The patch below does not apply to the v6.11-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
Thanks,
Sasha
------------------ original commit in Linus's tree ------------------
From 9d08ec41a0645283d79a2e642205d488feaceacf Mon Sep 17 00:00:00 2001
From: Yu Zhao <yuzhao(a)google.com>
Date: Sat, 19 Oct 2024 22:22:12 -0600
Subject: [PATCH] mm: allow set/clear page_type again
Some page flags (page->flags) were converted to page types
(page->page_types). A recent example is PG_hugetlb.
From the exclusive writer's perspective, e.g., a thread doing
__folio_set_hugetlb(), there is a difference between the page flag and
type APIs: the former allows the same non-atomic operation to be repeated
whereas the latter does not. For example, calling __folio_set_hugetlb()
twice triggers VM_BUG_ON_FOLIO(), since the second call expects the type
(PG_hugetlb) not to be set previously.
Using add_hugetlb_folio() as an example, it calls __folio_set_hugetlb() in
the following error-handling path. And when that happens, it triggers the
aforementioned VM_BUG_ON_FOLIO().
if (folio_test_hugetlb(folio)) {
rc = hugetlb_vmemmap_restore_folio(h, folio);
if (rc) {
spin_lock_irq(&hugetlb_lock);
add_hugetlb_folio(h, folio, false);
...
It is possible to make hugeTLB comply with the new requirements from the
page type API. However, a straightforward fix would be to just allow the
same page type to be set or cleared again inside the API, to avoid any
changes to its callers.
Link: https://lkml.kernel.org/r/20241020042212.296781-1-yuzhao@google.com
Fixes: d99e3140a4d3 ("mm: turn folio_test_hugetlb into a PageType")
Signed-off-by: Yu Zhao <yuzhao(a)google.com>
Cc: Matthew Wilcox (Oracle) <willy(a)infradead.org>
Cc: Muchun Song <muchun.song(a)linux.dev>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
include/linux/page-flags.h | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h
index 1b3a767104878..cc839e4365c18 100644
--- a/include/linux/page-flags.h
+++ b/include/linux/page-flags.h
@@ -975,12 +975,16 @@ static __always_inline bool folio_test_##fname(const struct folio *folio) \
} \
static __always_inline void __folio_set_##fname(struct folio *folio) \
{ \
+ if (folio_test_##fname(folio)) \
+ return; \
VM_BUG_ON_FOLIO(data_race(folio->page.page_type) != UINT_MAX, \
folio); \
folio->page.page_type = (unsigned int)PGTY_##lname << 24; \
} \
static __always_inline void __folio_clear_##fname(struct folio *folio) \
{ \
+ if (folio->page.page_type == UINT_MAX) \
+ return; \
VM_BUG_ON_FOLIO(!folio_test_##fname(folio), folio); \
folio->page.page_type = UINT_MAX; \
}
@@ -993,11 +997,15 @@ static __always_inline int Page##uname(const struct page *page) \
} \
static __always_inline void __SetPage##uname(struct page *page) \
{ \
+ if (Page##uname(page)) \
+ return; \
VM_BUG_ON_PAGE(data_race(page->page_type) != UINT_MAX, page); \
page->page_type = (unsigned int)PGTY_##lname << 24; \
} \
static __always_inline void __ClearPage##uname(struct page *page) \
{ \
+ if (page->page_type == UINT_MAX) \
+ return; \
VM_BUG_ON_PAGE(!Page##uname(page), page); \
page->page_type = UINT_MAX; \
}
--
2.43.0
The patch below does not apply to the v6.11-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
Thanks,
Sasha
------------------ original commit in Linus's tree ------------------
From 01626a18230246efdcea322aa8f067e60ffe5ccd Mon Sep 17 00:00:00 2001
From: Barry Song <v-songbaohua(a)oppo.com>
Date: Fri, 27 Sep 2024 09:19:36 +1200
Subject: [PATCH] mm: avoid unconditional one-tick sleep when swapcache_prepare
fails
Commit 13ddaf26be32 ("mm/swap: fix race when skipping swapcache")
introduced an unconditional one-tick sleep when `swapcache_prepare()`
fails, which has led to reports of UI stuttering on latency-sensitive
Android devices. To address this, we can use a waitqueue to wake up tasks
that fail `swapcache_prepare()` sooner, instead of always sleeping for a
full tick. While tasks may occasionally be woken by an unrelated
`do_swap_page()`, this method is preferable to two scenarios: rapid
re-entry into page faults, which can cause livelocks, and multiple
millisecond sleeps, which visibly degrade user experience.
Oven's testing shows that a single waitqueue resolves the UI stuttering
issue. If a 'thundering herd' problem becomes apparent later, a waitqueue
hash similar to `folio_wait_table[PAGE_WAIT_TABLE_SIZE]` for page bit
locks can be introduced.
[v-songbaohua(a)oppo.com: wake_up only when swapcache_wq waitqueue is active]
Link: https://lkml.kernel.org/r/20241008130807.40833-1-21cnbao@gmail.com
Link: https://lkml.kernel.org/r/20240926211936.75373-1-21cnbao@gmail.com
Fixes: 13ddaf26be32 ("mm/swap: fix race when skipping swapcache")
Signed-off-by: Barry Song <v-songbaohua(a)oppo.com>
Reported-by: Oven Liyang <liyangouwen1(a)oppo.com>
Tested-by: Oven Liyang <liyangouwen1(a)oppo.com>
Cc: Kairui Song <kasong(a)tencent.com>
Cc: "Huang, Ying" <ying.huang(a)intel.com>
Cc: Yu Zhao <yuzhao(a)google.com>
Cc: David Hildenbrand <david(a)redhat.com>
Cc: Chris Li <chrisl(a)kernel.org>
Cc: Hugh Dickins <hughd(a)google.com>
Cc: Johannes Weiner <hannes(a)cmpxchg.org>
Cc: Matthew Wilcox (Oracle) <willy(a)infradead.org>
Cc: Michal Hocko <mhocko(a)suse.com>
Cc: Minchan Kim <minchan(a)kernel.org>
Cc: Yosry Ahmed <yosryahmed(a)google.com>
Cc: SeongJae Park <sj(a)kernel.org>
Cc: Kalesh Singh <kaleshsingh(a)google.com>
Cc: Suren Baghdasaryan <surenb(a)google.com>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
mm/memory.c | 15 +++++++++++++--
1 file changed, 13 insertions(+), 2 deletions(-)
diff --git a/mm/memory.c b/mm/memory.c
index 3ccee51adfbbd..bdf77a3ec47bc 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -4187,6 +4187,8 @@ static struct folio *alloc_swap_folio(struct vm_fault *vmf)
}
#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
+static DECLARE_WAIT_QUEUE_HEAD(swapcache_wq);
+
/*
* We enter with non-exclusive mmap_lock (to exclude vma changes,
* but allow concurrent faults), and pte mapped but not yet locked.
@@ -4199,6 +4201,7 @@ vm_fault_t do_swap_page(struct vm_fault *vmf)
{
struct vm_area_struct *vma = vmf->vma;
struct folio *swapcache, *folio = NULL;
+ DECLARE_WAITQUEUE(wait, current);
struct page *page;
struct swap_info_struct *si = NULL;
rmap_t rmap_flags = RMAP_NONE;
@@ -4297,7 +4300,9 @@ vm_fault_t do_swap_page(struct vm_fault *vmf)
* Relax a bit to prevent rapid
* repeated page faults.
*/
+ add_wait_queue(&swapcache_wq, &wait);
schedule_timeout_uninterruptible(1);
+ remove_wait_queue(&swapcache_wq, &wait);
goto out_page;
}
need_clear_cache = true;
@@ -4604,8 +4609,11 @@ vm_fault_t do_swap_page(struct vm_fault *vmf)
pte_unmap_unlock(vmf->pte, vmf->ptl);
out:
/* Clear the swap cache pin for direct swapin after PTL unlock */
- if (need_clear_cache)
+ if (need_clear_cache) {
swapcache_clear(si, entry, nr_pages);
+ if (waitqueue_active(&swapcache_wq))
+ wake_up(&swapcache_wq);
+ }
if (si)
put_swap_device(si);
return ret;
@@ -4620,8 +4628,11 @@ vm_fault_t do_swap_page(struct vm_fault *vmf)
folio_unlock(swapcache);
folio_put(swapcache);
}
- if (need_clear_cache)
+ if (need_clear_cache) {
swapcache_clear(si, entry, nr_pages);
+ if (waitqueue_active(&swapcache_wq))
+ wake_up(&swapcache_wq);
+ }
if (si)
put_swap_device(si);
return ret;
--
2.43.0
The quilt patch titled
Subject: ipc: fix memleak if msg_init_ns failed in create_ipc_ns
has been removed from the -mm tree. Its filename was
ipc-fix-memleak-if-msg_init_ns-failed-in-create_ipc_ns.patch
This patch was dropped because it was merged into the mm-nonmm-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
------------------------------------------------------
From: Wupeng Ma <mawupeng1(a)huawei.com>
Subject: ipc: fix memleak if msg_init_ns failed in create_ipc_ns
Date: Wed, 23 Oct 2024 17:31:29 +0800
From: Ma Wupeng <mawupeng1(a)huawei.com>
Percpu memory allocation may failed during create_ipc_ns however this
fail is not handled properly since ipc sysctls and mq sysctls is not
released properly. Fix this by release these two resource when failure.
Here is the kmemleak stack when percpu failed:
unreferenced object 0xffff88819de2a600 (size 512):
comm "shmem_2nstest", pid 120711, jiffies 4300542254
hex dump (first 32 bytes):
60 aa 9d 84 ff ff ff ff fc 18 48 b2 84 88 ff ff `.........H.....
04 00 00 00 a4 01 00 00 20 e4 56 81 ff ff ff ff ........ .V.....
backtrace (crc be7cba35):
[<ffffffff81b43f83>] __kmalloc_node_track_caller_noprof+0x333/0x420
[<ffffffff81a52e56>] kmemdup_noprof+0x26/0x50
[<ffffffff821b2f37>] setup_mq_sysctls+0x57/0x1d0
[<ffffffff821b29cc>] copy_ipcs+0x29c/0x3b0
[<ffffffff815d6a10>] create_new_namespaces+0x1d0/0x920
[<ffffffff815d7449>] copy_namespaces+0x2e9/0x3e0
[<ffffffff815458f3>] copy_process+0x29f3/0x7ff0
[<ffffffff8154b080>] kernel_clone+0xc0/0x650
[<ffffffff8154b6b1>] __do_sys_clone+0xa1/0xe0
[<ffffffff843df8ff>] do_syscall_64+0xbf/0x1c0
[<ffffffff846000b0>] entry_SYSCALL_64_after_hwframe+0x4b/0x53
Link: https://lkml.kernel.org/r/20241023093129.3074301-1-mawupeng1@huawei.com
Fixes: 72d1e611082e ("ipc/msg: mitigate the lock contention with percpu counter")
Signed-off-by: Ma Wupeng <mawupeng1(a)huawei.com>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
ipc/namespace.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
--- a/ipc/namespace.c~ipc-fix-memleak-if-msg_init_ns-failed-in-create_ipc_ns
+++ a/ipc/namespace.c
@@ -83,13 +83,15 @@ static struct ipc_namespace *create_ipc_
err = msg_init_ns(ns);
if (err)
- goto fail_put;
+ goto fail_ipc;
sem_init_ns(ns);
shm_init_ns(ns);
return ns;
+fail_ipc:
+ retire_ipc_sysctls(ns);
fail_mq:
retire_mq_sysctls(ns);
_
Patches currently in -mm which might be from mawupeng1(a)huawei.com are
The quilt patch titled
Subject: mm/damon/vaddr: fix issue in damon_va_evenly_split_region()
has been removed from the -mm tree. Its filename was
mm-damon-vaddr-fix-issue-in-damon_va_evenly_split_region.patch
This patch was dropped because it was merged into the mm-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
------------------------------------------------------
From: Zheng Yejian <zhengyejian(a)huaweicloud.com>
Subject: mm/damon/vaddr: fix issue in damon_va_evenly_split_region()
Date: Tue, 22 Oct 2024 16:39:26 +0800
Patch series "mm/damon/vaddr: Fix issue in
damon_va_evenly_split_region()". v2.
According to the logic of damon_va_evenly_split_region(), currently
following split case would not meet the expectation:
Suppose DAMON_MIN_REGION=0x1000,
Case: Split [0x0, 0x3000) into 2 pieces, then the result would be
acutually 3 regions:
[0x0, 0x1000), [0x1000, 0x2000), [0x2000, 0x3000)
but NOT the expected 2 regions:
[0x0, 0x1000), [0x1000, 0x3000) !!!
The root cause is that when calculating size of each split piece in
damon_va_evenly_split_region():
`sz_piece = ALIGN_DOWN(sz_orig / nr_pieces, DAMON_MIN_REGION);`
both the dividing and the ALIGN_DOWN may cause loss of precision, then
each time split one piece of size 'sz_piece' from origin 'start' to 'end'
would cause more pieces are split out than expected!!!
To fix it, count for each piece split and make sure no more than
'nr_pieces'. In addition, add above case into damon_test_split_evenly().
And add 'nr_piece == 1' check in damon_va_evenly_split_region() for better
code readability and add a corresponding kunit testcase.
This patch (of 2):
According to the logic of damon_va_evenly_split_region(), currently
following split case would not meet the expectation:
Suppose DAMON_MIN_REGION=0x1000,
Case: Split [0x0, 0x3000) into 2 pieces, then the result would be
acutually 3 regions:
[0x0, 0x1000), [0x1000, 0x2000), [0x2000, 0x3000)
but NOT the expected 2 regions:
[0x0, 0x1000), [0x1000, 0x3000) !!!
The root cause is that when calculating size of each split piece in
damon_va_evenly_split_region():
`sz_piece = ALIGN_DOWN(sz_orig / nr_pieces, DAMON_MIN_REGION);`
both the dividing and the ALIGN_DOWN may cause loss of precision,
then each time split one piece of size 'sz_piece' from origin 'start' to
'end' would cause more pieces are split out than expected!!!
To fix it, count for each piece split and make sure no more than
'nr_pieces'. In addition, add above case into damon_test_split_evenly().
After this patch, damon-operations test passed:
# ./tools/testing/kunit/kunit.py run damon-operations
[...]
============== damon-operations (6 subtests) ===============
[PASSED] damon_test_three_regions_in_vmas
[PASSED] damon_test_apply_three_regions1
[PASSED] damon_test_apply_three_regions2
[PASSED] damon_test_apply_three_regions3
[PASSED] damon_test_apply_three_regions4
[PASSED] damon_test_split_evenly
================ [PASSED] damon-operations =================
Link: https://lkml.kernel.org/r/20241022083927.3592237-1-zhengyejian@huaweicloud.…
Link: https://lkml.kernel.org/r/20241022083927.3592237-2-zhengyejian@huaweicloud.…
Fixes: 3f49584b262c ("mm/damon: implement primitives for the virtual memory address spaces")
Signed-off-by: Zheng Yejian <zhengyejian(a)huaweicloud.com>
Reviewed-by: SeongJae Park <sj(a)kernel.org>
Cc: Fernand Sieber <sieberf(a)amazon.com>
Cc: Leonard Foerster <foersleo(a)amazon.de>
Cc: Shakeel Butt <shakeel.butt(a)linux.dev>
Cc: Ye Weihua <yeweihua4(a)huawei.com>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
mm/damon/tests/vaddr-kunit.h | 1 +
mm/damon/vaddr.c | 4 ++--
2 files changed, 3 insertions(+), 2 deletions(-)
--- a/mm/damon/tests/vaddr-kunit.h~mm-damon-vaddr-fix-issue-in-damon_va_evenly_split_region
+++ a/mm/damon/tests/vaddr-kunit.h
@@ -300,6 +300,7 @@ static void damon_test_split_evenly(stru
damon_test_split_evenly_fail(test, 0, 100, 0);
damon_test_split_evenly_succ(test, 0, 100, 10);
damon_test_split_evenly_succ(test, 5, 59, 5);
+ damon_test_split_evenly_succ(test, 0, 3, 2);
damon_test_split_evenly_fail(test, 5, 6, 2);
}
--- a/mm/damon/vaddr.c~mm-damon-vaddr-fix-issue-in-damon_va_evenly_split_region
+++ a/mm/damon/vaddr.c
@@ -67,6 +67,7 @@ static int damon_va_evenly_split_region(
unsigned long sz_orig, sz_piece, orig_end;
struct damon_region *n = NULL, *next;
unsigned long start;
+ unsigned int i;
if (!r || !nr_pieces)
return -EINVAL;
@@ -80,8 +81,7 @@ static int damon_va_evenly_split_region(
r->ar.end = r->ar.start + sz_piece;
next = damon_next_region(r);
- for (start = r->ar.end; start + sz_piece <= orig_end;
- start += sz_piece) {
+ for (start = r->ar.end, i = 1; i < nr_pieces; start += sz_piece, i++) {
n = damon_new_region(start, start + sz_piece);
if (!n)
return -ENOMEM;
_
Patches currently in -mm which might be from zhengyejian(a)huaweicloud.com are
The quilt patch titled
Subject: mm: resolve faulty mmap_region() error path behaviour
has been removed from the -mm tree. Its filename was
mm-resolve-faulty-mmap_region-error-path-behaviour.patch
This patch was dropped because it was merged into the mm-hotfixes-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
------------------------------------------------------
From: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com>
Subject: mm: resolve faulty mmap_region() error path behaviour
Date: Tue, 29 Oct 2024 18:11:48 +0000
The mmap_region() function is somewhat terrifying, with spaghetti-like
control flow and numerous means by which issues can arise and incomplete
state, memory leaks and other unpleasantness can occur.
A large amount of the complexity arises from trying to handle errors late
in the process of mapping a VMA, which forms the basis of recently
observed issues with resource leaks and observable inconsistent state.
Taking advantage of previous patches in this series we move a number of
checks earlier in the code, simplifying things by moving the core of the
logic into a static internal function __mmap_region().
Doing this allows us to perform a number of checks up front before we do
any real work, and allows us to unwind the writable unmap check
unconditionally as required and to perform a CONFIG_DEBUG_VM_MAPLE_TREE
validation unconditionally also.
We move a number of things here:
1. We preallocate memory for the iterator before we call the file-backed
memory hook, allowing us to exit early and avoid having to perform
complicated and error-prone close/free logic. We carefully free
iterator state on both success and error paths.
2. The enclosing mmap_region() function handles the mapping_map_writable()
logic early. Previously the logic had the mapping_map_writable() at the
point of mapping a newly allocated file-backed VMA, and a matching
mapping_unmap_writable() on success and error paths.
We now do this unconditionally if this is a file-backed, shared writable
mapping. If a driver changes the flags to eliminate VM_MAYWRITE, however
doing so does not invalidate the seal check we just performed, and we in
any case always decrement the counter in the wrapper.
We perform a debug assert to ensure a driver does not attempt to do the
opposite.
3. We also move arch_validate_flags() up into the mmap_region()
function. This is only relevant on arm64 and sparc64, and the check is
only meaningful for SPARC with ADI enabled. We explicitly add a warning
for this arch if a driver invalidates this check, though the code ought
eventually to be fixed to eliminate the need for this.
With all of these measures in place, we no longer need to explicitly close
the VMA on error paths, as we place all checks which might fail prior to a
call to any driver mmap hook.
This eliminates an entire class of errors, makes the code easier to reason
about and more robust.
Link: https://lkml.kernel.org/r/6e0becb36d2f5472053ac5d544c0edfe9b899e25.17302246…
Fixes: deb0f6562884 ("mm/mmap: undo ->mmap() when arch_validate_flags() fails")
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com>
Reported-by: Jann Horn <jannh(a)google.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett(a)oracle.com>
Reviewed-by: Vlastimil Babka <vbabka(a)suse.cz>
Tested-by: Mark Brown <broonie(a)kernel.org>
Cc: Andreas Larsson <andreas(a)gaisler.com>
Cc: Catalin Marinas <catalin.marinas(a)arm.com>
Cc: David S. Miller <davem(a)davemloft.net>
Cc: Helge Deller <deller(a)gmx.de>
Cc: James E.J. Bottomley <James.Bottomley(a)HansenPartnership.com>
Cc: Linus Torvalds <torvalds(a)linux-foundation.org>
Cc: Peter Xu <peterx(a)redhat.com>
Cc: Will Deacon <will(a)kernel.org>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
mm/mmap.c | 121 ++++++++++++++++++++++++++++------------------------
1 file changed, 66 insertions(+), 55 deletions(-)
--- a/mm/mmap.c~mm-resolve-faulty-mmap_region-error-path-behaviour
+++ a/mm/mmap.c
@@ -1358,20 +1358,18 @@ int do_munmap(struct mm_struct *mm, unsi
return do_vmi_munmap(&vmi, mm, start, len, uf, false);
}
-unsigned long mmap_region(struct file *file, unsigned long addr,
+static unsigned long __mmap_region(struct file *file, unsigned long addr,
unsigned long len, vm_flags_t vm_flags, unsigned long pgoff,
struct list_head *uf)
{
struct mm_struct *mm = current->mm;
struct vm_area_struct *vma = NULL;
pgoff_t pglen = PHYS_PFN(len);
- struct vm_area_struct *merge;
unsigned long charged = 0;
struct vma_munmap_struct vms;
struct ma_state mas_detach;
struct maple_tree mt_detach;
unsigned long end = addr + len;
- bool writable_file_mapping = false;
int error;
VMA_ITERATOR(vmi, mm, addr);
VMG_STATE(vmg, mm, &vmi, addr, end, vm_flags, pgoff);
@@ -1445,28 +1443,26 @@ unsigned long mmap_region(struct file *f
vm_flags_init(vma, vm_flags);
vma->vm_page_prot = vm_get_page_prot(vm_flags);
+ if (vma_iter_prealloc(&vmi, vma)) {
+ error = -ENOMEM;
+ goto free_vma;
+ }
+
if (file) {
vma->vm_file = get_file(file);
error = mmap_file(file, vma);
if (error)
- goto unmap_and_free_vma;
-
- if (vma_is_shared_maywrite(vma)) {
- error = mapping_map_writable(file->f_mapping);
- if (error)
- goto close_and_free_vma;
-
- writable_file_mapping = true;
- }
+ goto unmap_and_free_file_vma;
+ /* Drivers cannot alter the address of the VMA. */
+ WARN_ON_ONCE(addr != vma->vm_start);
/*
- * Expansion is handled above, merging is handled below.
- * Drivers should not alter the address of the VMA.
+ * Drivers should not permit writability when previously it was
+ * disallowed.
*/
- if (WARN_ON((addr != vma->vm_start))) {
- error = -EINVAL;
- goto close_and_free_vma;
- }
+ VM_WARN_ON_ONCE(vm_flags != vma->vm_flags &&
+ !(vm_flags & VM_MAYWRITE) &&
+ (vma->vm_flags & VM_MAYWRITE));
vma_iter_config(&vmi, addr, end);
/*
@@ -1474,6 +1470,8 @@ unsigned long mmap_region(struct file *f
* vma again as we may succeed this time.
*/
if (unlikely(vm_flags != vma->vm_flags && vmg.prev)) {
+ struct vm_area_struct *merge;
+
vmg.flags = vma->vm_flags;
/* If this fails, state is reset ready for a reattempt. */
merge = vma_merge_new_range(&vmg);
@@ -1491,7 +1489,7 @@ unsigned long mmap_region(struct file *f
vma = merge;
/* Update vm_flags to pick up the change. */
vm_flags = vma->vm_flags;
- goto unmap_writable;
+ goto file_expanded;
}
vma_iter_config(&vmi, addr, end);
}
@@ -1500,26 +1498,15 @@ unsigned long mmap_region(struct file *f
} else if (vm_flags & VM_SHARED) {
error = shmem_zero_setup(vma);
if (error)
- goto free_vma;
+ goto free_iter_vma;
} else {
vma_set_anonymous(vma);
}
- if (map_deny_write_exec(vma->vm_flags, vma->vm_flags)) {
- error = -EACCES;
- goto close_and_free_vma;
- }
-
- /* Allow architectures to sanity-check the vm_flags */
- if (!arch_validate_flags(vma->vm_flags)) {
- error = -EINVAL;
- goto close_and_free_vma;
- }
-
- if (vma_iter_prealloc(&vmi, vma)) {
- error = -ENOMEM;
- goto close_and_free_vma;
- }
+#ifdef CONFIG_SPARC64
+ /* TODO: Fix SPARC ADI! */
+ WARN_ON_ONCE(!arch_validate_flags(vm_flags));
+#endif
/* Lock the VMA since it is modified after insertion into VMA tree */
vma_start_write(vma);
@@ -1533,10 +1520,7 @@ unsigned long mmap_region(struct file *f
*/
khugepaged_enter_vma(vma, vma->vm_flags);
- /* Once vma denies write, undo our temporary denial count */
-unmap_writable:
- if (writable_file_mapping)
- mapping_unmap_writable(file->f_mapping);
+file_expanded:
file = vma->vm_file;
ksm_add_vma(vma);
expanded:
@@ -1569,23 +1553,17 @@ expanded:
vma_set_page_prot(vma);
- validate_mm(mm);
return addr;
-close_and_free_vma:
- vma_close(vma);
-
- if (file || vma->vm_file) {
-unmap_and_free_vma:
- fput(vma->vm_file);
- vma->vm_file = NULL;
-
- vma_iter_set(&vmi, vma->vm_end);
- /* Undo any partial mapping done by a device driver. */
- unmap_region(&vmi.mas, vma, vmg.prev, vmg.next);
- }
- if (writable_file_mapping)
- mapping_unmap_writable(file->f_mapping);
+unmap_and_free_file_vma:
+ fput(vma->vm_file);
+ vma->vm_file = NULL;
+
+ vma_iter_set(&vmi, vma->vm_end);
+ /* Undo any partial mapping done by a device driver. */
+ unmap_region(&vmi.mas, vma, vmg.prev, vmg.next);
+free_iter_vma:
+ vma_iter_free(&vmi);
free_vma:
vm_area_free(vma);
unacct_error:
@@ -1595,10 +1573,43 @@ unacct_error:
abort_munmap:
vms_abort_munmap_vmas(&vms, &mas_detach);
gather_failed:
- validate_mm(mm);
return error;
}
+unsigned long mmap_region(struct file *file, unsigned long addr,
+ unsigned long len, vm_flags_t vm_flags, unsigned long pgoff,
+ struct list_head *uf)
+{
+ unsigned long ret;
+ bool writable_file_mapping = false;
+
+ /* Check to see if MDWE is applicable. */
+ if (map_deny_write_exec(vm_flags, vm_flags))
+ return -EACCES;
+
+ /* Allow architectures to sanity-check the vm_flags. */
+ if (!arch_validate_flags(vm_flags))
+ return -EINVAL;
+
+ /* Map writable and ensure this isn't a sealed memfd. */
+ if (file && is_shared_maywrite(vm_flags)) {
+ int error = mapping_map_writable(file->f_mapping);
+
+ if (error)
+ return error;
+ writable_file_mapping = true;
+ }
+
+ ret = __mmap_region(file, addr, len, vm_flags, pgoff, uf);
+
+ /* Clear our write mapping regardless of error. */
+ if (writable_file_mapping)
+ mapping_unmap_writable(file->f_mapping);
+
+ validate_mm(current->mm);
+ return ret;
+}
+
static int __vm_munmap(unsigned long start, size_t len, bool unlock)
{
int ret;
_
Patches currently in -mm which might be from lorenzo.stoakes(a)oracle.com are
selftests-mm-add-pkey_sighandler_xx-hugetlb_dio-to-gitignore.patch
mm-refactor-mm_access-to-not-return-null.patch
mm-madvise-unrestrict-process_madvise-for-current-process.patch
maple_tree-do-not-hash-pointers-on-dump-in-debug-mode.patch
tools-testing-fix-phys_addr_t-size-on-64-bit-systems.patch
tools-testing-add-additional-vma_internalh-stubs.patch
mm-isolate-mmap-internal-logic-to-mm-vmac.patch
mm-refactor-__mmap_region.patch
mm-remove-unnecessary-reset-state-logic-on-merge-new-vma.patch
mm-defer-second-attempt-at-merge-on-mmap.patch
mm-pagewalk-add-the-ability-to-install-ptes.patch
mm-add-pte_marker_guard-pte-marker.patch
mm-madvise-implement-lightweight-guard-page-mechanism.patch
tools-testing-update-tools-uapi-header-for-mman-commonh.patch
selftests-mm-add-self-tests-for-guard-page-feature.patch
mm-remove-unnecessary-page_table_lock-on-stack-expansion.patch
The quilt patch titled
Subject: mm: refactor arch_calc_vm_flag_bits() and arm64 MTE handling
has been removed from the -mm tree. Its filename was
mm-refactor-arch_calc_vm_flag_bits-and-arm64-mte-handling.patch
This patch was dropped because it was merged into the mm-hotfixes-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
------------------------------------------------------
From: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com>
Subject: mm: refactor arch_calc_vm_flag_bits() and arm64 MTE handling
Date: Tue, 29 Oct 2024 18:11:47 +0000
Currently MTE is permitted in two circumstances (desiring to use MTE
having been specified by the VM_MTE flag) - where MAP_ANONYMOUS is
specified, as checked by arch_calc_vm_flag_bits() and actualised by
setting the VM_MTE_ALLOWED flag, or if the file backing the mapping is
shmem, in which case we set VM_MTE_ALLOWED in shmem_mmap() when the mmap
hook is activated in mmap_region().
The function that checks that, if VM_MTE is set, VM_MTE_ALLOWED is also
set is the arm64 implementation of arch_validate_flags().
Unfortunately, we intend to refactor mmap_region() to perform this check
earlier, meaning that in the case of a shmem backing we will not have
invoked shmem_mmap() yet, causing the mapping to fail spuriously.
It is inappropriate to set this architecture-specific flag in general mm
code anyway, so a sensible resolution of this issue is to instead move the
check somewhere else.
We resolve this by setting VM_MTE_ALLOWED much earlier in do_mmap(), via
the arch_calc_vm_flag_bits() call.
This is an appropriate place to do this as we already check for the
MAP_ANONYMOUS case here, and the shmem file case is simply a variant of
the same idea - we permit RAM-backed memory.
This requires a modification to the arch_calc_vm_flag_bits() signature to
pass in a pointer to the struct file associated with the mapping, however
this is not too egregious as this is only used by two architectures anyway
- arm64 and parisc.
So this patch performs this adjustment and removes the unnecessary
assignment of VM_MTE_ALLOWED in shmem_mmap().
[akpm(a)linux-foundation.org: fix whitespace, per Catalin]
Link: https://lkml.kernel.org/r/ec251b20ba1964fb64cf1607d2ad80c47f3873df.17302246…
Fixes: deb0f6562884 ("mm/mmap: undo ->mmap() when arch_validate_flags() fails")
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com>
Suggested-by: Catalin Marinas <catalin.marinas(a)arm.com>
Reported-by: Jann Horn <jannh(a)google.com>
Reviewed-by: Catalin Marinas <catalin.marinas(a)arm.com>
Reviewed-by: Vlastimil Babka <vbabka(a)suse.cz>
Cc: Andreas Larsson <andreas(a)gaisler.com>
Cc: David S. Miller <davem(a)davemloft.net>
Cc: Helge Deller <deller(a)gmx.de>
Cc: James E.J. Bottomley <James.Bottomley(a)HansenPartnership.com>
Cc: Liam R. Howlett <Liam.Howlett(a)oracle.com>
Cc: Linus Torvalds <torvalds(a)linux-foundation.org>
Cc: Mark Brown <broonie(a)kernel.org>
Cc: Peter Xu <peterx(a)redhat.com>
Cc: Will Deacon <will(a)kernel.org>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
arch/arm64/include/asm/mman.h | 10 +++++++---
arch/parisc/include/asm/mman.h | 5 +++--
include/linux/mman.h | 7 ++++---
mm/mmap.c | 2 +-
mm/nommu.c | 2 +-
mm/shmem.c | 3 ---
6 files changed, 16 insertions(+), 13 deletions(-)
--- a/arch/arm64/include/asm/mman.h~mm-refactor-arch_calc_vm_flag_bits-and-arm64-mte-handling
+++ a/arch/arm64/include/asm/mman.h
@@ -6,6 +6,8 @@
#ifndef BUILD_VDSO
#include <linux/compiler.h>
+#include <linux/fs.h>
+#include <linux/shmem_fs.h>
#include <linux/types.h>
static inline unsigned long arch_calc_vm_prot_bits(unsigned long prot,
@@ -31,19 +33,21 @@ static inline unsigned long arch_calc_vm
}
#define arch_calc_vm_prot_bits(prot, pkey) arch_calc_vm_prot_bits(prot, pkey)
-static inline unsigned long arch_calc_vm_flag_bits(unsigned long flags)
+static inline unsigned long arch_calc_vm_flag_bits(struct file *file,
+ unsigned long flags)
{
/*
* Only allow MTE on anonymous mappings as these are guaranteed to be
* backed by tags-capable memory. The vm_flags may be overridden by a
* filesystem supporting MTE (RAM-based).
*/
- if (system_supports_mte() && (flags & MAP_ANONYMOUS))
+ if (system_supports_mte() &&
+ ((flags & MAP_ANONYMOUS) || shmem_file(file)))
return VM_MTE_ALLOWED;
return 0;
}
-#define arch_calc_vm_flag_bits(flags) arch_calc_vm_flag_bits(flags)
+#define arch_calc_vm_flag_bits(file, flags) arch_calc_vm_flag_bits(file, flags)
static inline bool arch_validate_prot(unsigned long prot,
unsigned long addr __always_unused)
--- a/arch/parisc/include/asm/mman.h~mm-refactor-arch_calc_vm_flag_bits-and-arm64-mte-handling
+++ a/arch/parisc/include/asm/mman.h
@@ -2,6 +2,7 @@
#ifndef __ASM_MMAN_H__
#define __ASM_MMAN_H__
+#include <linux/fs.h>
#include <uapi/asm/mman.h>
/* PARISC cannot allow mdwe as it needs writable stacks */
@@ -11,7 +12,7 @@ static inline bool arch_memory_deny_writ
}
#define arch_memory_deny_write_exec_supported arch_memory_deny_write_exec_supported
-static inline unsigned long arch_calc_vm_flag_bits(unsigned long flags)
+static inline unsigned long arch_calc_vm_flag_bits(struct file *file, unsigned long flags)
{
/*
* The stack on parisc grows upwards, so if userspace requests memory
@@ -23,6 +24,6 @@ static inline unsigned long arch_calc_vm
return 0;
}
-#define arch_calc_vm_flag_bits(flags) arch_calc_vm_flag_bits(flags)
+#define arch_calc_vm_flag_bits(file, flags) arch_calc_vm_flag_bits(file, flags)
#endif /* __ASM_MMAN_H__ */
--- a/include/linux/mman.h~mm-refactor-arch_calc_vm_flag_bits-and-arm64-mte-handling
+++ a/include/linux/mman.h
@@ -2,6 +2,7 @@
#ifndef _LINUX_MMAN_H
#define _LINUX_MMAN_H
+#include <linux/fs.h>
#include <linux/mm.h>
#include <linux/percpu_counter.h>
@@ -94,7 +95,7 @@ static inline void vm_unacct_memory(long
#endif
#ifndef arch_calc_vm_flag_bits
-#define arch_calc_vm_flag_bits(flags) 0
+#define arch_calc_vm_flag_bits(file, flags) 0
#endif
#ifndef arch_validate_prot
@@ -151,13 +152,13 @@ calc_vm_prot_bits(unsigned long prot, un
* Combine the mmap "flags" argument into "vm_flags" used internally.
*/
static inline unsigned long
-calc_vm_flag_bits(unsigned long flags)
+calc_vm_flag_bits(struct file *file, unsigned long flags)
{
return _calc_vm_trans(flags, MAP_GROWSDOWN, VM_GROWSDOWN ) |
_calc_vm_trans(flags, MAP_LOCKED, VM_LOCKED ) |
_calc_vm_trans(flags, MAP_SYNC, VM_SYNC ) |
_calc_vm_trans(flags, MAP_STACK, VM_NOHUGEPAGE) |
- arch_calc_vm_flag_bits(flags);
+ arch_calc_vm_flag_bits(file, flags);
}
unsigned long vm_commit_limit(void);
--- a/mm/mmap.c~mm-refactor-arch_calc_vm_flag_bits-and-arm64-mte-handling
+++ a/mm/mmap.c
@@ -344,7 +344,7 @@ unsigned long do_mmap(struct file *file,
* to. we assume access permissions have been handled by the open
* of the memory object, so we don't do any here.
*/
- vm_flags |= calc_vm_prot_bits(prot, pkey) | calc_vm_flag_bits(flags) |
+ vm_flags |= calc_vm_prot_bits(prot, pkey) | calc_vm_flag_bits(file, flags) |
mm->def_flags | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC;
/* Obtain the address to map to. we verify (or select) it and ensure
--- a/mm/nommu.c~mm-refactor-arch_calc_vm_flag_bits-and-arm64-mte-handling
+++ a/mm/nommu.c
@@ -842,7 +842,7 @@ static unsigned long determine_vm_flags(
{
unsigned long vm_flags;
- vm_flags = calc_vm_prot_bits(prot, 0) | calc_vm_flag_bits(flags);
+ vm_flags = calc_vm_prot_bits(prot, 0) | calc_vm_flag_bits(file, flags);
if (!file) {
/*
--- a/mm/shmem.c~mm-refactor-arch_calc_vm_flag_bits-and-arm64-mte-handling
+++ a/mm/shmem.c
@@ -2733,9 +2733,6 @@ static int shmem_mmap(struct file *file,
if (ret)
return ret;
- /* arm64 - allow memory tagging on RAM-based files */
- vm_flags_set(vma, VM_MTE_ALLOWED);
-
file_accessed(file);
/* This is anonymous shared memory if it is unlinked at the time of mmap */
if (inode->i_nlink)
_
Patches currently in -mm which might be from lorenzo.stoakes(a)oracle.com are
selftests-mm-add-pkey_sighandler_xx-hugetlb_dio-to-gitignore.patch
mm-refactor-mm_access-to-not-return-null.patch
mm-madvise-unrestrict-process_madvise-for-current-process.patch
maple_tree-do-not-hash-pointers-on-dump-in-debug-mode.patch
tools-testing-fix-phys_addr_t-size-on-64-bit-systems.patch
tools-testing-add-additional-vma_internalh-stubs.patch
mm-isolate-mmap-internal-logic-to-mm-vmac.patch
mm-refactor-__mmap_region.patch
mm-remove-unnecessary-reset-state-logic-on-merge-new-vma.patch
mm-defer-second-attempt-at-merge-on-mmap.patch
mm-pagewalk-add-the-ability-to-install-ptes.patch
mm-add-pte_marker_guard-pte-marker.patch
mm-madvise-implement-lightweight-guard-page-mechanism.patch
tools-testing-update-tools-uapi-header-for-mman-commonh.patch
selftests-mm-add-self-tests-for-guard-page-feature.patch
mm-remove-unnecessary-page_table_lock-on-stack-expansion.patch
The quilt patch titled
Subject: mm: refactor map_deny_write_exec()
has been removed from the -mm tree. Its filename was
mm-refactor-map_deny_write_exec.patch
This patch was dropped because it was merged into the mm-hotfixes-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
------------------------------------------------------
From: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com>
Subject: mm: refactor map_deny_write_exec()
Date: Tue, 29 Oct 2024 18:11:46 +0000
Refactor the map_deny_write_exec() to not unnecessarily require a VMA
parameter but rather to accept VMA flags parameters, which allows us to
use this function early in mmap_region() in a subsequent commit.
While we're here, we refactor the function to be more readable and add
some additional documentation.
Link: https://lkml.kernel.org/r/6be8bb59cd7c68006ebb006eb9d8dc27104b1f70.17302246…
Fixes: deb0f6562884 ("mm/mmap: undo ->mmap() when arch_validate_flags() fails")
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com>
Reported-by: Jann Horn <jannh(a)google.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett(a)oracle.com>
Reviewed-by: Vlastimil Babka <vbabka(a)suse.cz>
Reviewed-by: Jann Horn <jannh(a)google.com>
Cc: Andreas Larsson <andreas(a)gaisler.com>
Cc: Catalin Marinas <catalin.marinas(a)arm.com>
Cc: David S. Miller <davem(a)davemloft.net>
Cc: Helge Deller <deller(a)gmx.de>
Cc: James E.J. Bottomley <James.Bottomley(a)HansenPartnership.com>
Cc: Linus Torvalds <torvalds(a)linux-foundation.org>
Cc: Mark Brown <broonie(a)kernel.org>
Cc: Peter Xu <peterx(a)redhat.com>
Cc: Will Deacon <will(a)kernel.org>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
include/linux/mman.h | 21 ++++++++++++++++++---
mm/mmap.c | 2 +-
mm/mprotect.c | 2 +-
mm/vma.h | 2 +-
4 files changed, 21 insertions(+), 6 deletions(-)
--- a/include/linux/mman.h~mm-refactor-map_deny_write_exec
+++ a/include/linux/mman.h
@@ -188,16 +188,31 @@ static inline bool arch_memory_deny_writ
*
* d) mmap(PROT_READ | PROT_EXEC)
* mmap(PROT_READ | PROT_EXEC | PROT_BTI)
+ *
+ * This is only applicable if the user has set the Memory-Deny-Write-Execute
+ * (MDWE) protection mask for the current process.
+ *
+ * @old specifies the VMA flags the VMA originally possessed, and @new the ones
+ * we propose to set.
+ *
+ * Return: false if proposed change is OK, true if not ok and should be denied.
*/
-static inline bool map_deny_write_exec(struct vm_area_struct *vma, unsigned long vm_flags)
+static inline bool map_deny_write_exec(unsigned long old, unsigned long new)
{
+ /* If MDWE is disabled, we have nothing to deny. */
if (!test_bit(MMF_HAS_MDWE, ¤t->mm->flags))
return false;
- if ((vm_flags & VM_EXEC) && (vm_flags & VM_WRITE))
+ /* If the new VMA is not executable, we have nothing to deny. */
+ if (!(new & VM_EXEC))
+ return false;
+
+ /* Under MDWE we do not accept newly writably executable VMAs... */
+ if (new & VM_WRITE)
return true;
- if (!(vma->vm_flags & VM_EXEC) && (vm_flags & VM_EXEC))
+ /* ...nor previously non-executable VMAs becoming executable. */
+ if (!(old & VM_EXEC))
return true;
return false;
--- a/mm/mmap.c~mm-refactor-map_deny_write_exec
+++ a/mm/mmap.c
@@ -1505,7 +1505,7 @@ unsigned long mmap_region(struct file *f
vma_set_anonymous(vma);
}
- if (map_deny_write_exec(vma, vma->vm_flags)) {
+ if (map_deny_write_exec(vma->vm_flags, vma->vm_flags)) {
error = -EACCES;
goto close_and_free_vma;
}
--- a/mm/mprotect.c~mm-refactor-map_deny_write_exec
+++ a/mm/mprotect.c
@@ -810,7 +810,7 @@ static int do_mprotect_pkey(unsigned lon
break;
}
- if (map_deny_write_exec(vma, newflags)) {
+ if (map_deny_write_exec(vma->vm_flags, newflags)) {
error = -EACCES;
break;
}
--- a/mm/vma.h~mm-refactor-map_deny_write_exec
+++ a/mm/vma.h
@@ -42,7 +42,7 @@ struct vma_munmap_struct {
int vma_count; /* Number of vmas that will be removed */
bool unlock; /* Unlock after the munmap */
bool clear_ptes; /* If there are outstanding PTE to be cleared */
- /* 1 byte hole */
+ /* 2 byte hole */
unsigned long nr_pages; /* Number of pages being removed */
unsigned long locked_vm; /* Number of locked pages */
unsigned long nr_accounted; /* Number of VM_ACCOUNT pages */
_
Patches currently in -mm which might be from lorenzo.stoakes(a)oracle.com are
selftests-mm-add-pkey_sighandler_xx-hugetlb_dio-to-gitignore.patch
mm-refactor-mm_access-to-not-return-null.patch
mm-madvise-unrestrict-process_madvise-for-current-process.patch
maple_tree-do-not-hash-pointers-on-dump-in-debug-mode.patch
tools-testing-fix-phys_addr_t-size-on-64-bit-systems.patch
tools-testing-add-additional-vma_internalh-stubs.patch
mm-isolate-mmap-internal-logic-to-mm-vmac.patch
mm-refactor-__mmap_region.patch
mm-remove-unnecessary-reset-state-logic-on-merge-new-vma.patch
mm-defer-second-attempt-at-merge-on-mmap.patch
mm-pagewalk-add-the-ability-to-install-ptes.patch
mm-add-pte_marker_guard-pte-marker.patch
mm-madvise-implement-lightweight-guard-page-mechanism.patch
tools-testing-update-tools-uapi-header-for-mman-commonh.patch
selftests-mm-add-self-tests-for-guard-page-feature.patch
mm-remove-unnecessary-page_table_lock-on-stack-expansion.patch