The patch titled
Subject: mm/migrate_device.c: add missing flush_cache_page()
has been added to the -mm mm-hotfixes-unstable branch. Its filename is
mm-migrate_devicec-add-missing-flush_cache_page.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patche…
This patch will later appear in the mm-hotfixes-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next via the mm-everything
branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there every 2-3 working days
------------------------------------------------------
From: Alistair Popple <apopple(a)nvidia.com>
Subject: mm/migrate_device.c: add missing flush_cache_page()
Date: Fri, 2 Sep 2022 10:35:52 +1000
Currently we only call flush_cache_page() for the anon_exclusive case,
however in both cases we clear the pte so should flush the cache.
Link: https://lkml.kernel.org/r/5676f30436ab71d1a587ac73f835ed8bd2113ff5.16620785…
Fixes: 8c3328f1f36a ("mm/migrate: migrate_vma() unmap page from vma while collecting pages")
Signed-off-by: Alistair Popple <apopple(a)nvidia.com>
Reviewed-by: David Hildenbrand <david(a)redhat.com>
Cc: Alex Sierra <alex.sierra(a)amd.com>
Cc: Ben Skeggs <bskeggs(a)redhat.com>
Cc: Felix Kuehling <Felix.Kuehling(a)amd.com>
Cc: huang ying <huang.ying.caritas(a)gmail.com>
Cc: "Huang, Ying" <ying.huang(a)intel.com>
Cc: Jason Gunthorpe <jgg(a)nvidia.com>
Cc: John Hubbard <jhubbard(a)nvidia.com>
Cc: Karol Herbst <kherbst(a)redhat.com>
Cc: Logan Gunthorpe <logang(a)deltatee.com>
Cc: Lyude Paul <lyude(a)redhat.com>
Cc: Matthew Wilcox <willy(a)infradead.org>
Cc: Nadav Amit <nadav.amit(a)gmail.com>
Cc: Paul Mackerras <paulus(a)ozlabs.org>
Cc: Peter Xu <peterx(a)redhat.com>
Cc: Ralph Campbell <rcampbell(a)nvidia.com>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
mm/migrate_device.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/mm/migrate_device.c~mm-migrate_devicec-add-missing-flush_cache_page
+++ a/mm/migrate_device.c
@@ -193,9 +193,9 @@ again:
bool anon_exclusive;
pte_t swp_pte;
+ flush_cache_page(vma, addr, pte_pfn(*ptep));
anon_exclusive = PageAnon(page) && PageAnonExclusive(page);
if (anon_exclusive) {
- flush_cache_page(vma, addr, pte_pfn(*ptep));
ptep_clear_flush(vma, addr, ptep);
if (page_try_share_anon_rmap(page)) {
_
Patches currently in -mm which might be from apopple(a)nvidia.com are
mm-migrate_devicec-flush-tlb-while-holding-ptl.patch
mm-migrate_devicec-add-missing-flush_cache_page.patch
mm-migrate_devicec-copy-pte-dirty-bit-to-page.patch
mm-gupc-simplify-and-fix-check_and_migrate_movable_pages-return-codes.patch
selftests-hmm-tests-add-test-for-dirty-bits.patch
mm-gupc-dont-pass-gup_flags-to-check_and_migrate_movable_pages.patch
mm-gupc-refactor-check_and_migrate_movable_pages.patch
mm-migrate_devicec-fix-a-misleading-and-out-dated-comment.patch
The patch titled
Subject: mm/migrate_device.c: flush TLB while holding PTL
has been added to the -mm mm-hotfixes-unstable branch. Its filename is
mm-migrate_devicec-flush-tlb-while-holding-ptl.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patche…
This patch will later appear in the mm-hotfixes-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next via the mm-everything
branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there every 2-3 working days
------------------------------------------------------
From: Alistair Popple <apopple(a)nvidia.com>
Subject: mm/migrate_device.c: flush TLB while holding PTL
Date: Fri, 2 Sep 2022 10:35:51 +1000
When clearing a PTE the TLB should be flushed whilst still holding the PTL
to avoid a potential race with madvise/munmap/etc. For example consider
the following sequence:
CPU0 CPU1
---- ----
migrate_vma_collect_pmd()
pte_unmap_unlock()
madvise(MADV_DONTNEED)
-> zap_pte_range()
pte_offset_map_lock()
[ PTE not present, TLB not flushed ]
pte_unmap_unlock()
[ page is still accessible via stale TLB ]
flush_tlb_range()
In this case the page may still be accessed via the stale TLB entry after
madvise returns. Fix this by flushing the TLB while holding the PTL.
Fixes: 8c3328f1f36a ("mm/migrate: migrate_vma() unmap page from vma while collecting pages")
Link: https://lkml.kernel.org/r/9f801e9d8d830408f2ca27821f606e09aa856899.16620785…
Signed-off-by: Alistair Popple <apopple(a)nvidia.com>
Reported-by: Nadav Amit <nadav.amit(a)gmail.com>
Reviewed-by: "Huang, Ying" <ying.huang(a)intel.com>
Acked-by: David Hildenbrand <david(a)redhat.com>
Cc: Alex Sierra <alex.sierra(a)amd.com>
Cc: Ben Skeggs <bskeggs(a)redhat.com>
Cc: Felix Kuehling <Felix.Kuehling(a)amd.com>
Cc: huang ying <huang.ying.caritas(a)gmail.com>
Cc: Jason Gunthorpe <jgg(a)nvidia.com>
Cc: John Hubbard <jhubbard(a)nvidia.com>
Cc: Karol Herbst <kherbst(a)redhat.com>
Cc: Logan Gunthorpe <logang(a)deltatee.com>
Cc: Lyude Paul <lyude(a)redhat.com>
Cc: Matthew Wilcox <willy(a)infradead.org>
Cc: Paul Mackerras <paulus(a)ozlabs.org>
Cc: Peter Xu <peterx(a)redhat.com>
Cc: Ralph Campbell <rcampbell(a)nvidia.com>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
mm/migrate_device.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
--- a/mm/migrate_device.c~mm-migrate_devicec-flush-tlb-while-holding-ptl
+++ a/mm/migrate_device.c
@@ -254,13 +254,14 @@ next:
migrate->dst[migrate->npages] = 0;
migrate->src[migrate->npages++] = mpfn;
}
- arch_leave_lazy_mmu_mode();
- pte_unmap_unlock(ptep - 1, ptl);
/* Only flush the TLB if we actually modified any entries */
if (unmapped)
flush_tlb_range(walk->vma, start, end);
+ arch_leave_lazy_mmu_mode();
+ pte_unmap_unlock(ptep - 1, ptl);
+
return 0;
}
_
Patches currently in -mm which might be from apopple(a)nvidia.com are
mm-migrate_devicec-flush-tlb-while-holding-ptl.patch
mm-migrate_devicec-add-missing-flush_cache_page.patch
mm-migrate_devicec-copy-pte-dirty-bit-to-page.patch
mm-gupc-simplify-and-fix-check_and_migrate_movable_pages-return-codes.patch
selftests-hmm-tests-add-test-for-dirty-bits.patch
mm-gupc-dont-pass-gup_flags-to-check_and_migrate_movable_pages.patch
mm-gupc-refactor-check_and_migrate_movable_pages.patch
mm-migrate_devicec-fix-a-misleading-and-out-dated-comment.patch