| Age | Commit message (Collapse) | Author | Files | Lines |
|---|
|
If no swap cache is reclaimed, cluster taken off from full_clusters list
will not be put in any list and we can't reclaime HAS_CACHE slots
efficiently. Do relocate_cluster for such cluster to avoid inefficiency.
Link: https://lkml.kernel.org/r/20250224113910.522439-1-shikemeng@huaweicloud.com
Fixes: 3b644773eefd ("mm, swap: reduce contention on device lock")
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Reviewed-by: Kairui Song <kasong@tencent.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
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@oracle.com>
Tested-by: Brad Spengler <brad.spengler@opensrcsec.com>
Reported-by: Brad Spengler <brad.spengler@opensrcsec.com>
Reported-by: syzbot+46423ed8fa1f1148c6e4@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/linux-mm/6774c98f.050a0220.25abdd.0991.GAE@google.com/
Cc: Jann Horn <jannh@google.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Since the introduction of commit c77c0a8ac4c52 ("mm/hugetlb: defer freeing
of huge pages if in non-task context"), which supports deferring the
freeing of hugetlb pages, the allocation of contiguous memory through
cma_alloc() may fail probabilistically.
In the CMA allocation process, if it is found that the CMA area is
occupied by in-use hugetlb folios, these in-use hugetlb folios need to be
migrated to another location. When there are no available hugetlb folios
in the free hugetlb pool during the migration of in-use hugetlb folios,
new folios are allocated from the buddy system. A temporary state is set
on the newly allocated folio. Upon completion of the hugetlb folio
migration, the temporary state is transferred from the new folios to the
old folios. Normally, when the old folios with the temporary state are
freed, it is directly released back to the buddy system. However, due to
the deferred freeing of hugetlb pages, the PageBuddy() check fails,
ultimately leading to the failure of cma_alloc().
Here is a simplified call trace illustrating the process:
cma_alloc()
->__alloc_contig_migrate_range() // Migrate in-use hugetlb folios
->unmap_and_move_huge_page()
->folio_putback_hugetlb() // Free old folios
->test_pages_isolated()
->__test_page_isolated_in_pageblock()
->PageBuddy(page) // Check if the page is in buddy
To resolve this issue, we have implemented a function named
wait_for_freed_hugetlb_folios(). This function ensures that the hugetlb
folios are properly released back to the buddy system after their
migration is completed. By invoking wait_for_freed_hugetlb_folios()
before calling PageBuddy(), we ensure that PageBuddy() will succeed.
Link: https://lkml.kernel.org/r/1739936804-18199-1-git-send-email-yangge1116@126.com
Fixes: c77c0a8ac4c5 ("mm/hugetlb: defer freeing of huge pages if in non-task context")
Signed-off-by: Ge Yang <yangge1116@126.com>
Reviewed-by: Muchun Song <muchun.song@linux.dev>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Barry Song <21cnbao@gmail.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Add a NULL check on the return value of swp_swap_info in __swap_duplicate
to prevent crashes caused by NULL pointer dereference.
The reason why swp_swap_info() returns NULL is unclear; it may be due
to CPU cache issues or DDR bit flips. The probability of this issue is
very small - it has been observed to occur approximately 1 in 500,000
times per week. The stack info we encountered is as follows:
Unable to handle kernel NULL pointer dereference at virtual address
0000000000000058
[RB/E]rb_sreason_str_set: sreason_str set null_pointer
Mem abort info:
ESR = 0x0000000096000005
EC = 0x25: DABT (current EL), IL = 32 bits
SET = 0, FnV = 0
EA = 0, S1PTW = 0
FSC = 0x05: level 1 translation fault
Data abort info:
ISV = 0, ISS = 0x00000005, ISS2 = 0x00000000
CM = 0, WnR = 0, TnD = 0, TagAccess = 0
GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
user pgtable: 4k pages, 39-bit VAs, pgdp=00000008a80e5000
[0000000000000058] pgd=0000000000000000, p4d=0000000000000000,
pud=0000000000000000
Internal error: Oops: 0000000096000005 [#1] PREEMPT SMP
Skip md ftrace buffer dump for: 0x1609e0
...
pc : swap_duplicate+0x44/0x164
lr : copy_page_range+0x508/0x1e78
sp : ffffffc0f2a699e0
x29: ffffffc0f2a699e0 x28: ffffff8a5b28d388 x27: ffffff8b06603388
x26: ffffffdf7291fe70 x25: 0000000000000006 x24: 0000000000100073
x23: 00000000002d2d2f x22: 0000000000000008 x21: 0000000000000000
x20: 00000000002d2d2f x19: 18000000002d2d2f x18: ffffffdf726faec0
x17: 0000000000000000 x16: 0010000000000001 x15: 0040000000000001
x14: 0400000000000001 x13: ff7ffffffffffb7f x12: ffeffffffffffbff
x11: ffffff8a5c7e1898 x10: 0000000000000018 x9 : 0000000000000006
x8 : 1800000000000000 x7 : 0000000000000000 x6 : ffffff8057c01f10
x5 : 000000000000a318 x4 : 0000000000000000 x3 : 0000000000000000
x2 : 0000006daf200000 x1 : 0000000000000001 x0 : 18000000002d2d2f
Call trace:
swap_duplicate+0x44/0x164
copy_page_range+0x508/0x1e78
copy_process+0x1278/0x21cc
kernel_clone+0x90/0x438
__arm64_sys_clone+0x5c/0x8c
invoke_syscall+0x58/0x110
do_el0_svc+0x8c/0xe0
el0_svc+0x38/0x9c
el0t_64_sync_handler+0x44/0xec
el0t_64_sync+0x1a8/0x1ac
Code: 9139c35a 71006f3f 54000568 f8797b55 (f9402ea8)
---[ end trace 0000000000000000 ]---
Kernel panic - not syncing: Oops: Fatal exception
SMP: stopping secondary CPUs
The patch seems to only provide a workaround, but there are no more
effective software solutions to handle the bit flips problem. This path
will change the issue from a system crash to a process exception, thereby
reducing the impact on the entire machine.
akpm: this is probably a kernel bug, but this patch keeps the system
running and doesn't reduce that bug's debuggability.
Link: https://lkml.kernel.org/r/e223b0e6ba2f4924984b1917cc717bd5@honor.com
Signed-off-by: gao xu <gaoxu2@honor.com>
Reviewed-by: Barry Song <baohua@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Yosry Ahmed <yosry.ahmed@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
kmsan_handle_dma() is used by virtio_ring() which can be built as a
module. kmsan_handle_dma() needs to be exported otherwise building the
virtio_ring fails.
Export kmsan_handle_dma for modules.
Link: https://lkml.kernel.org/r/20250218091411.MMS3wBN9@linutronix.de
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202502150634.qjxwSeJR-lkp@intel.com/
Fixes: 7ade4f10779c ("dma: kmsan: unpoison DMA mappings")
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitriy Vyukov <dvyukov@google.com>
Cc: Macro Elver <elver@google.com>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Fix incorrect reference to fault-injection docs
Link: https://lkml.kernel.org/r/20250215105106.734-1-ujwal.kundur@gmail.com
Signed-off-by: Ujwal Kundur <ujwal.kundur@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Commit b15c87263a69 ("hwpoison, memory_hotplug: allow hwpoisoned pages to
be offlined) add page poison checks in do_migrate_range in order to make
offline hwpoisoned page possible by introducing isolate_lru_page and
try_to_unmap for hwpoisoned page. However folio lock must be held before
calling try_to_unmap. Add it to fix this problem.
Warning will be produced if folio is not locked during unmap:
------------[ cut here ]------------
kernel BUG at ./include/linux/swapops.h:400!
Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP
Modules linked in:
CPU: 4 UID: 0 PID: 411 Comm: bash Tainted: G W 6.13.0-rc1-00016-g3c434c7ee82a-dirty #41
Tainted: [W]=WARN
Hardware name: QEMU QEMU Virtual Machine, BIOS 0.0.0 02/06/2015
pstate: 40400005 (nZcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : try_to_unmap_one+0xb08/0xd3c
lr : try_to_unmap_one+0x3dc/0xd3c
Call trace:
try_to_unmap_one+0xb08/0xd3c (P)
try_to_unmap_one+0x3dc/0xd3c (L)
rmap_walk_anon+0xdc/0x1f8
rmap_walk+0x3c/0x58
try_to_unmap+0x88/0x90
unmap_poisoned_folio+0x30/0xa8
do_migrate_range+0x4a0/0x568
offline_pages+0x5a4/0x670
memory_block_action+0x17c/0x374
memory_subsys_offline+0x3c/0x78
device_offline+0xa4/0xd0
state_store+0x8c/0xf0
dev_attr_store+0x18/0x2c
sysfs_kf_write+0x44/0x54
kernfs_fop_write_iter+0x118/0x1a8
vfs_write+0x3a8/0x4bc
ksys_write+0x6c/0xf8
__arm64_sys_write+0x1c/0x28
invoke_syscall+0x44/0x100
el0_svc_common.constprop.0+0x40/0xe0
do_el0_svc+0x1c/0x28
el0_svc+0x30/0xd0
el0t_64_sync_handler+0xc8/0xcc
el0t_64_sync+0x198/0x19c
Code: f9407be0 b5fff320 d4210000 17ffff97 (d4210000)
---[ end trace 0000000000000000 ]---
Link: https://lkml.kernel.org/r/20250217014329.3610326-4-mawupeng1@huawei.com
Fixes: b15c87263a69 ("hwpoison, memory_hotplug: allow hwpoisoned pages to be offlined")
Signed-off-by: Ma Wupeng <mawupeng1@huawei.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
If a folio has an increased reference count, folio_try_get() will acquire
it, perform necessary operations, and then release it. In the case of a
poisoned folio without an elevated reference count (which is unlikely for
memory-failure), folio_try_get() will simply bypass it.
Therefore, relocate the folio_try_get() function, responsible for checking
and acquiring this reference count at first.
Link: https://lkml.kernel.org/r/20250217014329.3610326-3-mawupeng1@huawei.com
Signed-off-by: Ma Wupeng <mawupeng1@huawei.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Patch series "mm: memory_failure: unmap poisoned folio during migrate
properly", v3.
Fix two bugs during folio migration if the folio is poisoned.
This patch (of 3):
Commit 6da6b1d4a7df ("mm/hwpoison: convert TTU_IGNORE_HWPOISON to
TTU_HWPOISON") introduce TTU_HWPOISON to replace TTU_IGNORE_HWPOISON in
order to stop send SIGBUS signal when accessing an error page after a
memory error on a clean folio. However during page migration, anon folio
must be set with TTU_HWPOISON during unmap_*(). For pagecache we need
some policy just like the one in hwpoison_user_mappings to set this flag.
So move this policy from hwpoison_user_mappings to unmap_poisoned_folio to
handle this warning properly.
Warning will be produced during unamp poison folio with the following log:
------------[ cut here ]------------
WARNING: CPU: 1 PID: 365 at mm/rmap.c:1847 try_to_unmap_one+0x8fc/0xd3c
Modules linked in:
CPU: 1 UID: 0 PID: 365 Comm: bash Tainted: G W 6.13.0-rc1-00018-gacdb4bbda7ab #42
Tainted: [W]=WARN
Hardware name: QEMU QEMU Virtual Machine, BIOS 0.0.0 02/06/2015
pstate: 20400005 (nzCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : try_to_unmap_one+0x8fc/0xd3c
lr : try_to_unmap_one+0x3dc/0xd3c
Call trace:
try_to_unmap_one+0x8fc/0xd3c (P)
try_to_unmap_one+0x3dc/0xd3c (L)
rmap_walk_anon+0xdc/0x1f8
rmap_walk+0x3c/0x58
try_to_unmap+0x88/0x90
unmap_poisoned_folio+0x30/0xa8
do_migrate_range+0x4a0/0x568
offline_pages+0x5a4/0x670
memory_block_action+0x17c/0x374
memory_subsys_offline+0x3c/0x78
device_offline+0xa4/0xd0
state_store+0x8c/0xf0
dev_attr_store+0x18/0x2c
sysfs_kf_write+0x44/0x54
kernfs_fop_write_iter+0x118/0x1a8
vfs_write+0x3a8/0x4bc
ksys_write+0x6c/0xf8
__arm64_sys_write+0x1c/0x28
invoke_syscall+0x44/0x100
el0_svc_common.constprop.0+0x40/0xe0
do_el0_svc+0x1c/0x28
el0_svc+0x30/0xd0
el0t_64_sync_handler+0xc8/0xcc
el0t_64_sync+0x198/0x19c
---[ end trace 0000000000000000 ]---
[mawupeng1@huawei.com: unmap_poisoned_folio(): remove shadowed local `mapping', per Miaohe]
Link: https://lkml.kernel.org/r/20250219060653.3849083-1-mawupeng1@huawei.com
Link: https://lkml.kernel.org/r/20250217014329.3610326-1-mawupeng1@huawei.com
Link: https://lkml.kernel.org/r/20250217014329.3610326-2-mawupeng1@huawei.com
Fixes: 6da6b1d4a7df ("mm/hwpoison: convert TTU_IGNORE_HWPOISON to TTU_HWPOISON")
Signed-off-by: Ma Wupeng <mawupeng1@huawei.com>
Suggested-by: David Hildenbrand <david@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: Ma Wupeng <mawupeng1@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
When update_mmu_cache_range() is called by update_mmu_cache(), the vmf
parameter is NULL, which will cause a NULL pointer dereference issue in
adjust_pte():
Unable to handle kernel NULL pointer dereference at virtual address 00000030 when read
Hardware name: Atmel AT91SAM9
PC is at update_mmu_cache_range+0x1e0/0x278
LR is at pte_offset_map_rw_nolock+0x18/0x2c
Call trace:
update_mmu_cache_range from remove_migration_pte+0x29c/0x2ec
remove_migration_pte from rmap_walk_file+0xcc/0x130
rmap_walk_file from remove_migration_ptes+0x90/0xa4
remove_migration_ptes from migrate_pages_batch+0x6d4/0x858
migrate_pages_batch from migrate_pages+0x188/0x488
migrate_pages from compact_zone+0x56c/0x954
compact_zone from compact_node+0x90/0xf0
compact_node from kcompactd+0x1d4/0x204
kcompactd from kthread+0x120/0x12c
kthread from ret_from_fork+0x14/0x38
Exception stack(0xc0d8bfb0 to 0xc0d8bff8)
To fix it, do not rely on whether 'ptl' is equal to decide whether to hold
the pte lock, but decide it by whether CONFIG_SPLIT_PTE_PTLOCKS is
enabled. In addition, if two vmas map to the same PTE page, there is no
need to hold the pte lock again, otherwise a deadlock will occur. Just
add the need_lock parameter to let adjust_pte() know this information.
Link: https://lkml.kernel.org/r/20250217024924.57996-1-zhengqi.arch@bytedance.com
Fixes: fc9c45b71f43 ("arm: adjust_pte() use pte_offset_map_rw_nolock()")
Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
Reported-by: Ezra Buehler <ezra.buehler@husqvarnagroup.com>
Closes: https://lore.kernel.org/lkml/CAM1KZSmZ2T_riHvay+7cKEFxoPgeVpHkVFTzVVEQ1BO0cLkHEQ@mail.gmail.com/
Acked-by: David Hildenbrand <david@redhat.com>
Tested-by: Ezra Buehler <ezra.buehler@husqvarnagroup.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Qi Zheng <zhengqi.arch@bytedance.com>
Cc: Russel King <linux@armlinux.org.uk>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Add check for the return value of __pgd_alloc() in pgd_alloc() to prevent
null pointer dereference.
Link: https://lkml.kernel.org/r/20250217160017.2375536-1-haoxiang_li2024@163.com
Fixes: a9b3c355c2e6 ("asm-generic: pgalloc: provide generic __pgd_{alloc,free}")
Signed-off-by: Haoxiang Li <haoxiang_li2024@163.com>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Qi Zheng <zhengqi.arch@bytedance.com>
Cc: Sam Creasey <sammy@sammy.net>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
damos_quota_goal.py selftest see if DAMOS quota goals tuning feature
increases or reduces the effective size quota for given score as expected.
The tuning feature sets the minimum quota size as one byte, so if the
effective size quota is already one, we cannot expect it further be
reduced. However the test is not aware of the edge case, and fails since
it shown no expected change of the effective quota. Handle the case by
updating the failure logic for no change to see if it was the case, and
simply skips to next test input.
Link: https://lkml.kernel.org/r/20250217182304.45215-1-sj@kernel.org
Fixes: f1c07c0a1662 ("selftests/damon: add a test for DAMOS quota goal")
Signed-off-by: SeongJae Park <sj@kernel.org>
Reported-by: kernel test robot <oliver.sang@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202502171423.b28a918d-lkp@intel.com
Cc: Shuah Khan <shuah@kernel.org>
Cc: <stable@vger.kernel.org> [6.10.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
This reverts commit a5c6bc590094a1a73cf6fa3f505e1945d2bf2461.
The general approach described in commit e076eaca5906 ("selftests: break
the dependency upon local header files") was taken one step too far here:
it should not have been extended to include the syscall numbers. This is
because doing so would require per-arch support in tools/include/uapi, and
no such support exists.
This revert fixes two separate reports of test failures, from Dave
Hansen[1], and Li Wang[2]. An excerpt of Dave's report:
Before this commit (a5c6bc590094a1a73cf6fa3f505e1945d2bf2461) things are
fine. But after, I get:
running PKEY tests for unsupported CPU/OS
An excerpt of Li's report:
I just found that mlock2_() return a wrong value in mlock2-test
[1] https://lore.kernel.org/dc585017-6740-4cab-a536-b12b37a7582d@intel.com
[2] https://lore.kernel.org/CAEemH2eW=UMu9+turT2jRie7+6ewUazXmA6kL+VBo3cGDGU6RA@mail.gmail.com
Link: https://lkml.kernel.org/r/20250214033850.235171-1-jhubbard@nvidia.com
Fixes: a5c6bc590094 ("selftests/mm: remove local __NR_* definitions")
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Li Wang <liwang@redhat.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jeff Xu <jeffxu@chromium.org>
Cc: Andrei Vagin <avagin@google.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Kees Cook <kees@kernel.org>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Muhammad Usama Anjum <usama.anjum@collabora.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Rich Felker <dalias@libc.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
In case CONFIG_XARRAY_MULTI is not defined, xa_store_order can store a
multi-index entry but xas_for_each can't tell sbiling entry from valid
entry. So the check_pause failed when we store a multi-index entry and
wish xas_for_each can handle it normally. Avoid to store multi-index
entry when CONFIG_XARRAY_MULTI is disabled to fix the failure.
Link: https://lkml.kernel.org/r/20250213163659.414309-1-shikemeng@huaweicloud.com
Fixes: c9ba5249ef8b ("Xarray: move forward index correctly in xas_pause()")
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Closes: https://lore.kernel.org/r/CAMuHMdU_bfadUO=0OZ=AoQ9EAmQPA4wsLCBqohXR+QCeCKRn4A@mail.gmail.com
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
The following bug report was found when running a PREEMPT_RT debug kernel.
BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:48
in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 140605, name: kunit_try_catch
preempt_count: 1, expected: 0
Call trace:
rt_spin_lock+0x70/0x140
find_vmap_area+0x84/0x168
find_vm_area+0x1c/0x50
print_address_description.constprop.0+0x2a0/0x320
print_report+0x108/0x1f8
kasan_report+0x90/0xc8
Since commit e30a0361b851 ("kasan: make report_lock a raw spinlock"),
report_lock was changed to raw_spinlock_t to fix another similar
PREEMPT_RT problem. That alone isn't enough to cover other corner cases.
print_address_description() is always invoked under the report_lock. The
context under this lock is always atomic even on PREEMPT_RT.
find_vm_area() acquires vmap_node::busy.lock which is a spinlock_t,
becoming a sleeping lock on PREEMPT_RT and must not be acquired in atomic
context.
Don't invoke find_vm_area() on PREEMPT_RT and just print the address.
Non-PREEMPT_RT builds remain unchanged. Add a DEFINE_WAIT_OVERRIDE_MAP()
macro to tell lockdep that this lock nesting is allowed because the
PREEMPT_RT part (which is invalid) has been taken care of. This macro was
first introduced in commit 0cce06ba859a ("debugobjects,locking: Annotate
debug_object_fill_pool() wait type violation").
Link: https://lkml.kernel.org/r/20250217204402.60533-1-longman@redhat.com
Fixes: e30a0361b851 ("kasan: make report_lock a raw spinlock")
Signed-off-by: Waiman Long <longman@redhat.com>
Suggested-by: Andrey Konovalov <andreyknvl@gmail.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitriy Vyukov <dvyukov@google.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Mariano Pache <npache@redhat.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Updated .mailmap, but forgot these other places.
Link: https://lkml.kernel.org/r/20250212173523.3979840-1-ndesaulniers@google.com
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
When testing if we should try to compact memory or drop caches before we
run the THP or HugeTLB tests we use | as an or operator. This doesn't
work since run_vmtests.sh is written in shell where this is used to pipe
the output of the first argument into the second. Instead use the shell's
-o operator.
Link: https://lkml.kernel.org/r/20250212-kselftest-mm-no-hugepages-v1-1-44702f538522@kernel.org
Fixes: b433ffa8dbac ("selftests: mm: perform some system cleanup before using hugepages")
Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Nico Pache <npache@redhat.com>
Cc: Mariano Pache <npache@redhat.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
When using the HugeTLB kernel command-line to allocate 1G pages from a
specific node, such as:
default_hugepagesz=1G hugepages=1:1
If node 1 happens to not have enough memory for the requested number of 1G
pages, the allocation falls back to other nodes. A quick way to reproduce
this is by creating a KVM guest with a memory-less node and trying to
allocate 1 1G page from it. Instead of failing, the allocation will
fallback to other nodes.
This defeats the purpose of node specific allocation. Also, specific node
allocation for 2M pages don't have this behavior: the allocation will just
fail for the pages it can't satisfy.
This issue happens because HugeTLB calls memblock_alloc_try_nid_raw() for
1G boot-time allocation as this function falls back to other nodes if the
allocation can't be satisfied. Use memblock_alloc_exact_nid_raw()
instead, which ensures that the allocation will only be satisfied from the
specified node.
Link: https://lkml.kernel.org/r/20250211034856.629371-1-luizcap@redhat.com
Fixes: b5389086ad7b ("hugetlbfs: extend the definition of hugepages parameter to support node allocation")
Signed-off-by: Luiz Capitulino <luizcap@redhat.com>
Acked-by: Oscar Salvador <osalvador@suse.de>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: "Mike Rapoport (IBM)" <rppt@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Zhenguo Yao <yaozhenguo1@gmail.com>
Cc: Frank van der Linden <fvdl@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
A softlockup issue was found with stress test:
watchdog: BUG: soft lockup - CPU#27 stuck for 26s! [migration/27:181]
CPU: 27 UID: 0 PID: 181 Comm: migration/27 6.14.0-rc2-next-20250210 #1
Stopper: multi_cpu_stop <- stop_machine_from_inactive_cpu
RIP: 0010:stop_machine_yield+0x2/0x10
RSP: 0000:ff4a0dcecd19be48 EFLAGS: 00000246
RAX: ffffffff89c0108f RBX: ff4a0dcec03afe44 RCX: 0000000000000000
RDX: ff1cdaaf6eba5808 RSI: 0000000000000282 RDI: ff1cda80c1775a40
RBP: 0000000000000001 R08: 00000011620096c6 R09: 7fffffffffffffff
R10: 0000000000000001 R11: 0000000000000100 R12: ff1cda80c1775a40
R13: 0000000000000000 R14: 0000000000000001 R15: ff4a0dcec03afe20
FS: 0000000000000000(0000) GS:ff1cdaaf6eb80000(0000)
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 00000025e2c2a001 CR4: 0000000000773ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
multi_cpu_stop+0x8f/0x100
cpu_stopper_thread+0x90/0x140
smpboot_thread_fn+0xad/0x150
kthread+0xc2/0x100
ret_from_fork+0x2d/0x50
The stress test involves CPU hotplug operations and memory control group
(memcg) operations. The scenario can be described as follows:
echo xx > memory.max cache_ap_online oom_reaper
(CPU23) (CPU50)
xx < usage stop_machine_from_inactive_cpu
for(;;) // all active cpus
trigger OOM queue_stop_cpus_work
// waiting oom_reaper
multi_cpu_stop(migration/xx)
// sync all active cpus ack
// waiting cpu23 ack
// CPU50 loops in multi_cpu_stop
waiting cpu50
Detailed explanation:
1. When the usage is larger than xx, an OOM may be triggered. If the
process does not handle with ths kill signal immediately, it will loop
in the memory_max_write.
2. When cache_ap_online is triggered, the multi_cpu_stop is queued to the
active cpus. Within the multi_cpu_stop function, it attempts to
synchronize the CPU states. However, the CPU23 didn't acknowledge
because it is stuck in a loop within the for(;;).
3. The oom_reaper process is blocked because CPU50 is in a loop, waiting
for CPU23 to acknowledge the synchronization request.
4. Finally, it formed cyclic dependency and lead to softlockup and dead
loop.
To fix this issue, add cond_resched() in the memory_max_write, so that it
will not block migration task.
Link: https://lkml.kernel.org/r/20250211081819.33307-1-chenridong@huaweicloud.com
Fixes: b6e6edcfa405 ("mm: memcontrol: reclaim and OOM kill when shrinking memory.max below usage")
Signed-off-by: Chen Ridong <chenridong@huawei.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Wang Weiyang <wangweiyang2@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Link: https://lkml.kernel.org/r/20250211212117.3195265-1-ndesaulniers@google.com
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
In zap_pte_range(), if the pte lock was released midway, the pte entries
may be refilled with physical pages by another thread, which may cause a
non-empty PTE page to be reclaimed and eventually cause the system to
crash.
To fix it, fall back to the slow path in this case to recheck if all pte
entries are still none.
Link: https://lkml.kernel.org/r/20250211072625.89188-1-zhengqi.arch@bytedance.com
Fixes: 6375e95f381e ("mm: pgtable: reclaim empty PTE page in madvise(MADV_DONTNEED)")
Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
Reported-by: Christian Brauner <brauner@kernel.org>
Closes: https://lore.kernel.org/all/20250207-anbot-bankfilialen-acce9d79a2c7@brauner/
Reported-by: Qu Wenruo <quwenruo.btrfs@gmx.com>
Closes: https://lore.kernel.org/all/152296f3-5c81-4a94-97f3-004108fba7be@gmx.com/
Tested-by: Zi Yan <ziy@nvidia.com>
Cc: <stable@vger.kernel.org>
Cc: "Darrick J. Wong" <djwong@kernel.org>
Cc: Dave Chinner <david@fromorbit.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jann Horn <jannh@google.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
After adding "delay max" and "delay min" to the taskstats structure, the
taskstats version needs to be updated.
Link: https://lkml.kernel.org/r/20250208144901218Q5ptVpqsQkb2MOEmW4Ujn@zte.com.cn
Fixes: f65c64f311ee ("delayacct: add delay min to record delay peak")
Signed-off-by: Wang Yaxin <wang.yaxin@zte.com.cn>
Signed-off-by: Kun Jiang <jiang.kun2@zte.com.cn>
Reviewed-by: xu xin <xu.xin16@zte.com.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
getdelays had a compilation issue because the format string was not
updated when the "delay min" was added. For example, after adding the
"delay min" in printf, there were 7 strings but only 6 "%s" format
specifiers. Similarly, after adding the 't->cpu_delay_total', there were
7 variables but only 6 format characters specifiers, causing compilation
issues as follows. This commit fixes these issues to ensure that
getdelays compiles correctly.
root@xx:~/linux-next/tools/accounting$ make
getdelays.c:199:9: warning: format `%llu' expects argument of type
`long long unsigned int', but argument 8 has type `char *' [-Wformat=]
199 | printf("\n\nCPU %15s%15s%15s%15s%15s%15s\n"
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
.....
216 | "delay total", "delay average", "delay max", "delay min",
| ~~~~~~~~~~~
| |
| char *
getdelays.c:200:21: note: format string is defined here
200 | " %15llu%15llu%15llu%15llu%15.3fms%13.6fms\n"
| ~~~~~^
| |
| long long unsigned int
| %15s
getdelays.c:199:9: warning: format `%f' expects argument of type
`double', but argument 12 has type `long long unsigned int' [-Wformat=]
199 | printf("\n\nCPU %15s%15s%15s%15s%15s%15s\n"
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
.....
220 | (unsigned long long)t->cpu_delay_total,
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
| |
| long long unsigned int
.....
Link: https://lkml.kernel.org/r/20250208144400544RduNRhwIpT3m2JyRBqskZ@zte.com.cn
Fixes: f65c64f311ee ("delayacct: add delay min to record delay peak")
Reviewed-by: xu xin <xu.xin16@zte.com.cn>
Signed-off-by: Wang Yaxin <wang.yaxin@zte.com.cn>
Signed-off-by: Kun Jiang <jiang.kun2@zte.com.cn>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Fan Yu <fan.yu9@zte.com.cn>
Cc: Peilin He <he.peilin@zte.com.cn>
Cc: Qiang Tu <tu.qiang35@zte.com.cn>
Cc: wangyong <wang.yong12@zte.com.cn>
Cc: ye xingchen <ye.xingchen@zte.com.cn>
Cc: Yunkai Zhang <zhang.yunkai@zte.com.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
If migration succeeded, we called
folio_migrate_flags()->mem_cgroup_migrate() to migrate the memcg from the
old to the new folio. This will set memcg_data of the old folio to 0.
Similarly, if migration failed, memcg_data of the dst folio is left unset.
If we call folio_putback_lru() on such folios (memcg_data == 0), we will
add the folio to be freed to the LRU, making memcg code unhappy. Running
the hmm selftests:
# ./hmm-tests
...
# RUN hmm.hmm_device_private.migrate ...
[ 102.078007][T14893] page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x7ff27d200 pfn:0x13cc00
[ 102.079974][T14893] anon flags: 0x17ff00000020018(uptodate|dirty|swapbacked|node=0|zone=2|lastcpupid=0x7ff)
[ 102.082037][T14893] raw: 017ff00000020018 dead000000000100 dead000000000122 ffff8881353896c9
[ 102.083687][T14893] raw: 00000007ff27d200 0000000000000000 00000001ffffffff 0000000000000000
[ 102.085331][T14893] page dumped because: VM_WARN_ON_ONCE_FOLIO(!memcg && !mem_cgroup_disabled())
[ 102.087230][T14893] ------------[ cut here ]------------
[ 102.088279][T14893] WARNING: CPU: 0 PID: 14893 at ./include/linux/memcontrol.h:726 folio_lruvec_lock_irqsave+0x10e/0x170
[ 102.090478][T14893] Modules linked in:
[ 102.091244][T14893] CPU: 0 UID: 0 PID: 14893 Comm: hmm-tests Not tainted 6.13.0-09623-g6c216bc522fd #151
[ 102.093089][T14893] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-2.fc40 04/01/2014
[ 102.094848][T14893] RIP: 0010:folio_lruvec_lock_irqsave+0x10e/0x170
[ 102.096104][T14893] Code: ...
[ 102.099908][T14893] RSP: 0018:ffffc900236c37b0 EFLAGS: 00010293
[ 102.101152][T14893] RAX: 0000000000000000 RBX: ffffea0004f30000 RCX: ffffffff8183f426
[ 102.102684][T14893] RDX: ffff8881063cb880 RSI: ffffffff81b8117f RDI: ffff8881063cb880
[ 102.104227][T14893] RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000
[ 102.105757][T14893] R10: 0000000000000001 R11: 0000000000000002 R12: ffffc900236c37d8
[ 102.107296][T14893] R13: ffff888277a2bcb0 R14: 000000000000001f R15: 0000000000000000
[ 102.108830][T14893] FS: 00007ff27dbdd740(0000) GS:ffff888277a00000(0000) knlGS:0000000000000000
[ 102.110643][T14893] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 102.111924][T14893] CR2: 00007ff27d400000 CR3: 000000010866e000 CR4: 0000000000750ef0
[ 102.113478][T14893] PKRU: 55555554
[ 102.114172][T14893] Call Trace:
[ 102.114805][T14893] <TASK>
[ 102.115397][T14893] ? folio_lruvec_lock_irqsave+0x10e/0x170
[ 102.116547][T14893] ? __warn.cold+0x110/0x210
[ 102.117461][T14893] ? folio_lruvec_lock_irqsave+0x10e/0x170
[ 102.118667][T14893] ? report_bug+0x1b9/0x320
[ 102.119571][T14893] ? handle_bug+0x54/0x90
[ 102.120494][T14893] ? exc_invalid_op+0x17/0x50
[ 102.121433][T14893] ? asm_exc_invalid_op+0x1a/0x20
[ 102.122435][T14893] ? __wake_up_klogd.part.0+0x76/0xd0
[ 102.123506][T14893] ? dump_page+0x4f/0x60
[ 102.124352][T14893] ? folio_lruvec_lock_irqsave+0x10e/0x170
[ 102.125500][T14893] folio_batch_move_lru+0xd4/0x200
[ 102.126577][T14893] ? __pfx_lru_add+0x10/0x10
[ 102.127505][T14893] __folio_batch_add_and_move+0x391/0x720
[ 102.128633][T14893] ? __pfx_lru_add+0x10/0x10
[ 102.129550][T14893] folio_putback_lru+0x16/0x80
[ 102.130564][T14893] migrate_device_finalize+0x9b/0x530
[ 102.131640][T14893] dmirror_migrate_to_device.constprop.0+0x7c5/0xad0
[ 102.133047][T14893] dmirror_fops_unlocked_ioctl+0x89b/0xc80
Likely, nothing else goes wrong: putting the last folio reference will
remove the folio from the LRU again. So besides memcg complaining, adding
the folio to be freed to the LRU is just an unnecessary step.
The new flow resembles what we have in migrate_folio_move(): add the dst
to the lru, remove migration ptes, unlock and unref dst.
Link: https://lkml.kernel.org/r/20250210161317.717936-1-david@redhat.com
Fixes: 8763cb45ab96 ("mm/migrate: new memory migration helper for use with device memory")
Signed-off-by: David Hildenbrand <david@redhat.com>
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
musl-libc warns about the following:
/home/florian/dev/buildroot/output/arm64/rpi4-b/host/aarch64-buildroot-linux-musl/sysroot/usr/include/sys/errno.h:1:2: attention: #warning redirecting incorrect #include <sys/errno.h> to <errno.h> [-Wcpp]
1 | #warning redirecting incorrect #include <sys/errno.h> to <errno.h>
| ^~~~~~~
/home/florian/dev/buildroot/output/arm64/rpi4-b/host/aarch64-buildroot-linux-musl/sysroot/usr/include/sys/fcntl.h:1:2: attention: #warning redirecting incorrect #include <sys/fcntl.h> to <fcntl.h> [-Wcpp]
1 | #warning redirecting incorrect #include <sys/fcntl.h> to <fcntl.h>
| ^~~~~~~
include errno.h and fcntl.h directly.
Link: https://lkml.kernel.org/r/20250210200518.1137295-1-florian.fainelli@broadcom.com
Signed-off-by: Florian Fainelli <florian.fainelli@broadcom.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Map my old business email to personal email.
Link: https://lkml.kernel.org/r/20250205060457.53667-1-feng.tang@linux.alibaba.com
Signed-off-by: Feng Tang <feng.tang@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Map past iterations of my e-mail addresses to the current one.
Link: https://lkml.kernel.org/r/20250205-jjohnson-mailmap-v1-1-269cb7b1710d@oss.qualcomm.com
Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Add a sanity check to madvise_dontneed_free() to address a corner case in
madvise where a race condition causes the current vma being processed to
be backed by a different page size.
During a madvise(MADV_DONTNEED) call on a memory region registered with a
userfaultfd, there's a period of time where the process mm lock is
temporarily released in order to send a UFFD_EVENT_REMOVE and let
userspace handle the event. During this time, the vma covering the
current address range may change due to an explicit mmap done concurrently
by another thread.
If, after that change, the memory region, which was originally backed by
4KB pages, is now backed by hugepages, the end address is rounded down to
a hugepage boundary to avoid data loss (see "Fixes" below). This rounding
may cause the end address to be truncated to the same address as the
start.
Make this corner case follow the same semantics as in other similar cases
where the requested region has zero length (ie. return 0).
This will make madvise_walk_vmas() continue to the next vma in the range
(this time holding the process mm lock) which, due to the prev pointer
becoming stale because of the vma change, will be the same hugepage-backed
vma that was just checked before. The next time madvise_dontneed_free()
runs for this vma, if the start address isn't aligned to a hugepage
boundary, it'll return -EINVAL, which is also in line with the madvise
api.
From userspace perspective, madvise() will return EINVAL because the start
address isn't aligned according to the new vma alignment requirements
(hugepage), even though it was correctly page-aligned when the call was
issued.
Link: https://lkml.kernel.org/r/20250203075206.1452208-1-rcn@igalia.com
Fixes: 8ebe0a5eaaeb ("mm,madvise,hugetlb: fix unexpected data loss with MADV_DONTNEED on hugetlbfs")
Signed-off-by: Ricardo Cañuelo Navarro <rcn@igalia.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Cc: Florent Revest <revest@google.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Commit b7c0ccdfbafd ("mm: zswap: support large folios in zswap_store()")
skips charging any zswap entries when it failed to zswap the entire folio.
However, when some base pages are zswapped but it failed to zswap the
entire folio, the zswap operation is rolled back. When freeing zswap
entries for those pages, zswap_entry_free() uncharges the zswap entries
that were not previously charged, causing zswap charging to become
inconsistent.
This inconsistency triggers two warnings with following steps:
# On a machine with 64GiB of RAM and 36GiB of zswap
$ stress-ng --bigheap 2 # wait until the OOM-killer kills stress-ng
$ sudo reboot
The two warnings are:
in mm/memcontrol.c:163, function obj_cgroup_release():
WARN_ON_ONCE(nr_bytes & (PAGE_SIZE - 1));
in mm/page_counter.c:60, function page_counter_cancel():
if (WARN_ONCE(new < 0, "page_counter underflow: %ld nr_pages=%lu\n",
new, nr_pages))
zswap_stored_pages also becomes inconsistent in the same way.
As suggested by Kanchana, increment zswap_stored_pages and charge zswap
entries within zswap_store_page() when it succeeds. This way,
zswap_entry_free() will decrement the counter and uncharge the entries
when it failed to zswap the entire folio.
While this could potentially be optimized by batching objcg charging and
incrementing the counter, let's focus on fixing the bug this time and
leave the optimization for later after some evaluation.
After resolving the inconsistency, the warnings disappear.
[42.hyeyoo@gmail.com: refactor zswap_store_page()]
Link: https://lkml.kernel.org/r/20250131082037.2426-1-42.hyeyoo@gmail.com
Link: https://lkml.kernel.org/r/20250129100844.2935-1-42.hyeyoo@gmail.com
Fixes: b7c0ccdfbafd ("mm: zswap: support large folios in zswap_store()")
Co-developed-by: Kanchana P Sridhar <kanchana.p.sridhar@intel.com>
Signed-off-by: Kanchana P Sridhar <kanchana.p.sridhar@intel.com>
Signed-off-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Acked-by: Yosry Ahmed <yosry.ahmed@linux.dev>
Acked-by: Nhat Pham <nphamcs@gmail.com>
Cc: Chengming Zhou <chengming.zhou@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
import_iovec() says that it should always be fine to kfree the iovec
returned in @iovp regardless of the error code. __import_iovec_ubuf()
never reallocates it and thus should clear the pointer even in cases when
copy_iovec_*() fail.
Link: https://lkml.kernel.org/r/378ae26923ffc20fd5e41b4360d673bf47b1775b.1738332461.git.asml.silence@gmail.com
Fixes: 3b2deb0e46da ("iov_iter: import single vector iovecs as ITER_UBUF")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christian Brauner <brauner@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Unlock vmcore_mutex when returning -EBUSY.
Link: https://lkml.kernel.org/r/20250129222003.1495713-1-bvanassche@acm.org
Fixes: 0f3b1c40c652 ("fs/proc/vmcore: disallow vmcore modifications while the vmcore is open")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Baoquan he <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
|
|
The pages_touched field represents the number of subbuffers in the ring
buffer that have content that can be read. This is used in accounting of
"dirty_pages" and "buffer_percent" to allow the user to wait for the
buffer to be filled to a certain amount before it reads the buffer in
blocking mode.
The persistent buffer never updated this value so it was set to zero, and
this accounting would take it as it had no content. This would cause user
space to wait for content even though there's enough content in the ring
buffer that satisfies the buffer_percent.
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Vincent Donnefort <vdonnefort@google.com>
Link: https://lore.kernel.org/20250214123512.0631436e@gandalf.local.home
Fixes: 5f3b6e839f3ce ("ring-buffer: Validate boot range memory events")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
When trying to mmap a trace instance buffer that is attached to
reserve_mem, it would crash:
BUG: unable to handle page fault for address: ffffe97bd00025c8
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 2862f3067 P4D 2862f3067 PUD 0
Oops: Oops: 0000 [#1] PREEMPT_RT SMP PTI
CPU: 4 UID: 0 PID: 981 Comm: mmap-rb Not tainted 6.14.0-rc2-test-00003-g7f1a5e3fbf9e-dirty #233
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:validate_page_before_insert+0x5/0xb0
Code: e2 01 89 d0 c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 44 00 00 <48> 8b 46 08 a8 01 75 67 66 90 48 89 f0 8b 50 34 85 d2 74 76 48 89
RSP: 0018:ffffb148c2f3f968 EFLAGS: 00010246
RAX: ffff9fa5d3322000 RBX: ffff9fa5ccff9c08 RCX: 00000000b879ed29
RDX: ffffe97bd00025c0 RSI: ffffe97bd00025c0 RDI: ffff9fa5ccff9c08
RBP: ffffb148c2f3f9f0 R08: 0000000000000004 R09: 0000000000000004
R10: 0000000000000000 R11: 0000000000000200 R12: 0000000000000000
R13: 00007f16a18d5000 R14: ffff9fa5c48db6a8 R15: 0000000000000000
FS: 00007f16a1b54740(0000) GS:ffff9fa73df00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffe97bd00025c8 CR3: 00000001048c6006 CR4: 0000000000172ef0
Call Trace:
<TASK>
? __die_body.cold+0x19/0x1f
? __die+0x2e/0x40
? page_fault_oops+0x157/0x2b0
? search_module_extables+0x53/0x80
? validate_page_before_insert+0x5/0xb0
? kernelmode_fixup_or_oops.isra.0+0x5f/0x70
? __bad_area_nosemaphore+0x16e/0x1b0
? bad_area_nosemaphore+0x16/0x20
? do_kern_addr_fault+0x77/0x90
? exc_page_fault+0x22b/0x230
? asm_exc_page_fault+0x2b/0x30
? validate_page_before_insert+0x5/0xb0
? vm_insert_pages+0x151/0x400
__rb_map_vma+0x21f/0x3f0
ring_buffer_map+0x21b/0x2f0
tracing_buffers_mmap+0x70/0xd0
__mmap_region+0x6f0/0xbd0
mmap_region+0x7f/0x130
do_mmap+0x475/0x610
vm_mmap_pgoff+0xf2/0x1d0
ksys_mmap_pgoff+0x166/0x200
__x64_sys_mmap+0x37/0x50
x64_sys_call+0x1670/0x1d70
do_syscall_64+0xbb/0x1d0
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The reason was that the code that maps the ring buffer pages to user space
has:
page = virt_to_page((void *)cpu_buffer->subbuf_ids[s]);
And uses that in:
vm_insert_pages(vma, vma->vm_start, pages, &nr_pages);
But virt_to_page() does not work with vmap()'d memory which is what the
persistent ring buffer has. It is rather trivial to allow this, but for
now just disable mmap() of instances that have their ring buffer from the
reserve_mem option.
If an mmap() is performed on a persistent buffer it will return -ENODEV
just like it would if the .mmap field wasn't defined in the
file_operations structure.
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Vincent Donnefort <vdonnefort@google.com>
Link: https://lore.kernel.org/20250214115547.0d7287d3@gandalf.local.home
Fixes: 9b7bdf6f6ece6 ("tracing: Have trace_printk not use binary prints if boot buffer")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
Namely: s/becasue/because/ and s/wiht/with/ plus an added article.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
|
|
scripts/Makefile.clang was changed in the linked commit to move --target from
KBUILD_CFLAGS to KBUILD_CPPFLAGS, as that generally has a broader scope.
However that variable is not inspected by the userprogs logic,
breaking cross compilation on clang.
Use both variables to detect bitsize and target arguments for userprogs.
Fixes: feb843a469fb ("kbuild: add $(CLANG_FLAGS) to KBUILD_CPPFLAGS")
Cc: stable@vger.kernel.org
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
|
|
The Tegra210 Audio DMA controller driver did a plain divide:
page_no = (res_page->start - res_base->start) / cdata->ch_base_offset;
which causes problems on 32-bit x86 configurations that have 64-bit
resource sizes:
x86_64-linux-ld: drivers/dma/tegra210-adma.o: in function `tegra_adma_probe':
tegra210-adma.c:(.text+0x1322): undefined reference to `__udivdi3'
because gcc doesn't generate the trivial code for a 64-by-32 divide,
turning it into a function call to do a full 64-by-64 divide. And the
kernel intentionally doesn't provide that helper function, because 99%
of the time all you want is the narrower version.
Of course, tegra210 is a 64-bit architecture and the 32-bit x86 build is
purely for build testing, so this really is just about build coverage
failure.
But build coverage is good.
Side note: div_u64() would be suboptimal if you actually have a 32-bit
resource_t, so our "helper" for divides are admittedly making it harder
than it should be to generate good code for all the possible cases.
At some point, I'll consider 32-bit x86 so entirely legacy that I can't
find it in myself to care any more, and we'll just add the __udivdi3
library function.
But for now, the right thing to do is to use "div_u64()" to show that
you know that you are doing the simpler divide with a 32-bit number.
And the build error enforces that.
While fixing the build issue, also check for division-by-zero, and for
overflow. Which hopefully cannot happen on real production hardware,
but the value of 'ch_base_offset' can definitely be zero in other
places.
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Since commit 5f73e7d0386d ("kbuild: refactor cross-compiling
linux-headers package"), the linux-headers Debian package fails to
build when $(CC) cannot build userspace applications, for example,
when using toolchains installed by the 0day bot.
The host programs in the linux-headers package should be rebuilt using
the disto's cross-compiler, ${DEB_HOST_GNU_TYPE}-gcc instead of $(CC).
Hence, the variable 'CC' must be expanded in this shell script instead
of in the top-level Makefile.
Commit f354fc88a72a ("kbuild: install-extmod-build: add missing
quotation marks for CC variable") was not a correct fix because
CC="ccache gcc" should be unrelated when rebuilding userspace tools.
Fixes: 5f73e7d0386d ("kbuild: refactor cross-compiling linux-headers package")
Reported-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>
Closes: https://lore.kernel.org/linux-kbuild/CAK7LNARb3xO3ptBWOMpwKcyf3=zkfhMey5H2KnB1dOmUwM79dA@mail.gmail.com/T/#t
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Tested-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>
|
|
When CONFIG_OBJTOOL=y or CONFIG_DEBUG_INFO_BTF=y, parallel builds
show awkward "mkdir -p ..." logs.
$ make -j16
[ snip ]
mkdir -p /home/masahiro/ref/linux/tools/objtool && make O=/home/masahiro/ref/linux subdir=tools/objtool --no-print-directory -C objtool
mkdir -p /home/masahiro/ref/linux/tools/bpf/resolve_btfids && make O=/home/masahiro/ref/linux subdir=tools/bpf/resolve_btfids --no-print-directory -C bpf/resolve_btfids
Defining MAKEFLAGS=<value> on the command line wipes out command line
switches from the resultant MAKEFLAGS definition, even though the command
line switches are active. [1]
MAKEFLAGS puts all single-letter options into the first word, and that
word will be empty if no single-letter options were given. [2]
However, this breaks if MAKEFLAGS=<value> is given on the command line.
The tools/ and tools/% targets set MAKEFLAGS=<value> on the command
line, which breaks the following code in tools/scripts/Makefile.include:
short-opts := $(firstword -$(MAKEFLAGS))
If MAKEFLAGS really needs modification, it should be done through the
environment variable, as follows:
MAKEFLAGS=<value> $(MAKE) ...
That said, I question whether modifying MAKEFLAGS is necessary here.
The only flag we might want to exclude is --no-print-directory, as the
tools build system changes the working directory. However, people might
find the "Entering/Leaving directory" logs annoying.
I simply removed the offending MAKEFLAGS=<value>.
[1]: https://savannah.gnu.org/bugs/?62469
[2]: https://www.gnu.org/software/make/manual/make.html#Testing-Flags
Fixes: ea01fa9f63ae ("tools: Connect to the kernel build system")
Fixes: a50e43332756 ("perf tools: Honor parallel jobs")
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Tested-by: Daniel Xu <dxu@dxuuu.xyz>
|
|
Fix issues with enabling SNP host support and effectively SNP support
which is broken with respect to the KVM module being built-in.
SNP host support is enabled in snp_rmptable_init() which is invoked as
device_initcall(). SNP check on IOMMU is done during IOMMU PCI init
(IOMMU_PCI_INIT stage). And for that reason snp_rmptable_init() is
currently invoked via device_initcall() and cannot be invoked via
subsys_initcall() as core IOMMU subsystem gets initialized via
subsys_initcall().
Now, if kvm_amd module is built-in, it gets initialized before SNP host
support is enabled in snp_rmptable_init() :
[ 10.131811] kvm_amd: TSC scaling supported
[ 10.136384] kvm_amd: Nested Virtualization enabled
[ 10.141734] kvm_amd: Nested Paging enabled
[ 10.146304] kvm_amd: LBR virtualization supported
[ 10.151557] kvm_amd: SEV enabled (ASIDs 100 - 509)
[ 10.156905] kvm_amd: SEV-ES enabled (ASIDs 1 - 99)
[ 10.162256] kvm_amd: SEV-SNP enabled (ASIDs 1 - 99)
[ 10.171508] kvm_amd: Virtual VMLOAD VMSAVE supported
[ 10.177052] kvm_amd: Virtual GIF supported
...
...
[ 10.201648] kvm_amd: in svm_enable_virtualization_cpu
And then svm_x86_ops->enable_virtualization_cpu()
(svm_enable_virtualization_cpu) programs MSR_VM_HSAVE_PA as following:
wrmsrl(MSR_VM_HSAVE_PA, sd->save_area_pa);
So VM_HSAVE_PA is non-zero before SNP support is enabled on all CPUs.
snp_rmptable_init() gets invoked after svm_enable_virtualization_cpu()
as following :
...
[ 11.256138] kvm_amd: in svm_enable_virtualization_cpu
...
[ 11.264918] SEV-SNP: in snp_rmptable_init
This triggers a #GP exception in snp_rmptable_init() when snp_enable()
is invoked to set SNP_EN in SYSCFG MSR:
[ 11.294289] unchecked MSR access error: WRMSR to 0xc0010010 (tried to write 0x0000000003fc0000) at rIP: 0xffffffffaf5d5c28 (native_write_msr+0x8/0x30)
...
[ 11.294404] Call Trace:
[ 11.294482] <IRQ>
[ 11.294513] ? show_stack_regs+0x26/0x30
[ 11.294522] ? ex_handler_msr+0x10f/0x180
[ 11.294529] ? search_extable+0x2b/0x40
[ 11.294538] ? fixup_exception+0x2dd/0x340
[ 11.294542] ? exc_general_protection+0x14f/0x440
[ 11.294550] ? asm_exc_general_protection+0x2b/0x30
[ 11.294557] ? __pfx_snp_enable+0x10/0x10
[ 11.294567] ? native_write_msr+0x8/0x30
[ 11.294570] ? __snp_enable+0x5d/0x70
[ 11.294575] snp_enable+0x19/0x20
[ 11.294578] __flush_smp_call_function_queue+0x9c/0x3a0
[ 11.294586] generic_smp_call_function_single_interrupt+0x17/0x20
[ 11.294589] __sysvec_call_function+0x20/0x90
[ 11.294596] sysvec_call_function+0x80/0xb0
[ 11.294601] </IRQ>
[ 11.294603] <TASK>
[ 11.294605] asm_sysvec_call_function+0x1f/0x30
...
[ 11.294631] arch_cpu_idle+0xd/0x20
[ 11.294633] default_idle_call+0x34/0xd0
[ 11.294636] do_idle+0x1f1/0x230
[ 11.294643] ? complete+0x71/0x80
[ 11.294649] cpu_startup_entry+0x30/0x40
[ 11.294652] start_secondary+0x12d/0x160
[ 11.294655] common_startup_64+0x13e/0x141
[ 11.294662] </TASK>
This #GP exception is getting triggered due to the following errata for
AMD family 19h Models 10h-1Fh Processors:
Processor may generate spurious #GP(0) Exception on WRMSR instruction:
Description:
The Processor will generate a spurious #GP(0) Exception on a WRMSR
instruction if the following conditions are all met:
- the target of the WRMSR is a SYSCFG register.
- the write changes the value of SYSCFG.SNPEn from 0 to 1.
- One of the threads that share the physical core has a non-zero
value in the VM_HSAVE_PA MSR.
The document being referred to above:
https://www.amd.com/content/dam/amd/en/documents/processor-tech-docs/revision-guides/57095-PUB_1_01.pdf
To summarize, with kvm_amd module being built-in, KVM/SVM initialization
happens before host SNP is enabled and this SVM initialization
sets VM_HSAVE_PA to non-zero, which then triggers a #GP when
SYSCFG.SNPEn is being set and this will subsequently cause
SNP_INIT(_EX) to fail with INVALID_CONFIG error as SYSCFG[SnpEn] is not
set on all CPUs.
Essentially SNP host enabling code should be invoked before KVM
initialization, which is currently not the case when KVM is built-in.
Add fix to call snp_rmptable_init() early from iommu_snp_enable()
directly and not invoked via device_initcall() which enables SNP host
support before KVM initialization with kvm_amd module built-in.
Add additional handling for `iommu=off` or `amd_iommu=off` options.
Note that IOMMUs need to be enabled for SNP initialization, therefore,
if host SNP support is enabled but late IOMMU initialization fails
then that will cause PSP driver's SNP_INIT to fail as IOMMU SNP sanity
checks in SNP firmware will fail with invalid configuration error as
below:
[ 9.723114] ccp 0000:23:00.1: sev enabled
[ 9.727602] ccp 0000:23:00.1: psp enabled
[ 9.732527] ccp 0000:a2:00.1: enabling device (0000 -> 0002)
[ 9.739098] ccp 0000:a2:00.1: no command queues available
[ 9.745167] ccp 0000:a2:00.1: psp enabled
[ 9.805337] ccp 0000:23:00.1: SEV-SNP: failed to INIT rc -5, error 0x3
[ 9.866426] ccp 0000:23:00.1: SEV API:1.53 build:5
Fixes: c3b86e61b756 ("x86/cpufeatures: Enable/unmask SEV-SNP CPU feature")
Co-developed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Co-developed-by: Vasant Hegde <vasant.hegde@amd.com>
Signed-off-by: Vasant Hegde <vasant.hegde@amd.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Ashish Kalra <ashish.kalra@amd.com>
Acked-by: Joerg Roedel <jroedel@suse.de>
Message-ID: <138b520fb83964782303b43ade4369cd181fdd9c.1739226950.git.ashish.kalra@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
|
|
The kernel's initcall infrastructure lacks the ability to express
dependencies between initcalls, whereas the modules infrastructure
automatically handles dependencies via symbol loading. Ensure the
PSP SEV driver is initialized before proceeding in sev_hardware_setup()
if KVM is built-in as the dependency isn't handled by the initcall
infrastructure.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Ashish Kalra <ashish.kalra@amd.com>
Message-ID: <f78ddb64087df27e7bcb1ae0ab53f55aa0804fab.1739226950.git.ashish.kalra@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
|
|
KVM is dependent on the PSP SEV driver and PSP SEV driver needs to be
loaded before KVM module. In case of module loading any dependent
modules are automatically loaded but in case of built-in modules there
is no inherent mechanism available to specify dependencies between
modules and ensure that any dependent modules are loaded implicitly.
Add a new external API interface for PSP module initialization which
allows PSP SEV driver to be loaded explicitly if KVM is built-in.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Co-developed-by: Ashish Kalra <ashish.kalra@amd.com>
Signed-off-by: Ashish Kalra <ashish.kalra@amd.com>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Message-ID: <15279ca0cad56a07cf12834ec544310f85ff5edc.1739226950.git.ashish.kalra@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
|
|
Remove hard-coded strings by using the str_yes_no() helper function.
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Signed-off-by: Matt Turner <mattst88@gmail.com>
|
|
Replace the deprecated one-element array with a modern flexible array
member in the struct crb_struct.
Reviewed-by: Kees Cook <kees@kernel.org>
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Signed-off-by: Matt Turner <mattst88@gmail.com>
|
|
do_page_fault() and do_entUna() are special because they use
non-standard stack frame layout. Fix them manually.
Cc: stable@vger.kernel.org
Tested-by: Maciej W. Rozycki <macro@orcam.me.uk>
Tested-by: Magnus Lindholm <linmag7@gmail.com>
Tested-by: Matt Turner <mattst88@gmail.com>
Reviewed-by: Maciej W. Rozycki <macro@orcam.me.uk>
Suggested-by: Maciej W. Rozycki <macro@orcam.me.uk>
Signed-off-by: Ivan Kokshaysky <ink@unseen.parts>
Signed-off-by: Matt Turner <mattst88@gmail.com>
|
|
The problem is that GCC expects 16-byte alignment of the incoming stack
since early 2004, as Maciej found out [1]:
Having actually dug speculatively I can see that the psABI was changed in
GCC 3.5 with commit e5e10fb4a350 ("re PR target/14539 (128-bit long double
improperly aligned)") back in Mar 2004, when the stack pointer alignment
was increased from 8 bytes to 16 bytes, and arch/alpha/kernel/entry.S has
various suspicious stack pointer adjustments, starting with SP_OFF which
is not a whole multiple of 16.
Also, as Magnus noted, "ALPHA Calling Standard" [2] required the same:
D.3.1 Stack Alignment
This standard requires that stacks be octaword aligned at the time a
new procedure is invoked.
However:
- the "normal" kernel stack is always misaligned by 8 bytes, thanks to
the odd number of 64-bit words in 'struct pt_regs', which is the very
first thing pushed onto the kernel thread stack;
- syscall, fault, interrupt etc. handlers may, or may not, receive aligned
stack depending on numerous factors.
Somehow we got away with it until recently, when we ended up with
a stack corruption in kernel/smp.c:smp_call_function_single() due to
its use of 32-byte aligned local data and the compiler doing clever
things allocating it on the stack.
This adds padding between the PAL-saved and kernel-saved registers
so that 'struct pt_regs' have an even number of 64-bit words.
This makes the stack properly aligned for most of the kernel
code, except two handlers which need special threatment.
Note: struct pt_regs doesn't belong in uapi/asm; this should be fixed,
but let's put this off until later.
Link: https://lore.kernel.org/rcu/alpine.DEB.2.21.2501130248010.18889@angie.orcam.me.uk/ [1]
Link: https://bitsavers.org/pdf/dec/alpha/Alpha_Calling_Standard_Rev_2.0_19900427.pdf [2]
Cc: stable@vger.kernel.org
Tested-by: Maciej W. Rozycki <macro@orcam.me.uk>
Tested-by: Magnus Lindholm <linmag7@gmail.com>
Tested-by: Matt Turner <mattst88@gmail.com>
Reviewed-by: Maciej W. Rozycki <macro@orcam.me.uk>
Signed-off-by: Ivan Kokshaysky <ink@unseen.parts>
Signed-off-by: Matt Turner <mattst88@gmail.com>
|
|
This allows the assembly in entry.S to automatically keep in sync with
changes in the stack layout (struct pt_regs and struct switch_stack).
Cc: stable@vger.kernel.org
Tested-by: Maciej W. Rozycki <macro@orcam.me.uk>
Tested-by: Matt Turner <mattst88@gmail.com>
Reviewed-by: Maciej W. Rozycki <macro@orcam.me.uk>
Signed-off-by: Ivan Kokshaysky <ink@unseen.parts>
Signed-off-by: Matt Turner <mattst88@gmail.com>
|
|
The meta data for a mapped ring buffer contains an array of indexes of all
the subbuffers. The first entry is the reader page, and the rest of the
entries lay out the order of the subbuffers in how the ring buffer link
list is to be created.
The validator currently makes sure that all the entries are within the
range of 0 and nr_subbufs. But it does not check if there are any
duplicates.
While working on the ring buffer, I corrupted this array, where I added
duplicates. The validator did not catch it and created the ring buffer
link list on top of it. Luckily, the corruption was only that the reader
page was also in the writer path and only presented corrupted data but did
not crash the kernel. But if there were duplicates in the writer side,
then it could corrupt the ring buffer link list and cause a crash.
Create a bitmask array with the size of the number of subbuffers. Then
clear it. When walking through the subbuf array checking to see if the
entries are within the range, test if its bit is already set in the
subbuf_mask. If it is, then there is duplicates and fail the validation.
If not, set the corresponding bit and continue.
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Vincent Donnefort <vdonnefort@google.com>
Link: https://lore.kernel.org/20250214102820.7509ddea@gandalf.local.home
Fixes: c76883f18e59b ("ring-buffer: Add test if range of boot buffer is valid")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
Currently if __tracing_resize_ring_buffer() returns an error, the
tracing_resize_ringbuffer() returns -ENOMEM. But it may not be a memory
issue that caused the function to fail. If the ring buffer is memory
mapped, then the resizing of the ring buffer will be disabled. But if the
user tries to resize the buffer, it will get an -ENOMEM returned, which is
confusing because there is plenty of memory. The actual error returned was
-EBUSY, which would make much more sense to the user.
Cc: stable@vger.kernel.org
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Vincent Donnefort <vdonnefort@google.com>
Link: https://lore.kernel.org/20250213134132.7e4505d7@gandalf.local.home
Fixes: 117c39200d9d7 ("ring-buffer: Introducing ring-buffer mapping functions")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
|
|
Memory mapping the tracing ring buffer will disable resizing the buffer.
But if there's an error in the memory mapping like an invalid parameter,
the function exits out without re-enabling the resizing of the ring
buffer, preventing the ring buffer from being resized after that.
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Vincent Donnefort <vdonnefort@google.com>
Link: https://lore.kernel.org/20250213131957.530ec3c5@gandalf.local.home
Fixes: 117c39200d9d7 ("ring-buffer: Introducing ring-buffer mapping functions")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
Kemeng Shi
Lorenzo Stoakes
Ge Yang
gao xu
Sebastian Andrzej Siewior
Ujwal Kundur
Ma Wupeng
Qi Zheng
Haoxiang Li
SeongJae Park
John Hubbard
Waiman Long
Nick Desaulniers
Mark Brown
Luiz Capitulino
Chen Ridong
Wang Yaxin
David Hildenbrand
Florian Fainelli
Feng Tang
Jeff Johnson
Ricardo Cañuelo Navarro
Hyeonggon Yoo
Pavel Begunkov
Bart Van Assche
Linus Torvalds
Steven Rostedt
Uwe Kleine-König
Thomas Weißschuh
Masahiro Yamada
Ashish Kalra
Sean Christopherson
Thorsten Blum
Ivan Kokshaysky