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>.
Possible dependencies:
fac35ba763ed ("mm/hugetlb: fix races when looking up a CONT-PTE/PMD size hugetlb page")
ad1ac596e8a8 ("mm/migration: fix potential pte_unmap on an not mapped pte")
4dd845b5a3e5 ("mm/swapops: rework swap entry manipulation code")
af5cdaf82238 ("mm: remove special swap entry functions")
b3807a91aca7 ("mm: page_vma_mapped_walk(): add a level of indentation")
e2e1d4076c77 ("mm: page_vma_mapped_walk(): prettify PVMW_MIGRATION block")
3306d3119cea ("mm: page_vma_mapped_walk(): use pmde for *pvmw->pmd")
f003c03bd29e ("mm: page_vma_mapped_walk(): use page for pvmw->page")
494334e43c16 ("mm/thp: fix vma_address() if virtual address below file offset")
732ed55823fc ("mm/thp: try_to_unmap() use TTU_SYNC for safe splitting")
99fa8a48203d ("mm/thp: fix __split_huge_pmd_locked() on shmem migration entry")
ffc90cbb2970 ("mm, thp: use head page in __migration_entry_wait()")
a44f89dc6c5f ("mm/huge_memory.c: use helper function migration_entry_to_page()")
374437a274e2 ("mm/pgtable-generic.c: optimize the VM_BUG_ON condition in pmdp_huge_clear_flush()")
c045c72ccde3 ("mm/pgtable-generic.c: simplify the VM_BUG_ON condition in pmdp_huge_clear_flush()")
013339df116c ("mm/rmap: always do TTU_IGNORE_ACCESS")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From fac35ba763ed07ba93154c95ffc0c4a55023707f Mon Sep 17 00:00:00 2001
From: Baolin Wang <baolin.wang(a)linux.alibaba.com>
Date: Thu, 1 Sep 2022 18:41:31 +0800
Subject: [PATCH] mm/hugetlb: fix races when looking up a CONT-PTE/PMD size
hugetlb page
On some architectures (like ARM64), it can support CONT-PTE/PMD size
hugetlb, which means it can support not only PMD/PUD size hugetlb (2M and
1G), but also CONT-PTE/PMD size(64K and 32M) if a 4K page size specified.
So when looking up a CONT-PTE size hugetlb page by follow_page(), it will
use pte_offset_map_lock() to get the pte entry lock for the CONT-PTE size
hugetlb in follow_page_pte(). However this pte entry lock is incorrect
for the CONT-PTE size hugetlb, since we should use huge_pte_lock() to get
the correct lock, which is mm->page_table_lock.
That means the pte entry of the CONT-PTE size hugetlb under current pte
lock is unstable in follow_page_pte(), we can continue to migrate or
poison the pte entry of the CONT-PTE size hugetlb, which can cause some
potential race issues, even though they are under the 'pte lock'.
For example, suppose thread A is trying to look up a CONT-PTE size hugetlb
page by move_pages() syscall under the lock, however antoher thread B can
migrate the CONT-PTE hugetlb page at the same time, which will cause
thread A to get an incorrect page, if thread A also wants to do page
migration, then data inconsistency error occurs.
Moreover we have the same issue for CONT-PMD size hugetlb in
follow_huge_pmd().
To fix above issues, rename the follow_huge_pmd() as follow_huge_pmd_pte()
to handle PMD and PTE level size hugetlb, which uses huge_pte_lock() to
get the correct pte entry lock to make the pte entry stable.
Mike said:
Support for CONT_PMD/_PTE was added with bb9dd3df8ee9 ("arm64: hugetlb:
refactor find_num_contig()"). Patch series "Support for contiguous pte
hugepages", v4. However, I do not believe these code paths were
executed until migration support was added with 5480280d3f2d ("arm64/mm:
enable HugeTLB migration for contiguous bit HugeTLB pages") I would go
with 5480280d3f2d for the Fixes: targe.
Link: https://lkml.kernel.org/r/635f43bdd85ac2615a58405da82b4d33c6e5eb05.16620175…
Fixes: 5480280d3f2d ("arm64/mm: enable HugeTLB migration for contiguous bit HugeTLB pages")
Signed-off-by: Baolin Wang <baolin.wang(a)linux.alibaba.com>
Suggested-by: Mike Kravetz <mike.kravetz(a)oracle.com>
Reviewed-by: Mike Kravetz <mike.kravetz(a)oracle.com>
Cc: David Hildenbrand <david(a)redhat.com>
Cc: Muchun Song <songmuchun(a)bytedance.com>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index 3ec981a0d8b3..67c88b82fc32 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -207,8 +207,8 @@ struct page *follow_huge_addr(struct mm_struct *mm, unsigned long address,
struct page *follow_huge_pd(struct vm_area_struct *vma,
unsigned long address, hugepd_t hpd,
int flags, int pdshift);
-struct page *follow_huge_pmd(struct mm_struct *mm, unsigned long address,
- pmd_t *pmd, int flags);
+struct page *follow_huge_pmd_pte(struct vm_area_struct *vma, unsigned long address,
+ int flags);
struct page *follow_huge_pud(struct mm_struct *mm, unsigned long address,
pud_t *pud, int flags);
struct page *follow_huge_pgd(struct mm_struct *mm, unsigned long address,
@@ -312,8 +312,8 @@ static inline struct page *follow_huge_pd(struct vm_area_struct *vma,
return NULL;
}
-static inline struct page *follow_huge_pmd(struct mm_struct *mm,
- unsigned long address, pmd_t *pmd, int flags)
+static inline struct page *follow_huge_pmd_pte(struct vm_area_struct *vma,
+ unsigned long address, int flags)
{
return NULL;
}
diff --git a/mm/gup.c b/mm/gup.c
index 00926abb4426..251cb6a10bc0 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -530,6 +530,18 @@ static struct page *follow_page_pte(struct vm_area_struct *vma,
if (WARN_ON_ONCE((flags & (FOLL_PIN | FOLL_GET)) ==
(FOLL_PIN | FOLL_GET)))
return ERR_PTR(-EINVAL);
+
+ /*
+ * Considering PTE level hugetlb, like continuous-PTE hugetlb on
+ * ARM64 architecture.
+ */
+ if (is_vm_hugetlb_page(vma)) {
+ page = follow_huge_pmd_pte(vma, address, flags);
+ if (page)
+ return page;
+ return no_page_table(vma, flags);
+ }
+
retry:
if (unlikely(pmd_bad(*pmd)))
return no_page_table(vma, flags);
@@ -662,7 +674,7 @@ static struct page *follow_pmd_mask(struct vm_area_struct *vma,
if (pmd_none(pmdval))
return no_page_table(vma, flags);
if (pmd_huge(pmdval) && is_vm_hugetlb_page(vma)) {
- page = follow_huge_pmd(mm, address, pmd, flags);
+ page = follow_huge_pmd_pte(vma, address, flags);
if (page)
return page;
return no_page_table(vma, flags);
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 0bdfc7e1c933..9564bf817e6a 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -6946,12 +6946,13 @@ follow_huge_pd(struct vm_area_struct *vma,
}
struct page * __weak
-follow_huge_pmd(struct mm_struct *mm, unsigned long address,
- pmd_t *pmd, int flags)
+follow_huge_pmd_pte(struct vm_area_struct *vma, unsigned long address, int flags)
{
+ struct hstate *h = hstate_vma(vma);
+ struct mm_struct *mm = vma->vm_mm;
struct page *page = NULL;
spinlock_t *ptl;
- pte_t pte;
+ pte_t *ptep, pte;
/*
* FOLL_PIN is not supported for follow_page(). Ordinary GUP goes via
@@ -6961,17 +6962,15 @@ follow_huge_pmd(struct mm_struct *mm, unsigned long address,
return NULL;
retry:
- ptl = pmd_lockptr(mm, pmd);
- spin_lock(ptl);
- /*
- * make sure that the address range covered by this pmd is not
- * unmapped from other threads.
- */
- if (!pmd_huge(*pmd))
- goto out;
- pte = huge_ptep_get((pte_t *)pmd);
+ ptep = huge_pte_offset(mm, address, huge_page_size(h));
+ if (!ptep)
+ return NULL;
+
+ ptl = huge_pte_lock(h, mm, ptep);
+ pte = huge_ptep_get(ptep);
if (pte_present(pte)) {
- page = pmd_page(*pmd) + ((address & ~PMD_MASK) >> PAGE_SHIFT);
+ page = pte_page(pte) +
+ ((address & ~huge_page_mask(h)) >> PAGE_SHIFT);
/*
* try_grab_page() should always succeed here, because: a) we
* hold the pmd (ptl) lock, and b) we've just checked that the
@@ -6987,7 +6986,7 @@ follow_huge_pmd(struct mm_struct *mm, unsigned long address,
} else {
if (is_hugetlb_entry_migration(pte)) {
spin_unlock(ptl);
- __migration_entry_wait_huge((pte_t *)pmd, ptl);
+ __migration_entry_wait_huge(ptep, ptl);
goto retry;
}
/*
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>.
Possible dependencies:
fac35ba763ed ("mm/hugetlb: fix races when looking up a CONT-PTE/PMD size hugetlb page")
ad1ac596e8a8 ("mm/migration: fix potential pte_unmap on an not mapped pte")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From fac35ba763ed07ba93154c95ffc0c4a55023707f Mon Sep 17 00:00:00 2001
From: Baolin Wang <baolin.wang(a)linux.alibaba.com>
Date: Thu, 1 Sep 2022 18:41:31 +0800
Subject: [PATCH] mm/hugetlb: fix races when looking up a CONT-PTE/PMD size
hugetlb page
On some architectures (like ARM64), it can support CONT-PTE/PMD size
hugetlb, which means it can support not only PMD/PUD size hugetlb (2M and
1G), but also CONT-PTE/PMD size(64K and 32M) if a 4K page size specified.
So when looking up a CONT-PTE size hugetlb page by follow_page(), it will
use pte_offset_map_lock() to get the pte entry lock for the CONT-PTE size
hugetlb in follow_page_pte(). However this pte entry lock is incorrect
for the CONT-PTE size hugetlb, since we should use huge_pte_lock() to get
the correct lock, which is mm->page_table_lock.
That means the pte entry of the CONT-PTE size hugetlb under current pte
lock is unstable in follow_page_pte(), we can continue to migrate or
poison the pte entry of the CONT-PTE size hugetlb, which can cause some
potential race issues, even though they are under the 'pte lock'.
For example, suppose thread A is trying to look up a CONT-PTE size hugetlb
page by move_pages() syscall under the lock, however antoher thread B can
migrate the CONT-PTE hugetlb page at the same time, which will cause
thread A to get an incorrect page, if thread A also wants to do page
migration, then data inconsistency error occurs.
Moreover we have the same issue for CONT-PMD size hugetlb in
follow_huge_pmd().
To fix above issues, rename the follow_huge_pmd() as follow_huge_pmd_pte()
to handle PMD and PTE level size hugetlb, which uses huge_pte_lock() to
get the correct pte entry lock to make the pte entry stable.
Mike said:
Support for CONT_PMD/_PTE was added with bb9dd3df8ee9 ("arm64: hugetlb:
refactor find_num_contig()"). Patch series "Support for contiguous pte
hugepages", v4. However, I do not believe these code paths were
executed until migration support was added with 5480280d3f2d ("arm64/mm:
enable HugeTLB migration for contiguous bit HugeTLB pages") I would go
with 5480280d3f2d for the Fixes: targe.
Link: https://lkml.kernel.org/r/635f43bdd85ac2615a58405da82b4d33c6e5eb05.16620175…
Fixes: 5480280d3f2d ("arm64/mm: enable HugeTLB migration for contiguous bit HugeTLB pages")
Signed-off-by: Baolin Wang <baolin.wang(a)linux.alibaba.com>
Suggested-by: Mike Kravetz <mike.kravetz(a)oracle.com>
Reviewed-by: Mike Kravetz <mike.kravetz(a)oracle.com>
Cc: David Hildenbrand <david(a)redhat.com>
Cc: Muchun Song <songmuchun(a)bytedance.com>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index 3ec981a0d8b3..67c88b82fc32 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -207,8 +207,8 @@ struct page *follow_huge_addr(struct mm_struct *mm, unsigned long address,
struct page *follow_huge_pd(struct vm_area_struct *vma,
unsigned long address, hugepd_t hpd,
int flags, int pdshift);
-struct page *follow_huge_pmd(struct mm_struct *mm, unsigned long address,
- pmd_t *pmd, int flags);
+struct page *follow_huge_pmd_pte(struct vm_area_struct *vma, unsigned long address,
+ int flags);
struct page *follow_huge_pud(struct mm_struct *mm, unsigned long address,
pud_t *pud, int flags);
struct page *follow_huge_pgd(struct mm_struct *mm, unsigned long address,
@@ -312,8 +312,8 @@ static inline struct page *follow_huge_pd(struct vm_area_struct *vma,
return NULL;
}
-static inline struct page *follow_huge_pmd(struct mm_struct *mm,
- unsigned long address, pmd_t *pmd, int flags)
+static inline struct page *follow_huge_pmd_pte(struct vm_area_struct *vma,
+ unsigned long address, int flags)
{
return NULL;
}
diff --git a/mm/gup.c b/mm/gup.c
index 00926abb4426..251cb6a10bc0 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -530,6 +530,18 @@ static struct page *follow_page_pte(struct vm_area_struct *vma,
if (WARN_ON_ONCE((flags & (FOLL_PIN | FOLL_GET)) ==
(FOLL_PIN | FOLL_GET)))
return ERR_PTR(-EINVAL);
+
+ /*
+ * Considering PTE level hugetlb, like continuous-PTE hugetlb on
+ * ARM64 architecture.
+ */
+ if (is_vm_hugetlb_page(vma)) {
+ page = follow_huge_pmd_pte(vma, address, flags);
+ if (page)
+ return page;
+ return no_page_table(vma, flags);
+ }
+
retry:
if (unlikely(pmd_bad(*pmd)))
return no_page_table(vma, flags);
@@ -662,7 +674,7 @@ static struct page *follow_pmd_mask(struct vm_area_struct *vma,
if (pmd_none(pmdval))
return no_page_table(vma, flags);
if (pmd_huge(pmdval) && is_vm_hugetlb_page(vma)) {
- page = follow_huge_pmd(mm, address, pmd, flags);
+ page = follow_huge_pmd_pte(vma, address, flags);
if (page)
return page;
return no_page_table(vma, flags);
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 0bdfc7e1c933..9564bf817e6a 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -6946,12 +6946,13 @@ follow_huge_pd(struct vm_area_struct *vma,
}
struct page * __weak
-follow_huge_pmd(struct mm_struct *mm, unsigned long address,
- pmd_t *pmd, int flags)
+follow_huge_pmd_pte(struct vm_area_struct *vma, unsigned long address, int flags)
{
+ struct hstate *h = hstate_vma(vma);
+ struct mm_struct *mm = vma->vm_mm;
struct page *page = NULL;
spinlock_t *ptl;
- pte_t pte;
+ pte_t *ptep, pte;
/*
* FOLL_PIN is not supported for follow_page(). Ordinary GUP goes via
@@ -6961,17 +6962,15 @@ follow_huge_pmd(struct mm_struct *mm, unsigned long address,
return NULL;
retry:
- ptl = pmd_lockptr(mm, pmd);
- spin_lock(ptl);
- /*
- * make sure that the address range covered by this pmd is not
- * unmapped from other threads.
- */
- if (!pmd_huge(*pmd))
- goto out;
- pte = huge_ptep_get((pte_t *)pmd);
+ ptep = huge_pte_offset(mm, address, huge_page_size(h));
+ if (!ptep)
+ return NULL;
+
+ ptl = huge_pte_lock(h, mm, ptep);
+ pte = huge_ptep_get(ptep);
if (pte_present(pte)) {
- page = pmd_page(*pmd) + ((address & ~PMD_MASK) >> PAGE_SHIFT);
+ page = pte_page(pte) +
+ ((address & ~huge_page_mask(h)) >> PAGE_SHIFT);
/*
* try_grab_page() should always succeed here, because: a) we
* hold the pmd (ptl) lock, and b) we've just checked that the
@@ -6987,7 +6986,7 @@ follow_huge_pmd(struct mm_struct *mm, unsigned long address,
} else {
if (is_hugetlb_entry_migration(pte)) {
spin_unlock(ptl);
- __migration_entry_wait_huge((pte_t *)pmd, ptl);
+ __migration_entry_wait_huge(ptep, ptl);
goto retry;
}
/*
From: Jeffle Xu <jefflexu(a)linux.alibaba.com>
[ Upstream commit b0d97557ebfc9d5ba5f2939339a9fdd267abafeb ]
The inflight of partition 0 doesn't include inflight IOs to all
sub-partitions, since currently mq calculates inflight of specific
partition by simply camparing the value of the partition pointer.
Thus the following case is possible:
$ cat /sys/block/vda/inflight
0 0
$ cat /sys/block/vda/vda1/inflight
0 128
While single queue device (on a previous version, e.g. v3.10) has no
this issue:
$cat /sys/block/sda/sda3/inflight
0 33
$cat /sys/block/sda/inflight
0 33
Partition 0 should be specially handled since it represents the whole
disk. This issue is introduced since commit bf0ddaba65dd ("blk-mq: fix
sysfs inflight counter").
Besides, this patch can also fix the inflight statistics of part 0 in
/proc/diskstats. Before this patch, the inflight statistics of part 0
doesn't include that of sub partitions. (I have marked the 'inflight'
field with asterisk.)
$cat /proc/diskstats
259 0 nvme0n1 45974469 0 367814768 6445794 1 0 1 0 *0* 111062 6445794 0 0 0 0 0 0
259 2 nvme0n1p1 45974058 0 367797952 6445727 0 0 0 0 *33* 111001 6445727 0 0 0 0 0 0
This is introduced since commit f299b7c7a9de ("blk-mq: provide internal
in-flight variant").
Fixes: bf0ddaba65dd ("blk-mq: fix sysfs inflight counter")
Fixes: f299b7c7a9de ("blk-mq: provide internal in-flight variant")
Signed-off-by: Jeffle Xu <jefflexu(a)linux.alibaba.com>
Reviewed-by: Christoph Hellwig <hch(a)lst.de>
[axboe: adapt for 5.11 partition change]
Signed-off-by: Jens Axboe <axboe(a)kernel.dk>
[khazhy: adapt for 5.10 partition]
Signed-off-by: Khazhismel Kumykov <khazhy(a)google.com>
---
block/blk-mq.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/block/blk-mq.c b/block/blk-mq.c
index cfc039fabf8c..e37ba792902a 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -105,7 +105,8 @@ static bool blk_mq_check_inflight(struct blk_mq_hw_ctx *hctx,
{
struct mq_inflight *mi = priv;
- if (rq->part == mi->part && blk_mq_rq_state(rq) == MQ_RQ_IN_FLIGHT)
+ if ((!mi->part->partno || rq->part == mi->part) &&
+ blk_mq_rq_state(rq) == MQ_RQ_IN_FLIGHT)
mi->inflight[rq_data_dir(rq)]++;
return true;
--
2.38.0.rc1.362.ged0d419d3c-goog
The patch below does not apply to the 4.9-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
Possible dependencies:
171df58028bf ("arm64: errata: Add Cortex-A55 to the repeat tlbi list")
39fdb65f52e9 ("arm64: errata: Add Cortex-A510 to the repeat tlbi list")
1dd498e5e26a ("KVM: arm64: Workaround Cortex-A510's single-step and PAC trap errata")
297ae1eb23b0 ("arm64: cpufeature: List early Cortex-A510 parts as having broken dbm")
708e8af4924e ("arm64: errata: Add detection for TRBE trace data corruption")
3bd94a8759de ("arm64: errata: Add detection for TRBE invalid prohibited states")
607a9afaae09 ("arm64: errata: Add detection for TRBE ignored system register writes")
83bb2c1a01d7 ("KVM: arm64: Save PSTATE early on exit")
d7e0a795bf37 ("Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 171df58028bf4649460fb146a56a58dcb0c8f75a Mon Sep 17 00:00:00 2001
From: James Morse <james.morse(a)arm.com>
Date: Fri, 30 Sep 2022 14:19:59 +0100
Subject: [PATCH] arm64: errata: Add Cortex-A55 to the repeat tlbi list
Cortex-A55 is affected by an erratum where in rare circumstances the
CPUs may not handle a race between a break-before-make sequence on one
CPU, and another CPU accessing the same page. This could allow a store
to a page that has been unmapped.
Work around this by adding the affected CPUs to the list that needs
TLB sequences to be done twice.
Signed-off-by: James Morse <james.morse(a)arm.com>
Cc: <stable(a)vger.kernel.org>
Link: https://lore.kernel.org/r/20220930131959.3082594-1-james.morse@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas(a)arm.com>
diff --git a/Documentation/arm64/silicon-errata.rst b/Documentation/arm64/silicon-errata.rst
index 17d9fc5d14fb..808ade4cc008 100644
--- a/Documentation/arm64/silicon-errata.rst
+++ b/Documentation/arm64/silicon-errata.rst
@@ -76,6 +76,8 @@ stable kernels.
+----------------+-----------------+-----------------+-----------------------------+
| ARM | Cortex-A55 | #1530923 | ARM64_ERRATUM_1530923 |
+----------------+-----------------+-----------------+-----------------------------+
+| ARM | Cortex-A55 | #2441007 | ARM64_ERRATUM_2441007 |
++----------------+-----------------+-----------------+-----------------------------+
| ARM | Cortex-A57 | #832075 | ARM64_ERRATUM_832075 |
+----------------+-----------------+-----------------+-----------------------------+
| ARM | Cortex-A57 | #852523 | N/A |
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 1675310f1791..20d082d54bd8 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -634,6 +634,23 @@ config ARM64_ERRATUM_1530923
config ARM64_WORKAROUND_REPEAT_TLBI
bool
+config ARM64_ERRATUM_2441007
+ bool "Cortex-A55: Completion of affected memory accesses might not be guaranteed by completion of a TLBI"
+ default y
+ select ARM64_WORKAROUND_REPEAT_TLBI
+ help
+ This option adds a workaround for ARM Cortex-A55 erratum #2441007.
+
+ Under very rare circumstances, affected Cortex-A55 CPUs
+ may not handle a race between a break-before-make sequence on one
+ CPU, and another CPU accessing the same page. This could allow a
+ store to a page that has been unmapped.
+
+ Work around this by adding the affected CPUs to the list that needs
+ TLB sequences to be done twice.
+
+ If unsure, say Y.
+
config ARM64_ERRATUM_1286807
bool "Cortex-A76: Modification of the translation table for a virtual address might lead to read-after-read ordering violation"
default y
diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c
index 58ca4f6b25d6..89ac00084f38 100644
--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c
@@ -230,6 +230,11 @@ static const struct arm64_cpu_capabilities arm64_repeat_tlbi_list[] = {
ERRATA_MIDR_RANGE(MIDR_QCOM_KRYO_4XX_GOLD, 0xc, 0xe, 0xf, 0xe),
},
#endif
+#ifdef CONFIG_ARM64_ERRATUM_2441007
+ {
+ ERRATA_MIDR_ALL_VERSIONS(MIDR_CORTEX_A55),
+ },
+#endif
#ifdef CONFIG_ARM64_ERRATUM_2441009
{
/* Cortex-A510 r0p0 -> r1p1. Fixed in r1p2 */
The patch below does not apply to the 4.14-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
Possible dependencies:
171df58028bf ("arm64: errata: Add Cortex-A55 to the repeat tlbi list")
39fdb65f52e9 ("arm64: errata: Add Cortex-A510 to the repeat tlbi list")
1dd498e5e26a ("KVM: arm64: Workaround Cortex-A510's single-step and PAC trap errata")
297ae1eb23b0 ("arm64: cpufeature: List early Cortex-A510 parts as having broken dbm")
708e8af4924e ("arm64: errata: Add detection for TRBE trace data corruption")
3bd94a8759de ("arm64: errata: Add detection for TRBE invalid prohibited states")
607a9afaae09 ("arm64: errata: Add detection for TRBE ignored system register writes")
83bb2c1a01d7 ("KVM: arm64: Save PSTATE early on exit")
d7e0a795bf37 ("Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 171df58028bf4649460fb146a56a58dcb0c8f75a Mon Sep 17 00:00:00 2001
From: James Morse <james.morse(a)arm.com>
Date: Fri, 30 Sep 2022 14:19:59 +0100
Subject: [PATCH] arm64: errata: Add Cortex-A55 to the repeat tlbi list
Cortex-A55 is affected by an erratum where in rare circumstances the
CPUs may not handle a race between a break-before-make sequence on one
CPU, and another CPU accessing the same page. This could allow a store
to a page that has been unmapped.
Work around this by adding the affected CPUs to the list that needs
TLB sequences to be done twice.
Signed-off-by: James Morse <james.morse(a)arm.com>
Cc: <stable(a)vger.kernel.org>
Link: https://lore.kernel.org/r/20220930131959.3082594-1-james.morse@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas(a)arm.com>
diff --git a/Documentation/arm64/silicon-errata.rst b/Documentation/arm64/silicon-errata.rst
index 17d9fc5d14fb..808ade4cc008 100644
--- a/Documentation/arm64/silicon-errata.rst
+++ b/Documentation/arm64/silicon-errata.rst
@@ -76,6 +76,8 @@ stable kernels.
+----------------+-----------------+-----------------+-----------------------------+
| ARM | Cortex-A55 | #1530923 | ARM64_ERRATUM_1530923 |
+----------------+-----------------+-----------------+-----------------------------+
+| ARM | Cortex-A55 | #2441007 | ARM64_ERRATUM_2441007 |
++----------------+-----------------+-----------------+-----------------------------+
| ARM | Cortex-A57 | #832075 | ARM64_ERRATUM_832075 |
+----------------+-----------------+-----------------+-----------------------------+
| ARM | Cortex-A57 | #852523 | N/A |
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 1675310f1791..20d082d54bd8 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -634,6 +634,23 @@ config ARM64_ERRATUM_1530923
config ARM64_WORKAROUND_REPEAT_TLBI
bool
+config ARM64_ERRATUM_2441007
+ bool "Cortex-A55: Completion of affected memory accesses might not be guaranteed by completion of a TLBI"
+ default y
+ select ARM64_WORKAROUND_REPEAT_TLBI
+ help
+ This option adds a workaround for ARM Cortex-A55 erratum #2441007.
+
+ Under very rare circumstances, affected Cortex-A55 CPUs
+ may not handle a race between a break-before-make sequence on one
+ CPU, and another CPU accessing the same page. This could allow a
+ store to a page that has been unmapped.
+
+ Work around this by adding the affected CPUs to the list that needs
+ TLB sequences to be done twice.
+
+ If unsure, say Y.
+
config ARM64_ERRATUM_1286807
bool "Cortex-A76: Modification of the translation table for a virtual address might lead to read-after-read ordering violation"
default y
diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c
index 58ca4f6b25d6..89ac00084f38 100644
--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c
@@ -230,6 +230,11 @@ static const struct arm64_cpu_capabilities arm64_repeat_tlbi_list[] = {
ERRATA_MIDR_RANGE(MIDR_QCOM_KRYO_4XX_GOLD, 0xc, 0xe, 0xf, 0xe),
},
#endif
+#ifdef CONFIG_ARM64_ERRATUM_2441007
+ {
+ ERRATA_MIDR_ALL_VERSIONS(MIDR_CORTEX_A55),
+ },
+#endif
#ifdef CONFIG_ARM64_ERRATUM_2441009
{
/* Cortex-A510 r0p0 -> r1p1. Fixed in r1p2 */
The patch below does not apply to the 4.19-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>.
Possible dependencies:
171df58028bf ("arm64: errata: Add Cortex-A55 to the repeat tlbi list")
39fdb65f52e9 ("arm64: errata: Add Cortex-A510 to the repeat tlbi list")
1dd498e5e26a ("KVM: arm64: Workaround Cortex-A510's single-step and PAC trap errata")
297ae1eb23b0 ("arm64: cpufeature: List early Cortex-A510 parts as having broken dbm")
708e8af4924e ("arm64: errata: Add detection for TRBE trace data corruption")
3bd94a8759de ("arm64: errata: Add detection for TRBE invalid prohibited states")
607a9afaae09 ("arm64: errata: Add detection for TRBE ignored system register writes")
83bb2c1a01d7 ("KVM: arm64: Save PSTATE early on exit")
d7e0a795bf37 ("Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 171df58028bf4649460fb146a56a58dcb0c8f75a Mon Sep 17 00:00:00 2001
From: James Morse <james.morse(a)arm.com>
Date: Fri, 30 Sep 2022 14:19:59 +0100
Subject: [PATCH] arm64: errata: Add Cortex-A55 to the repeat tlbi list
Cortex-A55 is affected by an erratum where in rare circumstances the
CPUs may not handle a race between a break-before-make sequence on one
CPU, and another CPU accessing the same page. This could allow a store
to a page that has been unmapped.
Work around this by adding the affected CPUs to the list that needs
TLB sequences to be done twice.
Signed-off-by: James Morse <james.morse(a)arm.com>
Cc: <stable(a)vger.kernel.org>
Link: https://lore.kernel.org/r/20220930131959.3082594-1-james.morse@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas(a)arm.com>
diff --git a/Documentation/arm64/silicon-errata.rst b/Documentation/arm64/silicon-errata.rst
index 17d9fc5d14fb..808ade4cc008 100644
--- a/Documentation/arm64/silicon-errata.rst
+++ b/Documentation/arm64/silicon-errata.rst
@@ -76,6 +76,8 @@ stable kernels.
+----------------+-----------------+-----------------+-----------------------------+
| ARM | Cortex-A55 | #1530923 | ARM64_ERRATUM_1530923 |
+----------------+-----------------+-----------------+-----------------------------+
+| ARM | Cortex-A55 | #2441007 | ARM64_ERRATUM_2441007 |
++----------------+-----------------+-----------------+-----------------------------+
| ARM | Cortex-A57 | #832075 | ARM64_ERRATUM_832075 |
+----------------+-----------------+-----------------+-----------------------------+
| ARM | Cortex-A57 | #852523 | N/A |
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 1675310f1791..20d082d54bd8 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -634,6 +634,23 @@ config ARM64_ERRATUM_1530923
config ARM64_WORKAROUND_REPEAT_TLBI
bool
+config ARM64_ERRATUM_2441007
+ bool "Cortex-A55: Completion of affected memory accesses might not be guaranteed by completion of a TLBI"
+ default y
+ select ARM64_WORKAROUND_REPEAT_TLBI
+ help
+ This option adds a workaround for ARM Cortex-A55 erratum #2441007.
+
+ Under very rare circumstances, affected Cortex-A55 CPUs
+ may not handle a race between a break-before-make sequence on one
+ CPU, and another CPU accessing the same page. This could allow a
+ store to a page that has been unmapped.
+
+ Work around this by adding the affected CPUs to the list that needs
+ TLB sequences to be done twice.
+
+ If unsure, say Y.
+
config ARM64_ERRATUM_1286807
bool "Cortex-A76: Modification of the translation table for a virtual address might lead to read-after-read ordering violation"
default y
diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c
index 58ca4f6b25d6..89ac00084f38 100644
--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c
@@ -230,6 +230,11 @@ static const struct arm64_cpu_capabilities arm64_repeat_tlbi_list[] = {
ERRATA_MIDR_RANGE(MIDR_QCOM_KRYO_4XX_GOLD, 0xc, 0xe, 0xf, 0xe),
},
#endif
+#ifdef CONFIG_ARM64_ERRATUM_2441007
+ {
+ ERRATA_MIDR_ALL_VERSIONS(MIDR_CORTEX_A55),
+ },
+#endif
#ifdef CONFIG_ARM64_ERRATUM_2441009
{
/* Cortex-A510 r0p0 -> r1p1. Fixed in r1p2 */
The patch below does not apply to the 5.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
Possible dependencies:
171df58028bf ("arm64: errata: Add Cortex-A55 to the repeat tlbi list")
39fdb65f52e9 ("arm64: errata: Add Cortex-A510 to the repeat tlbi list")
1dd498e5e26a ("KVM: arm64: Workaround Cortex-A510's single-step and PAC trap errata")
297ae1eb23b0 ("arm64: cpufeature: List early Cortex-A510 parts as having broken dbm")
708e8af4924e ("arm64: errata: Add detection for TRBE trace data corruption")
3bd94a8759de ("arm64: errata: Add detection for TRBE invalid prohibited states")
607a9afaae09 ("arm64: errata: Add detection for TRBE ignored system register writes")
83bb2c1a01d7 ("KVM: arm64: Save PSTATE early on exit")
d7e0a795bf37 ("Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 171df58028bf4649460fb146a56a58dcb0c8f75a Mon Sep 17 00:00:00 2001
From: James Morse <james.morse(a)arm.com>
Date: Fri, 30 Sep 2022 14:19:59 +0100
Subject: [PATCH] arm64: errata: Add Cortex-A55 to the repeat tlbi list
Cortex-A55 is affected by an erratum where in rare circumstances the
CPUs may not handle a race between a break-before-make sequence on one
CPU, and another CPU accessing the same page. This could allow a store
to a page that has been unmapped.
Work around this by adding the affected CPUs to the list that needs
TLB sequences to be done twice.
Signed-off-by: James Morse <james.morse(a)arm.com>
Cc: <stable(a)vger.kernel.org>
Link: https://lore.kernel.org/r/20220930131959.3082594-1-james.morse@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas(a)arm.com>
diff --git a/Documentation/arm64/silicon-errata.rst b/Documentation/arm64/silicon-errata.rst
index 17d9fc5d14fb..808ade4cc008 100644
--- a/Documentation/arm64/silicon-errata.rst
+++ b/Documentation/arm64/silicon-errata.rst
@@ -76,6 +76,8 @@ stable kernels.
+----------------+-----------------+-----------------+-----------------------------+
| ARM | Cortex-A55 | #1530923 | ARM64_ERRATUM_1530923 |
+----------------+-----------------+-----------------+-----------------------------+
+| ARM | Cortex-A55 | #2441007 | ARM64_ERRATUM_2441007 |
++----------------+-----------------+-----------------+-----------------------------+
| ARM | Cortex-A57 | #832075 | ARM64_ERRATUM_832075 |
+----------------+-----------------+-----------------+-----------------------------+
| ARM | Cortex-A57 | #852523 | N/A |
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 1675310f1791..20d082d54bd8 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -634,6 +634,23 @@ config ARM64_ERRATUM_1530923
config ARM64_WORKAROUND_REPEAT_TLBI
bool
+config ARM64_ERRATUM_2441007
+ bool "Cortex-A55: Completion of affected memory accesses might not be guaranteed by completion of a TLBI"
+ default y
+ select ARM64_WORKAROUND_REPEAT_TLBI
+ help
+ This option adds a workaround for ARM Cortex-A55 erratum #2441007.
+
+ Under very rare circumstances, affected Cortex-A55 CPUs
+ may not handle a race between a break-before-make sequence on one
+ CPU, and another CPU accessing the same page. This could allow a
+ store to a page that has been unmapped.
+
+ Work around this by adding the affected CPUs to the list that needs
+ TLB sequences to be done twice.
+
+ If unsure, say Y.
+
config ARM64_ERRATUM_1286807
bool "Cortex-A76: Modification of the translation table for a virtual address might lead to read-after-read ordering violation"
default y
diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c
index 58ca4f6b25d6..89ac00084f38 100644
--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c
@@ -230,6 +230,11 @@ static const struct arm64_cpu_capabilities arm64_repeat_tlbi_list[] = {
ERRATA_MIDR_RANGE(MIDR_QCOM_KRYO_4XX_GOLD, 0xc, 0xe, 0xf, 0xe),
},
#endif
+#ifdef CONFIG_ARM64_ERRATUM_2441007
+ {
+ ERRATA_MIDR_ALL_VERSIONS(MIDR_CORTEX_A55),
+ },
+#endif
#ifdef CONFIG_ARM64_ERRATUM_2441009
{
/* Cortex-A510 r0p0 -> r1p1. Fixed in r1p2 */
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>.
Possible dependencies:
171df58028bf ("arm64: errata: Add Cortex-A55 to the repeat tlbi list")
39fdb65f52e9 ("arm64: errata: Add Cortex-A510 to the repeat tlbi list")
1dd498e5e26a ("KVM: arm64: Workaround Cortex-A510's single-step and PAC trap errata")
297ae1eb23b0 ("arm64: cpufeature: List early Cortex-A510 parts as having broken dbm")
708e8af4924e ("arm64: errata: Add detection for TRBE trace data corruption")
3bd94a8759de ("arm64: errata: Add detection for TRBE invalid prohibited states")
607a9afaae09 ("arm64: errata: Add detection for TRBE ignored system register writes")
83bb2c1a01d7 ("KVM: arm64: Save PSTATE early on exit")
d7e0a795bf37 ("Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 171df58028bf4649460fb146a56a58dcb0c8f75a Mon Sep 17 00:00:00 2001
From: James Morse <james.morse(a)arm.com>
Date: Fri, 30 Sep 2022 14:19:59 +0100
Subject: [PATCH] arm64: errata: Add Cortex-A55 to the repeat tlbi list
Cortex-A55 is affected by an erratum where in rare circumstances the
CPUs may not handle a race between a break-before-make sequence on one
CPU, and another CPU accessing the same page. This could allow a store
to a page that has been unmapped.
Work around this by adding the affected CPUs to the list that needs
TLB sequences to be done twice.
Signed-off-by: James Morse <james.morse(a)arm.com>
Cc: <stable(a)vger.kernel.org>
Link: https://lore.kernel.org/r/20220930131959.3082594-1-james.morse@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas(a)arm.com>
diff --git a/Documentation/arm64/silicon-errata.rst b/Documentation/arm64/silicon-errata.rst
index 17d9fc5d14fb..808ade4cc008 100644
--- a/Documentation/arm64/silicon-errata.rst
+++ b/Documentation/arm64/silicon-errata.rst
@@ -76,6 +76,8 @@ stable kernels.
+----------------+-----------------+-----------------+-----------------------------+
| ARM | Cortex-A55 | #1530923 | ARM64_ERRATUM_1530923 |
+----------------+-----------------+-----------------+-----------------------------+
+| ARM | Cortex-A55 | #2441007 | ARM64_ERRATUM_2441007 |
++----------------+-----------------+-----------------+-----------------------------+
| ARM | Cortex-A57 | #832075 | ARM64_ERRATUM_832075 |
+----------------+-----------------+-----------------+-----------------------------+
| ARM | Cortex-A57 | #852523 | N/A |
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 1675310f1791..20d082d54bd8 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -634,6 +634,23 @@ config ARM64_ERRATUM_1530923
config ARM64_WORKAROUND_REPEAT_TLBI
bool
+config ARM64_ERRATUM_2441007
+ bool "Cortex-A55: Completion of affected memory accesses might not be guaranteed by completion of a TLBI"
+ default y
+ select ARM64_WORKAROUND_REPEAT_TLBI
+ help
+ This option adds a workaround for ARM Cortex-A55 erratum #2441007.
+
+ Under very rare circumstances, affected Cortex-A55 CPUs
+ may not handle a race between a break-before-make sequence on one
+ CPU, and another CPU accessing the same page. This could allow a
+ store to a page that has been unmapped.
+
+ Work around this by adding the affected CPUs to the list that needs
+ TLB sequences to be done twice.
+
+ If unsure, say Y.
+
config ARM64_ERRATUM_1286807
bool "Cortex-A76: Modification of the translation table for a virtual address might lead to read-after-read ordering violation"
default y
diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c
index 58ca4f6b25d6..89ac00084f38 100644
--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c
@@ -230,6 +230,11 @@ static const struct arm64_cpu_capabilities arm64_repeat_tlbi_list[] = {
ERRATA_MIDR_RANGE(MIDR_QCOM_KRYO_4XX_GOLD, 0xc, 0xe, 0xf, 0xe),
},
#endif
+#ifdef CONFIG_ARM64_ERRATUM_2441007
+ {
+ ERRATA_MIDR_ALL_VERSIONS(MIDR_CORTEX_A55),
+ },
+#endif
#ifdef CONFIG_ARM64_ERRATUM_2441009
{
/* Cortex-A510 r0p0 -> r1p1. Fixed in r1p2 */
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>.
Possible dependencies:
a8e5e5146ad0 ("arm64: mte: Avoid setting PG_mte_tagged if no tags cleared or restored")
20794545c146 ("arm64: kasan: Revert "arm64: mte: reset the page tag in page->flags"")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From a8e5e5146ad08d794c58252bab00b261045ef16d Mon Sep 17 00:00:00 2001
From: Catalin Marinas <catalin.marinas(a)arm.com>
Date: Thu, 6 Oct 2022 17:33:54 +0100
Subject: [PATCH] arm64: mte: Avoid setting PG_mte_tagged if no tags cleared or
restored
Prior to commit 69e3b846d8a7 ("arm64: mte: Sync tags for pages where PTE
is untagged"), mte_sync_tags() was only called for pte_tagged() entries
(those mapped with PROT_MTE). Therefore mte_sync_tags() could safely use
test_and_set_bit(PG_mte_tagged, &page->flags) without inadvertently
setting PG_mte_tagged on an untagged page.
The above commit was required as guests may enable MTE without any
control at the stage 2 mapping, nor a PROT_MTE mapping in the VMM.
However, the side-effect was that any page with a PTE that looked like
swap (or migration) was getting PG_mte_tagged set automatically. A
subsequent page copy (e.g. migration) copied the tags to the destination
page even if the tags were owned by KASAN.
This issue was masked by the page_kasan_tag_reset() call introduced in
commit e5b8d9218951 ("arm64: mte: reset the page tag in page->flags").
When this commit was reverted (20794545c146), KASAN started reporting
access faults because the overriding tags in a page did not match the
original page->flags (with CONFIG_KASAN_HW_TAGS=y):
BUG: KASAN: invalid-access in copy_page+0x10/0xd0 arch/arm64/lib/copy_page.S:26
Read at addr f5ff000017f2e000 by task syz-executor.1/2218
Pointer tag: [f5], memory tag: [f2]
Move the PG_mte_tagged bit setting from mte_sync_tags() to the actual
place where tags are cleared (mte_sync_page_tags()) or restored
(mte_restore_tags()).
Signed-off-by: Catalin Marinas <catalin.marinas(a)arm.com>
Reported-by: syzbot+c2c79c6d6eddc5262b77(a)syzkaller.appspotmail.com
Fixes: 69e3b846d8a7 ("arm64: mte: Sync tags for pages where PTE is untagged")
Cc: <stable(a)vger.kernel.org> # 5.14.x
Cc: Steven Price <steven.price(a)arm.com>
Cc: Andrey Konovalov <andreyknvl(a)gmail.com>
Cc: Vincenzo Frascino <vincenzo.frascino(a)arm.com>
Cc: Will Deacon <will(a)kernel.org>
Link: https://lore.kernel.org/r/0000000000004387dc05e5888ae5@google.com/
Reviewed-by: Steven Price <steven.price(a)arm.com>
Link: https://lore.kernel.org/r/20221006163354.3194102-1-catalin.marinas@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas(a)arm.com>
diff --git a/arch/arm64/kernel/mte.c b/arch/arm64/kernel/mte.c
index aca88470fb69..7467217c1eaf 100644
--- a/arch/arm64/kernel/mte.c
+++ b/arch/arm64/kernel/mte.c
@@ -48,7 +48,12 @@ static void mte_sync_page_tags(struct page *page, pte_t old_pte,
if (!pte_is_tagged)
return;
- mte_clear_page_tags(page_address(page));
+ /*
+ * Test PG_mte_tagged again in case it was racing with another
+ * set_pte_at().
+ */
+ if (!test_and_set_bit(PG_mte_tagged, &page->flags))
+ mte_clear_page_tags(page_address(page));
}
void mte_sync_tags(pte_t old_pte, pte_t pte)
@@ -64,7 +69,7 @@ void mte_sync_tags(pte_t old_pte, pte_t pte)
/* if PG_mte_tagged is set, tags have already been initialised */
for (i = 0; i < nr_pages; i++, page++) {
- if (!test_and_set_bit(PG_mte_tagged, &page->flags))
+ if (!test_bit(PG_mte_tagged, &page->flags))
mte_sync_page_tags(page, old_pte, check_swap,
pte_is_tagged);
}
diff --git a/arch/arm64/mm/mteswap.c b/arch/arm64/mm/mteswap.c
index 4334dec93bd4..bed803d8e158 100644
--- a/arch/arm64/mm/mteswap.c
+++ b/arch/arm64/mm/mteswap.c
@@ -53,7 +53,12 @@ bool mte_restore_tags(swp_entry_t entry, struct page *page)
if (!tags)
return false;
- mte_restore_page_tags(page_address(page), tags);
+ /*
+ * Test PG_mte_tagged again in case it was racing with another
+ * set_pte_at().
+ */
+ if (!test_and_set_bit(PG_mte_tagged, &page->flags))
+ mte_restore_page_tags(page_address(page), tags);
return true;
}
The patch below does not apply to the 5.19-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>.
Possible dependencies:
a8e5e5146ad0 ("arm64: mte: Avoid setting PG_mte_tagged if no tags cleared or restored")
20794545c146 ("arm64: kasan: Revert "arm64: mte: reset the page tag in page->flags"")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From a8e5e5146ad08d794c58252bab00b261045ef16d Mon Sep 17 00:00:00 2001
From: Catalin Marinas <catalin.marinas(a)arm.com>
Date: Thu, 6 Oct 2022 17:33:54 +0100
Subject: [PATCH] arm64: mte: Avoid setting PG_mte_tagged if no tags cleared or
restored
Prior to commit 69e3b846d8a7 ("arm64: mte: Sync tags for pages where PTE
is untagged"), mte_sync_tags() was only called for pte_tagged() entries
(those mapped with PROT_MTE). Therefore mte_sync_tags() could safely use
test_and_set_bit(PG_mte_tagged, &page->flags) without inadvertently
setting PG_mte_tagged on an untagged page.
The above commit was required as guests may enable MTE without any
control at the stage 2 mapping, nor a PROT_MTE mapping in the VMM.
However, the side-effect was that any page with a PTE that looked like
swap (or migration) was getting PG_mte_tagged set automatically. A
subsequent page copy (e.g. migration) copied the tags to the destination
page even if the tags were owned by KASAN.
This issue was masked by the page_kasan_tag_reset() call introduced in
commit e5b8d9218951 ("arm64: mte: reset the page tag in page->flags").
When this commit was reverted (20794545c146), KASAN started reporting
access faults because the overriding tags in a page did not match the
original page->flags (with CONFIG_KASAN_HW_TAGS=y):
BUG: KASAN: invalid-access in copy_page+0x10/0xd0 arch/arm64/lib/copy_page.S:26
Read at addr f5ff000017f2e000 by task syz-executor.1/2218
Pointer tag: [f5], memory tag: [f2]
Move the PG_mte_tagged bit setting from mte_sync_tags() to the actual
place where tags are cleared (mte_sync_page_tags()) or restored
(mte_restore_tags()).
Signed-off-by: Catalin Marinas <catalin.marinas(a)arm.com>
Reported-by: syzbot+c2c79c6d6eddc5262b77(a)syzkaller.appspotmail.com
Fixes: 69e3b846d8a7 ("arm64: mte: Sync tags for pages where PTE is untagged")
Cc: <stable(a)vger.kernel.org> # 5.14.x
Cc: Steven Price <steven.price(a)arm.com>
Cc: Andrey Konovalov <andreyknvl(a)gmail.com>
Cc: Vincenzo Frascino <vincenzo.frascino(a)arm.com>
Cc: Will Deacon <will(a)kernel.org>
Link: https://lore.kernel.org/r/0000000000004387dc05e5888ae5@google.com/
Reviewed-by: Steven Price <steven.price(a)arm.com>
Link: https://lore.kernel.org/r/20221006163354.3194102-1-catalin.marinas@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas(a)arm.com>
diff --git a/arch/arm64/kernel/mte.c b/arch/arm64/kernel/mte.c
index aca88470fb69..7467217c1eaf 100644
--- a/arch/arm64/kernel/mte.c
+++ b/arch/arm64/kernel/mte.c
@@ -48,7 +48,12 @@ static void mte_sync_page_tags(struct page *page, pte_t old_pte,
if (!pte_is_tagged)
return;
- mte_clear_page_tags(page_address(page));
+ /*
+ * Test PG_mte_tagged again in case it was racing with another
+ * set_pte_at().
+ */
+ if (!test_and_set_bit(PG_mte_tagged, &page->flags))
+ mte_clear_page_tags(page_address(page));
}
void mte_sync_tags(pte_t old_pte, pte_t pte)
@@ -64,7 +69,7 @@ void mte_sync_tags(pte_t old_pte, pte_t pte)
/* if PG_mte_tagged is set, tags have already been initialised */
for (i = 0; i < nr_pages; i++, page++) {
- if (!test_and_set_bit(PG_mte_tagged, &page->flags))
+ if (!test_bit(PG_mte_tagged, &page->flags))
mte_sync_page_tags(page, old_pte, check_swap,
pte_is_tagged);
}
diff --git a/arch/arm64/mm/mteswap.c b/arch/arm64/mm/mteswap.c
index 4334dec93bd4..bed803d8e158 100644
--- a/arch/arm64/mm/mteswap.c
+++ b/arch/arm64/mm/mteswap.c
@@ -53,7 +53,12 @@ bool mte_restore_tags(swp_entry_t entry, struct page *page)
if (!tags)
return false;
- mte_restore_page_tags(page_address(page), tags);
+ /*
+ * Test PG_mte_tagged again in case it was racing with another
+ * set_pte_at().
+ */
+ if (!test_and_set_bit(PG_mte_tagged, &page->flags))
+ mte_restore_page_tags(page_address(page), tags);
return true;
}