fb_end_cpu_access(struct drm_framebuffer *fb, enum dma_data_direction dir,
unsigned int num_planes)
{
+ struct dma_buf_attachment *import_attach;
struct drm_gem_object *obj;
int ret;
@@ -428,9 +429,10 @@ static void __drm_gem_fb_end_cpu_access(struct drm_framebuffer *fb, enum dma_dat
obj = drm_gem_fb_get_obj(fb, num_planes);
if (!obj)
continue;
+ import_attach = obj->import_attach;
if (!drm_gem_is_imported(obj))
continue;
- ret = dma_buf_end_cpu_access(obj->dma_buf, dir);
+ ret = dma_buf_end_cpu_access(import_attach->dmabuf, dir);
if (ret)
drm_err(fb->dev, "dma_buf_end_cpu_access(%u, %d) failed: %d\n",
ret, num_planes, dir);
@@ -453,6 +455,7 @@ static void __drm_gem_fb_end_cpu_access(struct drm_framebuffer *fb, enum dma_dat
*/
int drm_gem_fb_begin_cpu_access(struct drm_framebuffer *fb, enum dma_data_direction dir)
{
+ struct dma_buf_attachment *import_attach;
struct drm_gem_object *obj;
unsigned int i;
int ret;
@@ -463,9 +466,10 @@ int drm_gem_fb_begin_cpu_access(struct drm_framebuffer *fb, enum dma_data_direct
ret = -EINVAL;
goto err___drm_gem_fb_end_cpu_access;
}
+ import_attach = obj->import_attach;
if (!drm_gem_is_imported(obj))
continue;
- ret = dma_buf_begin_cpu_access(obj->dma_buf, dir);
+ ret = dma_buf_begin_cpu_access(import_attach->dmabuf, dir);
if (ret)
goto err___drm_gem_fb_end_cpu_access;
}
--
2.50.0
This reverts commit f83a9b8c7fd0557b0c50784bfdc1bbe9140c9bf8.
The dma_buf field in struct drm_gem_object is not stable over the
object instance's lifetime. The field becomes NULL when user space
releases the final GEM handle on the buffer object. This resulted
in a NULL-pointer deref.
Workarounds in commit 5307dce878d4 ("drm/gem: Acquire references on
GEM handles for framebuffers") and commit f6bfc9afc751 ("drm/framebuffer:
Acquire internal references on GEM handles") only solved the problem
partially. They especially don't work for buffer objects without a DRM
framebuffer associated.
Hence, this revert to going back to using .import_attach->dmabuf.
v3:
- cc stable
Signed-off-by: Thomas Zimmermann <tzimmermann(a)suse.de>
Reviewed-by: Simona Vetter <simona.vetter(a)ffwll.ch>
Acked-by: Christian König <christian.koenig(a)amd.com>
Cc: <stable(a)vger.kernel.org> # v6.15+
---
drivers/gpu/drm/drm_prime.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/drm_prime.c b/drivers/gpu/drm/drm_prime.c
index b703f83874e1..a23fc712a8b7 100644
--- a/drivers/gpu/drm/drm_prime.c
+++ b/drivers/gpu/drm/drm_prime.c
@@ -453,7 +453,13 @@ struct dma_buf *drm_gem_prime_handle_to_dmabuf(struct drm_device *dev,
}
mutex_lock(&dev->object_name_lock);
- /* re-export the original imported/exported object */
+ /* re-export the original imported object */
+ if (obj->import_attach) {
+ dmabuf = obj->import_attach->dmabuf;
+ get_dma_buf(dmabuf);
+ goto out_have_obj;
+ }
+
if (obj->dma_buf) {
get_dma_buf(obj->dma_buf);
dmabuf = obj->dma_buf;
--
2.50.0
The FRED specification v9.0 states that there is no need for FRED
event handlers to begin with ENDBR64, because in the presence of
supervisor indirect branch tracking, FRED event delivery does not
enter the WAIT_FOR_ENDBRANCH state.
As a result, remove ENDBR64 from FRED entry points.
Then add ANNOTATE_NOENDBR to indicate that FRED entry points will
never be used for indirect calls to suppress an objtool warning.
This change implies that any indirect CALL/JMP to FRED entry points
causes #CP in the presence of supervisor indirect branch tracking.
Credit goes to Jennifer Miller <jmill(a)asu.edu> and other contributors
from Arizona State University whose work led to this change.
Fixes: 14619d912b65 ("x86/fred: FRED entry/exit and dispatch code")
Link: https://lore.kernel.org/linux-hardening/Z60NwR4w%2F28Z7XUa@ubun/
Reviewed-by: H. Peter Anvin (Intel) <hpa(a)zytor.com>
Signed-off-by: Xin Li (Intel) <xin(a)zytor.com>
Cc: Jennifer Miller <jmill(a)asu.edu>
Cc: Peter Zijlstra <peterz(a)infradead.org>
Cc: Andrew Cooper <andrew.cooper3(a)citrix.com>
Cc: H. Peter Anvin <hpa(a)zytor.com>
Cc: stable(a)vger.kernel.org # v6.9+
---
Change in v2:
*) CC stable and add a fixes tag (PeterZ).
---
arch/x86/entry/entry_64_fred.S | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/x86/entry/entry_64_fred.S b/arch/x86/entry/entry_64_fred.S
index 29c5c32c16c3..907bd233c6c1 100644
--- a/arch/x86/entry/entry_64_fred.S
+++ b/arch/x86/entry/entry_64_fred.S
@@ -16,7 +16,7 @@
.macro FRED_ENTER
UNWIND_HINT_END_OF_STACK
- ENDBR
+ ANNOTATE_NOENDBR
PUSH_AND_CLEAR_REGS
movq %rsp, %rdi /* %rdi -> pt_regs */
.endm
--
2.50.1
The patch below does not apply to the 6.1-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>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y
git checkout FETCH_HEAD
git cherry-pick -x fea18c686320a53fce7ad62a87a3e1d10ad02f31
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025071315-rural-exploring-3260@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From fea18c686320a53fce7ad62a87a3e1d10ad02f31 Mon Sep 17 00:00:00 2001
From: Alexander Gordeev <agordeev(a)linux.ibm.com>
Date: Mon, 23 Jun 2025 09:57:21 +0200
Subject: [PATCH] mm/vmalloc: leave lazy MMU mode on PTE mapping error
vmap_pages_pte_range() enters the lazy MMU mode, but fails to leave it in
case an error is encountered.
Link: https://lkml.kernel.org/r/20250623075721.2817094-1-agordeev@linux.ibm.com
Fixes: 2ba3e6947aed ("mm/vmalloc: track which page-table levels were modified")
Signed-off-by: Alexander Gordeev <agordeev(a)linux.ibm.com>
Reported-by: kernel test robot <lkp(a)intel.com>
Reported-by: Dan Carpenter <dan.carpenter(a)linaro.org>
Closes: https://lore.kernel.org/r/202506132017.T1l1l6ME-lkp@intel.com/
Reviewed-by: Ryan Roberts <ryan.roberts(a)arm.com>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index ab986dd09b6a..6dbcdceecae1 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -514,6 +514,7 @@ static int vmap_pages_pte_range(pmd_t *pmd, unsigned long addr,
unsigned long end, pgprot_t prot, struct page **pages, int *nr,
pgtbl_mod_mask *mask)
{
+ int err = 0;
pte_t *pte;
/*
@@ -530,12 +531,18 @@ static int vmap_pages_pte_range(pmd_t *pmd, unsigned long addr,
do {
struct page *page = pages[*nr];
- if (WARN_ON(!pte_none(ptep_get(pte))))
- return -EBUSY;
- if (WARN_ON(!page))
- return -ENOMEM;
- if (WARN_ON(!pfn_valid(page_to_pfn(page))))
- return -EINVAL;
+ if (WARN_ON(!pte_none(ptep_get(pte)))) {
+ err = -EBUSY;
+ break;
+ }
+ if (WARN_ON(!page)) {
+ err = -ENOMEM;
+ break;
+ }
+ if (WARN_ON(!pfn_valid(page_to_pfn(page)))) {
+ err = -EINVAL;
+ break;
+ }
set_pte_at(&init_mm, addr, pte, mk_pte(page, prot));
(*nr)++;
@@ -543,7 +550,8 @@ static int vmap_pages_pte_range(pmd_t *pmd, unsigned long addr,
arch_leave_lazy_mmu_mode();
*mask |= PGTBL_PTE_MODIFIED;
- return 0;
+
+ return err;
}
static int vmap_pages_pmd_range(pud_t *pud, unsigned long addr,
The patch below does not apply to the 5.15-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>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y
git checkout FETCH_HEAD
git cherry-pick -x fea18c686320a53fce7ad62a87a3e1d10ad02f31
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025071316-jawed-backward-2063@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From fea18c686320a53fce7ad62a87a3e1d10ad02f31 Mon Sep 17 00:00:00 2001
From: Alexander Gordeev <agordeev(a)linux.ibm.com>
Date: Mon, 23 Jun 2025 09:57:21 +0200
Subject: [PATCH] mm/vmalloc: leave lazy MMU mode on PTE mapping error
vmap_pages_pte_range() enters the lazy MMU mode, but fails to leave it in
case an error is encountered.
Link: https://lkml.kernel.org/r/20250623075721.2817094-1-agordeev@linux.ibm.com
Fixes: 2ba3e6947aed ("mm/vmalloc: track which page-table levels were modified")
Signed-off-by: Alexander Gordeev <agordeev(a)linux.ibm.com>
Reported-by: kernel test robot <lkp(a)intel.com>
Reported-by: Dan Carpenter <dan.carpenter(a)linaro.org>
Closes: https://lore.kernel.org/r/202506132017.T1l1l6ME-lkp@intel.com/
Reviewed-by: Ryan Roberts <ryan.roberts(a)arm.com>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index ab986dd09b6a..6dbcdceecae1 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -514,6 +514,7 @@ static int vmap_pages_pte_range(pmd_t *pmd, unsigned long addr,
unsigned long end, pgprot_t prot, struct page **pages, int *nr,
pgtbl_mod_mask *mask)
{
+ int err = 0;
pte_t *pte;
/*
@@ -530,12 +531,18 @@ static int vmap_pages_pte_range(pmd_t *pmd, unsigned long addr,
do {
struct page *page = pages[*nr];
- if (WARN_ON(!pte_none(ptep_get(pte))))
- return -EBUSY;
- if (WARN_ON(!page))
- return -ENOMEM;
- if (WARN_ON(!pfn_valid(page_to_pfn(page))))
- return -EINVAL;
+ if (WARN_ON(!pte_none(ptep_get(pte)))) {
+ err = -EBUSY;
+ break;
+ }
+ if (WARN_ON(!page)) {
+ err = -ENOMEM;
+ break;
+ }
+ if (WARN_ON(!pfn_valid(page_to_pfn(page)))) {
+ err = -EINVAL;
+ break;
+ }
set_pte_at(&init_mm, addr, pte, mk_pte(page, prot));
(*nr)++;
@@ -543,7 +550,8 @@ static int vmap_pages_pte_range(pmd_t *pmd, unsigned long addr,
arch_leave_lazy_mmu_mode();
*mask |= PGTBL_PTE_MODIFIED;
- return 0;
+
+ return err;
}
static int vmap_pages_pmd_range(pud_t *pud, unsigned long addr,
The patch below does not apply to the 5.10-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>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.10.y
git checkout FETCH_HEAD
git cherry-pick -x fea18c686320a53fce7ad62a87a3e1d10ad02f31
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025071323-settling-calculus-60b3@gregkh' --subject-prefix 'PATCH 5.10.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From fea18c686320a53fce7ad62a87a3e1d10ad02f31 Mon Sep 17 00:00:00 2001
From: Alexander Gordeev <agordeev(a)linux.ibm.com>
Date: Mon, 23 Jun 2025 09:57:21 +0200
Subject: [PATCH] mm/vmalloc: leave lazy MMU mode on PTE mapping error
vmap_pages_pte_range() enters the lazy MMU mode, but fails to leave it in
case an error is encountered.
Link: https://lkml.kernel.org/r/20250623075721.2817094-1-agordeev@linux.ibm.com
Fixes: 2ba3e6947aed ("mm/vmalloc: track which page-table levels were modified")
Signed-off-by: Alexander Gordeev <agordeev(a)linux.ibm.com>
Reported-by: kernel test robot <lkp(a)intel.com>
Reported-by: Dan Carpenter <dan.carpenter(a)linaro.org>
Closes: https://lore.kernel.org/r/202506132017.T1l1l6ME-lkp@intel.com/
Reviewed-by: Ryan Roberts <ryan.roberts(a)arm.com>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index ab986dd09b6a..6dbcdceecae1 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -514,6 +514,7 @@ static int vmap_pages_pte_range(pmd_t *pmd, unsigned long addr,
unsigned long end, pgprot_t prot, struct page **pages, int *nr,
pgtbl_mod_mask *mask)
{
+ int err = 0;
pte_t *pte;
/*
@@ -530,12 +531,18 @@ static int vmap_pages_pte_range(pmd_t *pmd, unsigned long addr,
do {
struct page *page = pages[*nr];
- if (WARN_ON(!pte_none(ptep_get(pte))))
- return -EBUSY;
- if (WARN_ON(!page))
- return -ENOMEM;
- if (WARN_ON(!pfn_valid(page_to_pfn(page))))
- return -EINVAL;
+ if (WARN_ON(!pte_none(ptep_get(pte)))) {
+ err = -EBUSY;
+ break;
+ }
+ if (WARN_ON(!page)) {
+ err = -ENOMEM;
+ break;
+ }
+ if (WARN_ON(!pfn_valid(page_to_pfn(page)))) {
+ err = -EINVAL;
+ break;
+ }
set_pte_at(&init_mm, addr, pte, mk_pte(page, prot));
(*nr)++;
@@ -543,7 +550,8 @@ static int vmap_pages_pte_range(pmd_t *pmd, unsigned long addr,
arch_leave_lazy_mmu_mode();
*mask |= PGTBL_PTE_MODIFIED;
- return 0;
+
+ return err;
}
static int vmap_pages_pmd_range(pud_t *pud, unsigned long addr,
Hi Sasha,
the changes in hci_request.c look quite different from what I submitted for mainline
(and also from the version for 6.6 LTS). Are you sure that everything went correctly?
regards,
Christian
On Monday, 14 July 2025, 19:37:07 CEST, Sasha Levin wrote:
> This is a note to let you know that I've just added the patch titled
>
> Bluetooth: HCI: Set extended advertising data synchronously
>
> to the 5.10-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:
> bluetooth-hci-set-extended-advertising-data-synchron.patch
> and it can be found in the queue-5.10 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.
>
>
>
> commit 8766e406adb9b3c4bd8c0506a71bbbf99a43906d
> Author: Christian Eggers <ceggers(a)arri.de>
> Date: Sat Jul 12 02:08:03 2025 -0400
>
> Bluetooth: HCI: Set extended advertising data synchronously
>
> [ Upstream commit 89fb8acc38852116d38d721ad394aad7f2871670 ]
>
> Currently, for controllers with extended advertising, the advertising
> data is set in the asynchronous response handler for extended
> adverstising params. As most advertising settings are performed in a
> synchronous context, the (asynchronous) setting of the advertising data
> is done too late (after enabling the advertising).
>
> Move setting of adverstising data from asynchronous response handler
> into synchronous context to fix ordering of HCI commands.
>
> Signed-off-by: Christian Eggers <ceggers(a)arri.de>
> Fixes: a0fb3726ba55 ("Bluetooth: Use Set ext adv/scan rsp data if controller supports")
> Cc: stable(a)vger.kernel.org
> v2: https://lore.kernel.org/linux-bluetooth/20250626115209.17839-1-ceggers@arri…
> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz(a)intel.com>
> Signed-off-by: Sasha Levin <sashal(a)kernel.org>
>
> diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
> index 7f26c1aab9a06..2cc4aaba09abe 100644
> --- a/net/bluetooth/hci_event.c
> +++ b/net/bluetooth/hci_event.c
> @@ -1726,36 +1726,6 @@ static void hci_cc_set_adv_param(struct hci_dev *hdev, struct sk_buff *skb)
> hci_dev_unlock(hdev);
> }
>
> -static void hci_cc_set_ext_adv_param(struct hci_dev *hdev, struct sk_buff *skb)
> -{
> - struct hci_rp_le_set_ext_adv_params *rp = (void *) skb->data;
> - struct hci_cp_le_set_ext_adv_params *cp;
> - struct adv_info *adv_instance;
> -
> - BT_DBG("%s status 0x%2.2x", hdev->name, rp->status);
> -
> - if (rp->status)
> - return;
> -
> - cp = hci_sent_cmd_data(hdev, HCI_OP_LE_SET_EXT_ADV_PARAMS);
> - if (!cp)
> - return;
> -
> - hci_dev_lock(hdev);
> - hdev->adv_addr_type = cp->own_addr_type;
> - if (!hdev->cur_adv_instance) {
> - /* Store in hdev for instance 0 */
> - hdev->adv_tx_power = rp->tx_power;
> - } else {
> - adv_instance = hci_find_adv_instance(hdev,
> - hdev->cur_adv_instance);
> - if (adv_instance)
> - adv_instance->tx_power = rp->tx_power;
> - }
> - /* Update adv data as tx power is known now */
> - hci_req_update_adv_data(hdev, hdev->cur_adv_instance);
> - hci_dev_unlock(hdev);
> -}
>
> static void hci_cc_read_rssi(struct hci_dev *hdev, struct sk_buff *skb)
> {
> @@ -3601,9 +3571,6 @@ static void hci_cmd_complete_evt(struct hci_dev *hdev, struct sk_buff *skb,
> hci_cc_le_read_num_adv_sets(hdev, skb);
> break;
>
> - case HCI_OP_LE_SET_EXT_ADV_PARAMS:
> - hci_cc_set_ext_adv_param(hdev, skb);
> - break;
>
> case HCI_OP_LE_SET_EXT_ADV_ENABLE:
> hci_cc_le_set_ext_adv_enable(hdev, skb);
> diff --git a/net/bluetooth/hci_request.c b/net/bluetooth/hci_request.c
> index 7ce6db1ac558a..743ba58941f8b 100644
> --- a/net/bluetooth/hci_request.c
> +++ b/net/bluetooth/hci_request.c
> @@ -2179,6 +2179,9 @@ int __hci_req_setup_ext_adv_instance(struct hci_request *req, u8 instance)
>
> hci_req_add(req, HCI_OP_LE_SET_EXT_ADV_PARAMS, sizeof(cp), &cp);
>
> + /* Update adv data after setting ext adv params */
> + __hci_req_update_adv_data(req, instance);
> +
> if (own_addr_type == ADDR_LE_DEV_RANDOM &&
> bacmp(&random_addr, BDADDR_ANY)) {
> struct hci_cp_le_set_adv_set_rand_addr cp;
>
Hi,
in the last week, after updating to 6.6.92, we’ve encountered a number of VMs reporting temporarily hung tasks blocking the whole system for a few minutes. They unblock by themselves and have similar tracebacks.
The IO PSIs show 100% pressure for that time, but the underlying devices are still processing read and write IO (well within their capacity). I’ve eliminated the underlying storage (Ceph) as the source of problems as I couldn’t find any latency outliers or significant queuing during that time.
I’ve seen somewhat similar reports on 6.6.88 and 6.6.77, but those might have been different outliers.
I’m attaching 3 logs - my intuition and the data so far leads me to consider this might be a kernel bug. I haven’t found a way to reproduce this, yet.
Regards,
Christian
--
Christian Theune · ct(a)flyingcircus.io · +49 345 219401 0
Flying Circus Internet Operations GmbH · https://flyingcircus.io
Leipziger Str. 70/71 · 06108 Halle (Saale) · Deutschland
HR Stendal HRB 21169 · Geschäftsführer: Christian Theune, Christian Zagrodnick