This is a note to let you know that I've just added the patch titled
mm/madvise.c: fix madvise() infinite loop under special circumstances
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
mm-madvise.c-fix-madvise-infinite-loop-under-special-circumstances.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From 6ea8d958a2c95a1d514015d4e29ba21a8c0a1a91 Mon Sep 17 00:00:00 2001
From: chenjie <chenjie6(a)huawei.com>
Date: Wed, 29 Nov 2017 16:10:54 -0800
Subject: mm/madvise.c: fix madvise() infinite loop under special circumstances
From: chenjie <chenjie6(a)huawei.com>
commit 6ea8d958a2c95a1d514015d4e29ba21a8c0a1a91 upstream.
MADVISE_WILLNEED has always been a noop for DAX (formerly XIP) mappings.
Unfortunately madvise_willneed() doesn't communicate this information
properly to the generic madvise syscall implementation. The calling
convention is quite subtle there. madvise_vma() is supposed to either
return an error or update &prev otherwise the main loop will never
advance to the next vma and it will keep looping for ever without a way
to get out of the kernel.
It seems this has been broken since introduction. Nobody has noticed
because nobody seems to be using MADVISE_WILLNEED on these DAX mappings.
[mhocko(a)suse.com: rewrite changelog]
Link: http://lkml.kernel.org/r/20171127115318.911-1-guoxuenan@huawei.com
Fixes: fe77ba6f4f97 ("[PATCH] xip: madvice/fadvice: execute in place")
Signed-off-by: chenjie <chenjie6(a)huawei.com>
Signed-off-by: guoxuenan <guoxuenan(a)huawei.com>
Acked-by: Michal Hocko <mhocko(a)suse.com>
Cc: Minchan Kim <minchan(a)kernel.org>
Cc: zhangyi (F) <yi.zhang(a)huawei.com>
Cc: Miao Xie <miaoxie(a)huawei.com>
Cc: Mike Rapoport <rppt(a)linux.vnet.ibm.com>
Cc: Shaohua Li <shli(a)fb.com>
Cc: Andrea Arcangeli <aarcange(a)redhat.com>
Cc: Mel Gorman <mgorman(a)techsingularity.net>
Cc: Kirill A. Shutemov <kirill.shutemov(a)linux.intel.com>
Cc: David Rientjes <rientjes(a)google.com>
Cc: Anshuman Khandual <khandual(a)linux.vnet.ibm.com>
Cc: Rik van Riel <riel(a)redhat.com>
Cc: Carsten Otte <cotte(a)de.ibm.com>
Cc: Dan Williams <dan.j.williams(a)intel.com>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
mm/madvise.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)
--- a/mm/madvise.c
+++ b/mm/madvise.c
@@ -223,15 +223,14 @@ static long madvise_willneed(struct vm_a
{
struct file *file = vma->vm_file;
+ *prev = vma;
#ifdef CONFIG_SWAP
if (!file) {
- *prev = vma;
force_swapin_readahead(vma, start, end);
return 0;
}
if (shmem_mapping(file->f_mapping)) {
- *prev = vma;
force_shm_swapin_readahead(vma, start, end,
file->f_mapping);
return 0;
@@ -246,7 +245,6 @@ static long madvise_willneed(struct vm_a
return 0;
}
- *prev = vma;
start = ((start - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
if (end > vma->vm_end)
end = vma->vm_end;
Patches currently in stable-queue which might be from chenjie6(a)huawei.com are
queue-4.4/mm-madvise.c-fix-madvise-infinite-loop-under-special-circumstances.patch
This is a note to let you know that I've just added the patch titled
v4l2: disable filesystem-dax mapping support
to the 4.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
v4l2-disable-filesystem-dax-mapping-support.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From b70131de648c2b997d22f4653934438013f407a1 Mon Sep 17 00:00:00 2001
From: Dan Williams <dan.j.williams(a)intel.com>
Date: Wed, 29 Nov 2017 16:10:43 -0800
Subject: v4l2: disable filesystem-dax mapping support
From: Dan Williams <dan.j.williams(a)intel.com>
commit b70131de648c2b997d22f4653934438013f407a1 upstream.
V4L2 memory registrations are incompatible with filesystem-dax that
needs the ability to revoke dma access to a mapping at will, or
otherwise allow the kernel to wait for completion of DMA. The
filesystem-dax implementation breaks the traditional solution of
truncate of active file backed mappings since there is no page-cache
page we can orphan to sustain ongoing DMA.
If v4l2 wants to support long lived DMA mappings it needs to arrange to
hold a file lease or use some other mechanism so that the kernel can
coordinate revoking DMA access when the filesystem needs to truncate
mappings.
Link: http://lkml.kernel.org/r/151068940499.7446.12846708245365671207.stgit@dwill…
Fixes: 3565fce3a659 ("mm, x86: get_user_pages() for dax mappings")
Signed-off-by: Dan Williams <dan.j.williams(a)intel.com>
Reported-by: Jan Kara <jack(a)suse.cz>
Reviewed-by: Jan Kara <jack(a)suse.cz>
Cc: Mauro Carvalho Chehab <mchehab(a)kernel.org>
Cc: Christoph Hellwig <hch(a)lst.de>
Cc: Doug Ledford <dledford(a)redhat.com>
Cc: Hal Rosenstock <hal.rosenstock(a)gmail.com>
Cc: Inki Dae <inki.dae(a)samsung.com>
Cc: Jason Gunthorpe <jgg(a)mellanox.com>
Cc: Jeff Moyer <jmoyer(a)redhat.com>
Cc: Joonyoung Shim <jy0922.shim(a)samsung.com>
Cc: Kyungmin Park <kyungmin.park(a)samsung.com>
Cc: Mel Gorman <mgorman(a)suse.de>
Cc: Ross Zwisler <ross.zwisler(a)linux.intel.com>
Cc: Sean Hefty <sean.hefty(a)intel.com>
Cc: Seung-Woo Kim <sw0312.kim(a)samsung.com>
Cc: Vlastimil Babka <vbabka(a)suse.cz>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
drivers/media/v4l2-core/videobuf-dma-sg.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
--- a/drivers/media/v4l2-core/videobuf-dma-sg.c
+++ b/drivers/media/v4l2-core/videobuf-dma-sg.c
@@ -185,12 +185,13 @@ static int videobuf_dma_init_user_locked
dprintk(1, "init user [0x%lx+0x%lx => %d pages]\n",
data, size, dma->nr_pages);
- err = get_user_pages(data & PAGE_MASK, dma->nr_pages,
+ err = get_user_pages_longterm(data & PAGE_MASK, dma->nr_pages,
flags, dma->pages, NULL);
if (err != dma->nr_pages) {
dma->nr_pages = (err >= 0) ? err : 0;
- dprintk(1, "get_user_pages: err=%d [%d]\n", err, dma->nr_pages);
+ dprintk(1, "get_user_pages_longterm: err=%d [%d]\n", err,
+ dma->nr_pages);
return err < 0 ? err : -EINVAL;
}
return 0;
Patches currently in stable-queue which might be from dan.j.williams(a)intel.com are
queue-4.14/mm-hugetlbfs-introduce-split-to-vm_operations_struct.patch
queue-4.14/ib-core-disable-memory-registration-of-filesystem-dax-vmas.patch
queue-4.14/mm-introduce-get_user_pages_longterm.patch
queue-4.14/mm-fail-get_vaddr_frames-for-filesystem-dax-mappings.patch
queue-4.14/device-dax-implement-split-to-catch-invalid-munmap-attempts.patch
queue-4.14/v4l2-disable-filesystem-dax-mapping-support.patch
queue-4.14/mm-fix-device-dax-pud-write-faults-triggered-by-get_user_pages.patch
queue-4.14/mm-madvise.c-fix-madvise-infinite-loop-under-special-circumstances.patch
This is a note to let you know that I've just added the patch titled
mm, thp: Do not make page table dirty unconditionally in touch_p[mu]d()
to the 4.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
mm-thp-do-not-make-page-table-dirty-unconditionally-in-touch_pd.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From a8f97366452ed491d13cf1e44241bc0b5740b1f0 Mon Sep 17 00:00:00 2001
From: "Kirill A. Shutemov" <kirill.shutemov(a)linux.intel.com>
Date: Mon, 27 Nov 2017 06:21:25 +0300
Subject: mm, thp: Do not make page table dirty unconditionally in touch_p[mu]d()
From: Kirill A. Shutemov <kirill.shutemov(a)linux.intel.com>
commit a8f97366452ed491d13cf1e44241bc0b5740b1f0 upstream.
Currently, we unconditionally make page table dirty in touch_pmd().
It may result in false-positive can_follow_write_pmd().
We may avoid the situation, if we would only make the page table entry
dirty if caller asks for write access -- FOLL_WRITE.
The patch also changes touch_pud() in the same way.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov(a)linux.intel.com>
Cc: Michal Hocko <mhocko(a)suse.com>
Cc: Hugh Dickins <hughd(a)google.com>
Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
mm/huge_memory.c | 36 +++++++++++++-----------------------
1 file changed, 13 insertions(+), 23 deletions(-)
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -842,20 +842,15 @@ EXPORT_SYMBOL_GPL(vmf_insert_pfn_pud);
#endif /* CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD */
static void touch_pmd(struct vm_area_struct *vma, unsigned long addr,
- pmd_t *pmd)
+ pmd_t *pmd, int flags)
{
pmd_t _pmd;
- /*
- * We should set the dirty bit only for FOLL_WRITE but for now
- * the dirty bit in the pmd is meaningless. And if the dirty
- * bit will become meaningful and we'll only set it with
- * FOLL_WRITE, an atomic set_bit will be required on the pmd to
- * set the young bit, instead of the current set_pmd_at.
- */
- _pmd = pmd_mkyoung(pmd_mkdirty(*pmd));
+ _pmd = pmd_mkyoung(*pmd);
+ if (flags & FOLL_WRITE)
+ _pmd = pmd_mkdirty(_pmd);
if (pmdp_set_access_flags(vma, addr & HPAGE_PMD_MASK,
- pmd, _pmd, 1))
+ pmd, _pmd, flags & FOLL_WRITE))
update_mmu_cache_pmd(vma, addr, pmd);
}
@@ -884,7 +879,7 @@ struct page *follow_devmap_pmd(struct vm
return NULL;
if (flags & FOLL_TOUCH)
- touch_pmd(vma, addr, pmd);
+ touch_pmd(vma, addr, pmd, flags);
/*
* device mapped pages can only be returned if the
@@ -995,20 +990,15 @@ out:
#ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
static void touch_pud(struct vm_area_struct *vma, unsigned long addr,
- pud_t *pud)
+ pud_t *pud, int flags)
{
pud_t _pud;
- /*
- * We should set the dirty bit only for FOLL_WRITE but for now
- * the dirty bit in the pud is meaningless. And if the dirty
- * bit will become meaningful and we'll only set it with
- * FOLL_WRITE, an atomic set_bit will be required on the pud to
- * set the young bit, instead of the current set_pud_at.
- */
- _pud = pud_mkyoung(pud_mkdirty(*pud));
+ _pud = pud_mkyoung(*pud);
+ if (flags & FOLL_WRITE)
+ _pud = pud_mkdirty(_pud);
if (pudp_set_access_flags(vma, addr & HPAGE_PUD_MASK,
- pud, _pud, 1))
+ pud, _pud, flags & FOLL_WRITE))
update_mmu_cache_pud(vma, addr, pud);
}
@@ -1031,7 +1021,7 @@ struct page *follow_devmap_pud(struct vm
return NULL;
if (flags & FOLL_TOUCH)
- touch_pud(vma, addr, pud);
+ touch_pud(vma, addr, pud, flags);
/*
* device mapped pages can only be returned if the
@@ -1407,7 +1397,7 @@ struct page *follow_trans_huge_pmd(struc
page = pmd_page(*pmd);
VM_BUG_ON_PAGE(!PageHead(page) && !is_zone_device_page(page), page);
if (flags & FOLL_TOUCH)
- touch_pmd(vma, addr, pmd);
+ touch_pmd(vma, addr, pmd, flags);
if ((flags & FOLL_MLOCK) && (vma->vm_flags & VM_LOCKED)) {
/*
* We don't mlock() pte-mapped THPs. This way we can avoid
Patches currently in stable-queue which might be from kirill.shutemov(a)linux.intel.com are
queue-4.14/mm-fix-device-dax-pud-write-faults-triggered-by-get_user_pages.patch
queue-4.14/mm-hugetlb-fix-null-pointer-dereference-on-5-level-paging-machine.patch
queue-4.14/mm-thp-do-not-make-page-table-dirty-unconditionally-in-touch_pd.patch
queue-4.14/mm-madvise.c-fix-madvise-infinite-loop-under-special-circumstances.patch
This is a note to let you know that I've just added the patch titled
mm: migrate: fix an incorrect call of prep_transhuge_page()
to the 4.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
mm-migrate-fix-an-incorrect-call-of-prep_transhuge_page.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From 40a899ed16486455f964e46d1af31fd4fded21c1 Mon Sep 17 00:00:00 2001
From: Zi Yan <zi.yan(a)cs.rutgers.edu>
Date: Wed, 29 Nov 2017 16:11:12 -0800
Subject: mm: migrate: fix an incorrect call of prep_transhuge_page()
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
From: Zi Yan <zi.yan(a)cs.rutgers.edu>
commit 40a899ed16486455f964e46d1af31fd4fded21c1 upstream.
In https://lkml.org/lkml/2017/11/20/411, Andrea reported that during
memory hotplug/hot remove prep_transhuge_page() is called incorrectly on
non-THP pages for migration, when THP is on but THP migration is not
enabled. This leads to a bad state of target pages for migration.
By inspecting the code, if called on a non-THP, prep_transhuge_page()
will
1) change the value of the mapping of (page + 2), since it is used for
THP deferred list;
2) change the lru value of (page + 1), since it is used for THP's dtor.
Both can lead to data corruption of these two pages.
Andrea said:
"Pragmatically and from the point of view of the memory_hotplug subsys,
the effect is a kernel crash when pages are being migrated during a
memory hot remove offline and migration target pages are found in a
bad state"
This patch fixes it by only calling prep_transhuge_page() when we are
certain that the target page is THP.
Link: http://lkml.kernel.org/r/20171121021855.50525-1-zi.yan@sent.com
Fixes: 8135d8926c08 ("mm: memory_hotplug: memory hotremove supports thp migration")
Signed-off-by: Zi Yan <zi.yan(a)cs.rutgers.edu>
Reported-by: Andrea Reale <ar(a)linux.vnet.ibm.com>
Cc: Naoya Horiguchi <n-horiguchi(a)ah.jp.nec.com>
Cc: Michal Hocko <mhocko(a)kernel.org>
Cc: "Jérôme Glisse" <jglisse(a)redhat.com>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
diff --git a/include/linux/migrate.h b/include/linux/migrate.h
index 895ec0c4942e..a2246cf670ba 100644
--- a/include/linux/migrate.h
+++ b/include/linux/migrate.h
@@ -54,7 +54,7 @@ static inline struct page *new_page_nodemask(struct page *page,
new_page = __alloc_pages_nodemask(gfp_mask, order,
preferred_nid, nodemask);
- if (new_page && PageTransHuge(page))
+ if (new_page && PageTransHuge(new_page))
prep_transhuge_page(new_page);
return new_page;
Patches currently in stable-queue which might be from zi.yan(a)cs.rutgers.edu are
queue-4.14/mm-migrate-fix-an-incorrect-call-of-prep_transhuge_page.patch
This is a note to let you know that I've just added the patch titled
mm, memcg: fix mem_cgroup_swapout() for THPs
to the 4.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
mm-memcg-fix-mem_cgroup_swapout-for-thps.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From d08afa149acfd00871484ada6dabc3880524cd1c Mon Sep 17 00:00:00 2001
From: Shakeel Butt <shakeelb(a)google.com>
Date: Wed, 29 Nov 2017 16:11:15 -0800
Subject: mm, memcg: fix mem_cgroup_swapout() for THPs
From: Shakeel Butt <shakeelb(a)google.com>
commit d08afa149acfd00871484ada6dabc3880524cd1c upstream.
Commit d6810d730022 ("memcg, THP, swap: make mem_cgroup_swapout()
support THP") changed mem_cgroup_swapout() to support transparent huge
page (THP).
However the patch missed one location which should be changed for
correctly handling THPs. The resulting bug will cause the memory
cgroups whose THPs were swapped out to become zombies on deletion.
Link: http://lkml.kernel.org/r/20171128161941.20931-1-shakeelb@google.com
Fixes: d6810d730022 ("memcg, THP, swap: make mem_cgroup_swapout() support THP")
Signed-off-by: Shakeel Butt <shakeelb(a)google.com>
Acked-by: Johannes Weiner <hannes(a)cmpxchg.org>
Acked-by: Michal Hocko <mhocko(a)suse.com>
Cc: Huang Ying <ying.huang(a)intel.com>
Cc: Vladimir Davydov <vdavydov.dev(a)gmail.com>
Cc: Greg Thelen <gthelen(a)google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org>
---
mm/memcontrol.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -6044,7 +6044,7 @@ void mem_cgroup_swapout(struct page *pag
memcg_check_events(memcg, page);
if (!mem_cgroup_is_root(memcg))
- css_put(&memcg->css);
+ css_put_many(&memcg->css, nr_entries);
}
/**
Patches currently in stable-queue which might be from shakeelb(a)google.com are
queue-4.14/mm-memcg-fix-mem_cgroup_swapout-for-thps.patch
This is a note to let you know that I've just added the patch titled
mm/madvise.c: fix madvise() infinite loop under special circumstances
to the 4.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
mm-madvise.c-fix-madvise-infinite-loop-under-special-circumstances.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From 6ea8d958a2c95a1d514015d4e29ba21a8c0a1a91 Mon Sep 17 00:00:00 2001
From: chenjie <chenjie6(a)huawei.com>
Date: Wed, 29 Nov 2017 16:10:54 -0800
Subject: mm/madvise.c: fix madvise() infinite loop under special circumstances
From: chenjie <chenjie6(a)huawei.com>
commit 6ea8d958a2c95a1d514015d4e29ba21a8c0a1a91 upstream.
MADVISE_WILLNEED has always been a noop for DAX (formerly XIP) mappings.
Unfortunately madvise_willneed() doesn't communicate this information
properly to the generic madvise syscall implementation. The calling
convention is quite subtle there. madvise_vma() is supposed to either
return an error or update &prev otherwise the main loop will never
advance to the next vma and it will keep looping for ever without a way
to get out of the kernel.
It seems this has been broken since introduction. Nobody has noticed
because nobody seems to be using MADVISE_WILLNEED on these DAX mappings.
[mhocko(a)suse.com: rewrite changelog]
Link: http://lkml.kernel.org/r/20171127115318.911-1-guoxuenan@huawei.com
Fixes: fe77ba6f4f97 ("[PATCH] xip: madvice/fadvice: execute in place")
Signed-off-by: chenjie <chenjie6(a)huawei.com>
Signed-off-by: guoxuenan <guoxuenan(a)huawei.com>
Acked-by: Michal Hocko <mhocko(a)suse.com>
Cc: Minchan Kim <minchan(a)kernel.org>
Cc: zhangyi (F) <yi.zhang(a)huawei.com>
Cc: Miao Xie <miaoxie(a)huawei.com>
Cc: Mike Rapoport <rppt(a)linux.vnet.ibm.com>
Cc: Shaohua Li <shli(a)fb.com>
Cc: Andrea Arcangeli <aarcange(a)redhat.com>
Cc: Mel Gorman <mgorman(a)techsingularity.net>
Cc: Kirill A. Shutemov <kirill.shutemov(a)linux.intel.com>
Cc: David Rientjes <rientjes(a)google.com>
Cc: Anshuman Khandual <khandual(a)linux.vnet.ibm.com>
Cc: Rik van Riel <riel(a)redhat.com>
Cc: Carsten Otte <cotte(a)de.ibm.com>
Cc: Dan Williams <dan.j.williams(a)intel.com>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
mm/madvise.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)
--- a/mm/madvise.c
+++ b/mm/madvise.c
@@ -276,15 +276,14 @@ static long madvise_willneed(struct vm_a
{
struct file *file = vma->vm_file;
+ *prev = vma;
#ifdef CONFIG_SWAP
if (!file) {
- *prev = vma;
force_swapin_readahead(vma, start, end);
return 0;
}
if (shmem_mapping(file->f_mapping)) {
- *prev = vma;
force_shm_swapin_readahead(vma, start, end,
file->f_mapping);
return 0;
@@ -299,7 +298,6 @@ static long madvise_willneed(struct vm_a
return 0;
}
- *prev = vma;
start = ((start - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
if (end > vma->vm_end)
end = vma->vm_end;
Patches currently in stable-queue which might be from chenjie6(a)huawei.com are
queue-4.14/mm-madvise.c-fix-madvise-infinite-loop-under-special-circumstances.patch
This is a note to let you know that I've just added the patch titled
mm: introduce get_user_pages_longterm
to the 4.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
mm-introduce-get_user_pages_longterm.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From 2bb6d2837083de722bfdc369cb0d76ce188dd9b4 Mon Sep 17 00:00:00 2001
From: Dan Williams <dan.j.williams(a)intel.com>
Date: Wed, 29 Nov 2017 16:10:35 -0800
Subject: mm: introduce get_user_pages_longterm
From: Dan Williams <dan.j.williams(a)intel.com>
commit 2bb6d2837083de722bfdc369cb0d76ce188dd9b4 upstream.
Patch series "introduce get_user_pages_longterm()", v2.
Here is a new get_user_pages api for cases where a driver intends to
keep an elevated page count indefinitely. This is distinct from usages
like iov_iter_get_pages where the elevated page counts are transient.
The iov_iter_get_pages cases immediately turn around and submit the
pages to a device driver which will put_page when the i/o operation
completes (under kernel control).
In the longterm case userspace is responsible for dropping the page
reference at some undefined point in the future. This is untenable for
filesystem-dax case where the filesystem is in control of the lifetime
of the block / page and needs reasonable limits on how long it can wait
for pages in a mapping to become idle.
Fixing filesystems to actually wait for dax pages to be idle before
blocks from a truncate/hole-punch operation are repurposed is saved for
a later patch series.
Also, allowing longterm registration of dax mappings is a future patch
series that introduces a "map with lease" semantic where the kernel can
revoke a lease and force userspace to drop its page references.
I have also tagged these for -stable to purposely break cases that might
assume that longterm memory registrations for filesystem-dax mappings
were supported by the kernel. The behavior regression this policy
change implies is one of the reasons we maintain the "dax enabled.
Warning: EXPERIMENTAL, use at your own risk" notification when mounting
a filesystem in dax mode.
It is worth noting the device-dax interface does not suffer the same
constraints since it does not support file space management operations
like hole-punch.
This patch (of 4):
Until there is a solution to the dma-to-dax vs truncate problem it is
not safe to allow long standing memory registrations against
filesytem-dax vmas. Device-dax vmas do not have this problem and are
explicitly allowed.
This is temporary until a "memory registration with layout-lease"
mechanism can be implemented for the affected sub-systems (RDMA and
V4L2).
[akpm(a)linux-foundation.org: use kcalloc()]
Link: http://lkml.kernel.org/r/151068939435.7446.13560129395419350737.stgit@dwill…
Fixes: 3565fce3a659 ("mm, x86: get_user_pages() for dax mappings")
Signed-off-by: Dan Williams <dan.j.williams(a)intel.com>
Suggested-by: Christoph Hellwig <hch(a)lst.de>
Cc: Doug Ledford <dledford(a)redhat.com>
Cc: Hal Rosenstock <hal.rosenstock(a)gmail.com>
Cc: Inki Dae <inki.dae(a)samsung.com>
Cc: Jan Kara <jack(a)suse.cz>
Cc: Jason Gunthorpe <jgg(a)mellanox.com>
Cc: Jeff Moyer <jmoyer(a)redhat.com>
Cc: Joonyoung Shim <jy0922.shim(a)samsung.com>
Cc: Kyungmin Park <kyungmin.park(a)samsung.com>
Cc: Mauro Carvalho Chehab <mchehab(a)kernel.org>
Cc: Mel Gorman <mgorman(a)suse.de>
Cc: Ross Zwisler <ross.zwisler(a)linux.intel.com>
Cc: Sean Hefty <sean.hefty(a)intel.com>
Cc: Seung-Woo Kim <sw0312.kim(a)samsung.com>
Cc: Vlastimil Babka <vbabka(a)suse.cz>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
include/linux/fs.h | 14 +++++++++++
include/linux/mm.h | 13 ++++++++++
mm/gup.c | 64 +++++++++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 91 insertions(+)
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -3175,6 +3175,20 @@ static inline bool vma_is_dax(struct vm_
return vma->vm_file && IS_DAX(vma->vm_file->f_mapping->host);
}
+static inline bool vma_is_fsdax(struct vm_area_struct *vma)
+{
+ struct inode *inode;
+
+ if (!vma->vm_file)
+ return false;
+ if (!vma_is_dax(vma))
+ return false;
+ inode = file_inode(vma->vm_file);
+ if (inode->i_mode == S_IFCHR)
+ return false; /* device-dax */
+ return true;
+}
+
static inline int iocb_flags(struct file *file)
{
int res = 0;
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1368,6 +1368,19 @@ long get_user_pages_locked(unsigned long
unsigned int gup_flags, struct page **pages, int *locked);
long get_user_pages_unlocked(unsigned long start, unsigned long nr_pages,
struct page **pages, unsigned int gup_flags);
+#ifdef CONFIG_FS_DAX
+long get_user_pages_longterm(unsigned long start, unsigned long nr_pages,
+ unsigned int gup_flags, struct page **pages,
+ struct vm_area_struct **vmas);
+#else
+static inline long get_user_pages_longterm(unsigned long start,
+ unsigned long nr_pages, unsigned int gup_flags,
+ struct page **pages, struct vm_area_struct **vmas)
+{
+ return get_user_pages(start, nr_pages, gup_flags, pages, vmas);
+}
+#endif /* CONFIG_FS_DAX */
+
int get_user_pages_fast(unsigned long start, int nr_pages, int write,
struct page **pages);
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -1095,6 +1095,70 @@ long get_user_pages(unsigned long start,
}
EXPORT_SYMBOL(get_user_pages);
+#ifdef CONFIG_FS_DAX
+/*
+ * This is the same as get_user_pages() in that it assumes we are
+ * operating on the current task's mm, but it goes further to validate
+ * that the vmas associated with the address range are suitable for
+ * longterm elevated page reference counts. For example, filesystem-dax
+ * mappings are subject to the lifetime enforced by the filesystem and
+ * we need guarantees that longterm users like RDMA and V4L2 only
+ * establish mappings that have a kernel enforced revocation mechanism.
+ *
+ * "longterm" == userspace controlled elevated page count lifetime.
+ * Contrast this to iov_iter_get_pages() usages which are transient.
+ */
+long get_user_pages_longterm(unsigned long start, unsigned long nr_pages,
+ unsigned int gup_flags, struct page **pages,
+ struct vm_area_struct **vmas_arg)
+{
+ struct vm_area_struct **vmas = vmas_arg;
+ struct vm_area_struct *vma_prev = NULL;
+ long rc, i;
+
+ if (!pages)
+ return -EINVAL;
+
+ if (!vmas) {
+ vmas = kcalloc(nr_pages, sizeof(struct vm_area_struct *),
+ GFP_KERNEL);
+ if (!vmas)
+ return -ENOMEM;
+ }
+
+ rc = get_user_pages(start, nr_pages, gup_flags, pages, vmas);
+
+ for (i = 0; i < rc; i++) {
+ struct vm_area_struct *vma = vmas[i];
+
+ if (vma == vma_prev)
+ continue;
+
+ vma_prev = vma;
+
+ if (vma_is_fsdax(vma))
+ break;
+ }
+
+ /*
+ * Either get_user_pages() failed, or the vma validation
+ * succeeded, in either case we don't need to put_page() before
+ * returning.
+ */
+ if (i >= rc)
+ goto out;
+
+ for (i = 0; i < rc; i++)
+ put_page(pages[i]);
+ rc = -EOPNOTSUPP;
+out:
+ if (vmas != vmas_arg)
+ kfree(vmas);
+ return rc;
+}
+EXPORT_SYMBOL(get_user_pages_longterm);
+#endif /* CONFIG_FS_DAX */
+
/**
* populate_vma_page_range() - populate a range of pages in the vma.
* @vma: target vma
Patches currently in stable-queue which might be from dan.j.williams(a)intel.com are
queue-4.14/mm-hugetlbfs-introduce-split-to-vm_operations_struct.patch
queue-4.14/ib-core-disable-memory-registration-of-filesystem-dax-vmas.patch
queue-4.14/mm-introduce-get_user_pages_longterm.patch
queue-4.14/mm-fail-get_vaddr_frames-for-filesystem-dax-mappings.patch
queue-4.14/device-dax-implement-split-to-catch-invalid-munmap-attempts.patch
queue-4.14/v4l2-disable-filesystem-dax-mapping-support.patch
queue-4.14/mm-fix-device-dax-pud-write-faults-triggered-by-get_user_pages.patch
queue-4.14/mm-madvise.c-fix-madvise-infinite-loop-under-special-circumstances.patch
This is a note to let you know that I've just added the patch titled
mm, hugetlbfs: introduce ->split() to vm_operations_struct
to the 4.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
mm-hugetlbfs-introduce-split-to-vm_operations_struct.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From 31383c6865a578834dd953d9dbc88e6b19fe3997 Mon Sep 17 00:00:00 2001
From: Dan Williams <dan.j.williams(a)intel.com>
Date: Wed, 29 Nov 2017 16:10:28 -0800
Subject: mm, hugetlbfs: introduce ->split() to vm_operations_struct
From: Dan Williams <dan.j.williams(a)intel.com>
commit 31383c6865a578834dd953d9dbc88e6b19fe3997 upstream.
Patch series "device-dax: fix unaligned munmap handling"
When device-dax is operating in huge-page mode we want it to behave like
hugetlbfs and fail attempts to split vmas into unaligned ranges. It
would be messy to teach the munmap path about device-dax alignment
constraints in the same (hstate) way that hugetlbfs communicates this
constraint. Instead, these patches introduce a new ->split() vm
operation.
This patch (of 2):
The device-dax interface has similar constraints as hugetlbfs in that it
requires the munmap path to unmap in huge page aligned units. Rather
than add more custom vma handling code in __split_vma() introduce a new
vm operation to perform this vma specific check.
Link: http://lkml.kernel.org/r/151130418135.4029.6783191281930729710.stgit@dwilli…
Fixes: dee410792419 ("/dev/dax, core: file operations and dax-mmap")
Signed-off-by: Dan Williams <dan.j.williams(a)intel.com>
Cc: Jeff Moyer <jmoyer(a)redhat.com>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
include/linux/mm.h | 1 +
mm/hugetlb.c | 8 ++++++++
mm/mmap.c | 8 +++++---
3 files changed, 14 insertions(+), 3 deletions(-)
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -367,6 +367,7 @@ enum page_entry_size {
struct vm_operations_struct {
void (*open)(struct vm_area_struct * area);
void (*close)(struct vm_area_struct * area);
+ int (*split)(struct vm_area_struct * area, unsigned long addr);
int (*mremap)(struct vm_area_struct * area);
int (*fault)(struct vm_fault *vmf);
int (*huge_fault)(struct vm_fault *vmf, enum page_entry_size pe_size);
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -3125,6 +3125,13 @@ static void hugetlb_vm_op_close(struct v
}
}
+static int hugetlb_vm_op_split(struct vm_area_struct *vma, unsigned long addr)
+{
+ if (addr & ~(huge_page_mask(hstate_vma(vma))))
+ return -EINVAL;
+ return 0;
+}
+
/*
* We cannot handle pagefaults against hugetlb pages at all. They cause
* handle_mm_fault() to try to instantiate regular-sized pages in the
@@ -3141,6 +3148,7 @@ const struct vm_operations_struct hugetl
.fault = hugetlb_vm_op_fault,
.open = hugetlb_vm_op_open,
.close = hugetlb_vm_op_close,
+ .split = hugetlb_vm_op_split,
};
static pte_t make_huge_pte(struct vm_area_struct *vma, struct page *page,
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -2540,9 +2540,11 @@ int __split_vma(struct mm_struct *mm, st
struct vm_area_struct *new;
int err;
- if (is_vm_hugetlb_page(vma) && (addr &
- ~(huge_page_mask(hstate_vma(vma)))))
- return -EINVAL;
+ if (vma->vm_ops && vma->vm_ops->split) {
+ err = vma->vm_ops->split(vma, addr);
+ if (err)
+ return err;
+ }
new = kmem_cache_alloc(vm_area_cachep, GFP_KERNEL);
if (!new)
Patches currently in stable-queue which might be from dan.j.williams(a)intel.com are
queue-4.14/mm-hugetlbfs-introduce-split-to-vm_operations_struct.patch
queue-4.14/ib-core-disable-memory-registration-of-filesystem-dax-vmas.patch
queue-4.14/mm-introduce-get_user_pages_longterm.patch
queue-4.14/mm-fail-get_vaddr_frames-for-filesystem-dax-mappings.patch
queue-4.14/device-dax-implement-split-to-catch-invalid-munmap-attempts.patch
queue-4.14/v4l2-disable-filesystem-dax-mapping-support.patch
queue-4.14/mm-fix-device-dax-pud-write-faults-triggered-by-get_user_pages.patch
queue-4.14/mm-madvise.c-fix-madvise-infinite-loop-under-special-circumstances.patch
This is a note to let you know that I've just added the patch titled
mm/hugetlb: fix NULL-pointer dereference on 5-level paging machine
to the 4.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
mm-hugetlb-fix-null-pointer-dereference-on-5-level-paging-machine.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From f4f0a3d85b50a65a348e2b8635041d6b30f01deb Mon Sep 17 00:00:00 2001
From: "Kirill A. Shutemov" <kirill.shutemov(a)linux.intel.com>
Date: Wed, 29 Nov 2017 16:11:30 -0800
Subject: mm/hugetlb: fix NULL-pointer dereference on 5-level paging machine
From: Kirill A. Shutemov <kirill.shutemov(a)linux.intel.com>
commit f4f0a3d85b50a65a348e2b8635041d6b30f01deb upstream.
I made a mistake during converting hugetlb code to 5-level paging: in
huge_pte_alloc() we have to use p4d_alloc(), not p4d_offset().
Otherwise it leads to crash -- NULL-pointer dereference in pud_alloc()
if p4d table is not yet allocated.
It only can happen in 5-level paging mode. In 4-level paging mode
p4d_offset() always returns pgd, so we are fine.
Link: http://lkml.kernel.org/r/20171122121921.64822-1-kirill.shutemov@linux.intel…
Fixes: c2febafc6773 ("mm: convert generic code to 5-level paging")
Signed-off-by: Kirill A. Shutemov <kirill.shutemov(a)linux.intel.com>
Acked-by: Vlastimil Babka <vbabka(a)suse.cz>
Acked-by: Michal Hocko <mhocko(a)suse.com>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
mm/hugetlb.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -4625,7 +4625,9 @@ pte_t *huge_pte_alloc(struct mm_struct *
pte_t *pte = NULL;
pgd = pgd_offset(mm, addr);
- p4d = p4d_offset(pgd, addr);
+ p4d = p4d_alloc(mm, pgd, addr);
+ if (!p4d)
+ return NULL;
pud = pud_alloc(mm, p4d, addr);
if (pud) {
if (sz == PUD_SIZE) {
Patches currently in stable-queue which might be from kirill.shutemov(a)linux.intel.com are
queue-4.14/mm-fix-device-dax-pud-write-faults-triggered-by-get_user_pages.patch
queue-4.14/mm-hugetlb-fix-null-pointer-dereference-on-5-level-paging-machine.patch
queue-4.14/mm-thp-do-not-make-page-table-dirty-unconditionally-in-touch_pd.patch
queue-4.14/mm-madvise.c-fix-madvise-infinite-loop-under-special-circumstances.patch
This is a note to let you know that I've just added the patch titled
mm: fix device-dax pud write-faults triggered by get_user_pages()
to the 4.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
mm-fix-device-dax-pud-write-faults-triggered-by-get_user_pages.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From 1501899a898dfb5477c55534bdfd734c046da06d Mon Sep 17 00:00:00 2001
From: Dan Williams <dan.j.williams(a)intel.com>
Date: Wed, 29 Nov 2017 16:10:06 -0800
Subject: mm: fix device-dax pud write-faults triggered by get_user_pages()
From: Dan Williams <dan.j.williams(a)intel.com>
commit 1501899a898dfb5477c55534bdfd734c046da06d upstream.
Currently only get_user_pages_fast() can safely handle the writable gup
case due to its use of pud_access_permitted() to check whether the pud
entry is writable. In the gup slow path pud_write() is used instead of
pud_access_permitted() and to date it has been unimplemented, just calls
BUG_ON().
kernel BUG at ./include/linux/hugetlb.h:244!
[..]
RIP: 0010:follow_devmap_pud+0x482/0x490
[..]
Call Trace:
follow_page_mask+0x28c/0x6e0
__get_user_pages+0xe4/0x6c0
get_user_pages_unlocked+0x130/0x1b0
get_user_pages_fast+0x89/0xb0
iov_iter_get_pages_alloc+0x114/0x4a0
nfs_direct_read_schedule_iovec+0xd2/0x350
? nfs_start_io_direct+0x63/0x70
nfs_file_direct_read+0x1e0/0x250
nfs_file_read+0x90/0xc0
For now this just implements a simple check for the _PAGE_RW bit similar
to pmd_write. However, this implies that the gup-slow-path check is
missing the extra checks that the gup-fast-path performs with
pud_access_permitted. Later patches will align all checks to use the
'access_permitted' helper if the architecture provides it.
Note that the generic 'access_permitted' helper fallback is the simple
_PAGE_RW check on architectures that do not define the
'access_permitted' helper(s).
[dan.j.williams(a)intel.com: fix powerpc compile error]
Link: http://lkml.kernel.org/r/151129126165.37405.16031785266675461397.stgit@dwil…
Link: http://lkml.kernel.org/r/151043109938.2842.14834662818213616199.stgit@dwill…
Fixes: a00cc7d9dd93 ("mm, x86: add support for PUD-sized transparent hugepages")
Signed-off-by: Dan Williams <dan.j.williams(a)intel.com>
Reported-by: Stephen Rothwell <sfr(a)canb.auug.org.au>
Acked-by: Thomas Gleixner <tglx(a)linutronix.de> [x86]
Cc: Kirill A. Shutemov <kirill.shutemov(a)linux.intel.com>
Cc: Catalin Marinas <catalin.marinas(a)arm.com>
Cc: "David S. Miller" <davem(a)davemloft.net>
Cc: Dave Hansen <dave.hansen(a)intel.com>
Cc: Will Deacon <will.deacon(a)arm.com>
Cc: "H. Peter Anvin" <hpa(a)zytor.com>
Cc: Ingo Molnar <mingo(a)redhat.com>
Cc: Arnd Bergmann <arnd(a)arndb.de>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
arch/x86/include/asm/pgtable.h | 6 ++++++
include/asm-generic/pgtable.h | 8 ++++++++
include/linux/hugetlb.h | 8 --------
3 files changed, 14 insertions(+), 8 deletions(-)
--- a/arch/x86/include/asm/pgtable.h
+++ b/arch/x86/include/asm/pgtable.h
@@ -1093,6 +1093,12 @@ static inline void pmdp_set_wrprotect(st
clear_bit(_PAGE_BIT_RW, (unsigned long *)pmdp);
}
+#define pud_write pud_write
+static inline int pud_write(pud_t pud)
+{
+ return pud_flags(pud) & _PAGE_RW;
+}
+
/*
* clone_pgd_range(pgd_t *dst, pgd_t *src, int count);
*
--- a/include/asm-generic/pgtable.h
+++ b/include/asm-generic/pgtable.h
@@ -814,6 +814,14 @@ static inline int pmd_write(pmd_t pmd)
#endif /* __HAVE_ARCH_PMD_WRITE */
#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
+#ifndef pud_write
+static inline int pud_write(pud_t pud)
+{
+ BUG();
+ return 0;
+}
+#endif /* pud_write */
+
#if !defined(CONFIG_TRANSPARENT_HUGEPAGE) || \
(defined(CONFIG_TRANSPARENT_HUGEPAGE) && \
!defined(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD))
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -239,14 +239,6 @@ static inline int pgd_write(pgd_t pgd)
}
#endif
-#ifndef pud_write
-static inline int pud_write(pud_t pud)
-{
- BUG();
- return 0;
-}
-#endif
-
#define HUGETLB_ANON_FILE "anon_hugepage"
enum {
Patches currently in stable-queue which might be from dan.j.williams(a)intel.com are
queue-4.14/mm-hugetlbfs-introduce-split-to-vm_operations_struct.patch
queue-4.14/ib-core-disable-memory-registration-of-filesystem-dax-vmas.patch
queue-4.14/mm-introduce-get_user_pages_longterm.patch
queue-4.14/mm-fail-get_vaddr_frames-for-filesystem-dax-mappings.patch
queue-4.14/device-dax-implement-split-to-catch-invalid-munmap-attempts.patch
queue-4.14/v4l2-disable-filesystem-dax-mapping-support.patch
queue-4.14/mm-fix-device-dax-pud-write-faults-triggered-by-get_user_pages.patch
queue-4.14/mm-madvise.c-fix-madvise-infinite-loop-under-special-circumstances.patch
This is a note to let you know that I've just added the patch titled
mm: fail get_vaddr_frames() for filesystem-dax mappings
to the 4.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
mm-fail-get_vaddr_frames-for-filesystem-dax-mappings.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From b7f0554a56f21fb3e636a627450a9add030889be Mon Sep 17 00:00:00 2001
From: Dan Williams <dan.j.williams(a)intel.com>
Date: Wed, 29 Nov 2017 16:10:39 -0800
Subject: mm: fail get_vaddr_frames() for filesystem-dax mappings
From: Dan Williams <dan.j.williams(a)intel.com>
commit b7f0554a56f21fb3e636a627450a9add030889be upstream.
Until there is a solution to the dma-to-dax vs truncate problem it is
not safe to allow V4L2, Exynos, and other frame vector users to create
long standing / irrevocable memory registrations against filesytem-dax
vmas.
[dan.j.williams(a)intel.com: add comment for vma_is_fsdax() check in get_vaddr_frames(), per Jan]
Link: http://lkml.kernel.org/r/151197874035.26211.4061781453123083667.stgit@dwill…
Link: http://lkml.kernel.org/r/151068939985.7446.15684639617389154187.stgit@dwill…
Fixes: 3565fce3a659 ("mm, x86: get_user_pages() for dax mappings")
Signed-off-by: Dan Williams <dan.j.williams(a)intel.com>
Reviewed-by: Jan Kara <jack(a)suse.cz>
Cc: Inki Dae <inki.dae(a)samsung.com>
Cc: Seung-Woo Kim <sw0312.kim(a)samsung.com>
Cc: Joonyoung Shim <jy0922.shim(a)samsung.com>
Cc: Kyungmin Park <kyungmin.park(a)samsung.com>
Cc: Mauro Carvalho Chehab <mchehab(a)kernel.org>
Cc: Mel Gorman <mgorman(a)suse.de>
Cc: Vlastimil Babka <vbabka(a)suse.cz>
Cc: Christoph Hellwig <hch(a)lst.de>
Cc: Doug Ledford <dledford(a)redhat.com>
Cc: Hal Rosenstock <hal.rosenstock(a)gmail.com>
Cc: Jason Gunthorpe <jgg(a)mellanox.com>
Cc: Jeff Moyer <jmoyer(a)redhat.com>
Cc: Ross Zwisler <ross.zwisler(a)linux.intel.com>
Cc: Sean Hefty <sean.hefty(a)intel.com>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
mm/frame_vector.c | 12 ++++++++++++
1 file changed, 12 insertions(+)
--- a/mm/frame_vector.c
+++ b/mm/frame_vector.c
@@ -53,6 +53,18 @@ int get_vaddr_frames(unsigned long start
ret = -EFAULT;
goto out;
}
+
+ /*
+ * While get_vaddr_frames() could be used for transient (kernel
+ * controlled lifetime) pinning of memory pages all current
+ * users establish long term (userspace controlled lifetime)
+ * page pinning. Treat get_vaddr_frames() like
+ * get_user_pages_longterm() and disallow it for filesystem-dax
+ * mappings.
+ */
+ if (vma_is_fsdax(vma))
+ return -EOPNOTSUPP;
+
if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) {
vec->got_ref = true;
vec->is_pfns = false;
Patches currently in stable-queue which might be from dan.j.williams(a)intel.com are
queue-4.14/mm-hugetlbfs-introduce-split-to-vm_operations_struct.patch
queue-4.14/ib-core-disable-memory-registration-of-filesystem-dax-vmas.patch
queue-4.14/mm-introduce-get_user_pages_longterm.patch
queue-4.14/mm-fail-get_vaddr_frames-for-filesystem-dax-mappings.patch
queue-4.14/device-dax-implement-split-to-catch-invalid-munmap-attempts.patch
queue-4.14/v4l2-disable-filesystem-dax-mapping-support.patch
queue-4.14/mm-fix-device-dax-pud-write-faults-triggered-by-get_user_pages.patch
queue-4.14/mm-madvise.c-fix-madvise-infinite-loop-under-special-circumstances.patch
This is a note to let you know that I've just added the patch titled
mm/cma: fix alloc_contig_range ret code/potential leak
to the 4.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
mm-cma-fix-alloc_contig_range-ret-code-potential-leak.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From 63cd448908b5eb51d84c52f02b31b9b4ccd1cb5a Mon Sep 17 00:00:00 2001
From: Mike Kravetz <mike.kravetz(a)oracle.com>
Date: Wed, 29 Nov 2017 16:10:01 -0800
Subject: mm/cma: fix alloc_contig_range ret code/potential leak
From: Mike Kravetz <mike.kravetz(a)oracle.com>
commit 63cd448908b5eb51d84c52f02b31b9b4ccd1cb5a upstream.
If the call __alloc_contig_migrate_range() in alloc_contig_range returns
-EBUSY, processing continues so that test_pages_isolated() is called
where there is a tracepoint to identify the busy pages. However, it is
possible for busy pages to become available between the calls to these
two routines. In this case, the range of pages may be allocated.
Unfortunately, the original return code (ret == -EBUSY) is still set and
returned to the caller. Therefore, the caller believes the pages were
not allocated and they are leaked.
Update the comment to indicate that allocation is still possible even if
__alloc_contig_migrate_range returns -EBUSY. Also, clear return code in
this case so that it is not accidentally used or returned to caller.
Link: http://lkml.kernel.org/r/20171122185214.25285-1-mike.kravetz@oracle.com
Fixes: 8ef5849fa8a2 ("mm/cma: always check which page caused allocation failure")
Signed-off-by: Mike Kravetz <mike.kravetz(a)oracle.com>
Acked-by: Vlastimil Babka <vbabka(a)suse.cz>
Acked-by: Michal Hocko <mhocko(a)suse.com>
Acked-by: Johannes Weiner <hannes(a)cmpxchg.org>
Acked-by: Joonsoo Kim <iamjoonsoo.kim(a)lge.com>
Cc: Michal Nazarewicz <mina86(a)mina86.com>
Cc: Laura Abbott <labbott(a)redhat.com>
Cc: Michal Hocko <mhocko(a)suse.com>
Cc: Mel Gorman <mgorman(a)techsingularity.net>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
mm/page_alloc.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -7587,11 +7587,18 @@ int alloc_contig_range(unsigned long sta
/*
* In case of -EBUSY, we'd like to know which page causes problem.
- * So, just fall through. We will check it in test_pages_isolated().
+ * So, just fall through. test_pages_isolated() has a tracepoint
+ * which will report the busy page.
+ *
+ * It is possible that busy pages could become available before
+ * the call to test_pages_isolated, and the range will actually be
+ * allocated. So, if we fall through be sure to clear ret so that
+ * -EBUSY is not accidentally used or returned to caller.
*/
ret = __alloc_contig_migrate_range(&cc, start, end);
if (ret && ret != -EBUSY)
goto done;
+ ret =0;
/*
* Pages from [start, end) are within a MAX_ORDER_NR_PAGES
Patches currently in stable-queue which might be from mike.kravetz(a)oracle.com are
queue-4.14/mm-cma-fix-alloc_contig_range-ret-code-potential-leak.patch
This is a note to let you know that I've just added the patch titled
IB/core: disable memory registration of filesystem-dax vmas
to the 4.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
ib-core-disable-memory-registration-of-filesystem-dax-vmas.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From 5f1d43de54164dcfb9bfa542fcc92c1e1a1b6c1d Mon Sep 17 00:00:00 2001
From: Dan Williams <dan.j.williams(a)intel.com>
Date: Wed, 29 Nov 2017 16:10:47 -0800
Subject: IB/core: disable memory registration of filesystem-dax vmas
From: Dan Williams <dan.j.williams(a)intel.com>
commit 5f1d43de54164dcfb9bfa542fcc92c1e1a1b6c1d upstream.
Until there is a solution to the dma-to-dax vs truncate problem it is
not safe to allow RDMA to create long standing memory registrations
against filesytem-dax vmas.
Link: http://lkml.kernel.org/r/151068941011.7446.7766030590347262502.stgit@dwilli…
Fixes: 3565fce3a659 ("mm, x86: get_user_pages() for dax mappings")
Signed-off-by: Dan Williams <dan.j.williams(a)intel.com>
Reported-by: Christoph Hellwig <hch(a)lst.de>
Reviewed-by: Christoph Hellwig <hch(a)lst.de>
Acked-by: Jason Gunthorpe <jgg(a)mellanox.com>
Acked-by: Doug Ledford <dledford(a)redhat.com>
Cc: Sean Hefty <sean.hefty(a)intel.com>
Cc: Hal Rosenstock <hal.rosenstock(a)gmail.com>
Cc: Jeff Moyer <jmoyer(a)redhat.com>
Cc: Ross Zwisler <ross.zwisler(a)linux.intel.com>
Cc: Inki Dae <inki.dae(a)samsung.com>
Cc: Jan Kara <jack(a)suse.cz>
Cc: Joonyoung Shim <jy0922.shim(a)samsung.com>
Cc: Kyungmin Park <kyungmin.park(a)samsung.com>
Cc: Mauro Carvalho Chehab <mchehab(a)kernel.org>
Cc: Mel Gorman <mgorman(a)suse.de>
Cc: Seung-Woo Kim <sw0312.kim(a)samsung.com>
Cc: Vlastimil Babka <vbabka(a)suse.cz>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
drivers/infiniband/core/umem.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/infiniband/core/umem.c
+++ b/drivers/infiniband/core/umem.c
@@ -191,7 +191,7 @@ struct ib_umem *ib_umem_get(struct ib_uc
sg_list_start = umem->sg_head.sgl;
while (npages) {
- ret = get_user_pages(cur_base,
+ ret = get_user_pages_longterm(cur_base,
min_t(unsigned long, npages,
PAGE_SIZE / sizeof (struct page *)),
gup_flags, page_list, vma_list);
Patches currently in stable-queue which might be from dan.j.williams(a)intel.com are
queue-4.14/mm-hugetlbfs-introduce-split-to-vm_operations_struct.patch
queue-4.14/ib-core-disable-memory-registration-of-filesystem-dax-vmas.patch
queue-4.14/mm-introduce-get_user_pages_longterm.patch
queue-4.14/mm-fail-get_vaddr_frames-for-filesystem-dax-mappings.patch
queue-4.14/device-dax-implement-split-to-catch-invalid-munmap-attempts.patch
queue-4.14/v4l2-disable-filesystem-dax-mapping-support.patch
queue-4.14/mm-fix-device-dax-pud-write-faults-triggered-by-get_user_pages.patch
queue-4.14/mm-madvise.c-fix-madvise-infinite-loop-under-special-circumstances.patch
This is a note to let you know that I've just added the patch titled
fs/fat/inode.c: fix sb_rdonly() change
to the 4.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
fs-fat-inode.c-fix-sb_rdonly-change.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From b6e8e12c0aeb5fbf1bf46c84d58cc93aedede385 Mon Sep 17 00:00:00 2001
From: OGAWA Hirofumi <hirofumi(a)mail.parknet.co.jp>
Date: Wed, 29 Nov 2017 16:11:19 -0800
Subject: fs/fat/inode.c: fix sb_rdonly() change
From: OGAWA Hirofumi <hirofumi(a)mail.parknet.co.jp>
commit b6e8e12c0aeb5fbf1bf46c84d58cc93aedede385 upstream.
Commit bc98a42c1f7d ("VFS: Convert sb->s_flags & MS_RDONLY to
sb_rdonly(sb)") converted fat_remount():new_rdonly from a bool to an
int.
However fat_remount() depends upon the compiler's conversion of a
non-zero integer into boolean `true'.
Fix it by switching `new_rdonly' back into a bool.
Link: http://lkml.kernel.org/r/87mv3d5x51.fsf@mail.parknet.co.jp
Fixes: bc98a42c1f7d0f8 ("VFS: Convert sb->s_flags & MS_RDONLY to sb_rdonly(sb)")
Signed-off-by: OGAWA Hirofumi <hirofumi(a)mail.parknet.co.jp>
Cc: Joe Perches <joe(a)perches.com>
Cc: David Howells <dhowells(a)redhat.com>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
fs/fat/inode.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/fs/fat/inode.c
+++ b/fs/fat/inode.c
@@ -779,7 +779,7 @@ static void __exit fat_destroy_inodecach
static int fat_remount(struct super_block *sb, int *flags, char *data)
{
- int new_rdonly;
+ bool new_rdonly;
struct msdos_sb_info *sbi = MSDOS_SB(sb);
*flags |= MS_NODIRATIME | (sbi->options.isvfat ? 0 : MS_NOATIME);
Patches currently in stable-queue which might be from hirofumi(a)mail.parknet.co.jp are
queue-4.14/fs-fat-inode.c-fix-sb_rdonly-change.patch
This is a note to let you know that I've just added the patch titled
exec: avoid RLIMIT_STACK races with prlimit()
to the 4.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
exec-avoid-rlimit_stack-races-with-prlimit.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From 04e35f4495dd560db30c25efca4eecae8ec8c375 Mon Sep 17 00:00:00 2001
From: Kees Cook <keescook(a)chromium.org>
Date: Wed, 29 Nov 2017 16:10:51 -0800
Subject: exec: avoid RLIMIT_STACK races with prlimit()
From: Kees Cook <keescook(a)chromium.org>
commit 04e35f4495dd560db30c25efca4eecae8ec8c375 upstream.
While the defense-in-depth RLIMIT_STACK limit on setuid processes was
protected against races from other threads calling setrlimit(), I missed
protecting it against races from external processes calling prlimit().
This adds locking around the change and makes sure that rlim_max is set
too.
Link: http://lkml.kernel.org/r/20171127193457.GA11348@beast
Fixes: 64701dee4178e ("exec: Use sane stack rlimit under secureexec")
Signed-off-by: Kees Cook <keescook(a)chromium.org>
Reported-by: Ben Hutchings <ben.hutchings(a)codethink.co.uk>
Reported-by: Brad Spengler <spender(a)grsecurity.net>
Acked-by: Serge Hallyn <serge(a)hallyn.com>
Cc: James Morris <james.l.morris(a)oracle.com>
Cc: Andy Lutomirski <luto(a)kernel.org>
Cc: Oleg Nesterov <oleg(a)redhat.com>
Cc: Jiri Slaby <jslaby(a)suse.cz>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
fs/exec.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -1340,10 +1340,15 @@ void setup_new_exec(struct linux_binprm
* avoid bad behavior from the prior rlimits. This has to
* happen before arch_pick_mmap_layout(), which examines
* RLIMIT_STACK, but after the point of no return to avoid
- * needing to clean up the change on failure.
+ * races from other threads changing the limits. This also
+ * must be protected from races with prlimit() calls.
*/
+ task_lock(current->group_leader);
if (current->signal->rlim[RLIMIT_STACK].rlim_cur > _STK_LIM)
current->signal->rlim[RLIMIT_STACK].rlim_cur = _STK_LIM;
+ if (current->signal->rlim[RLIMIT_STACK].rlim_max > _STK_LIM)
+ current->signal->rlim[RLIMIT_STACK].rlim_max = _STK_LIM;
+ task_unlock(current->group_leader);
}
arch_pick_mmap_layout(current->mm);
Patches currently in stable-queue which might be from keescook(a)chromium.org are
queue-4.14/exec-avoid-rlimit_stack-races-with-prlimit.patch
This is a note to let you know that I've just added the patch titled
device-dax: implement ->split() to catch invalid munmap attempts
to the 4.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
device-dax-implement-split-to-catch-invalid-munmap-attempts.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From 9702cffdbf2129516db679e4467db81e1cd287da Mon Sep 17 00:00:00 2001
From: Dan Williams <dan.j.williams(a)intel.com>
Date: Wed, 29 Nov 2017 16:10:32 -0800
Subject: device-dax: implement ->split() to catch invalid munmap attempts
From: Dan Williams <dan.j.williams(a)intel.com>
commit 9702cffdbf2129516db679e4467db81e1cd287da upstream.
Similar to how device-dax enforces that the 'address', 'offset', and
'len' parameters to mmap() be aligned to the device's fundamental
alignment, the same constraints apply to munmap(). Implement ->split()
to fail munmap calls that violate the alignment constraint.
Otherwise, we later fail VM_BUG_ON checks in the unmap_page_range() path
with crash signatures of the form:
vma ffff8800b60c8a88 start 00007f88c0000000 end 00007f88c0e00000
next (null) prev (null) mm ffff8800b61150c0
prot 8000000000000027 anon_vma (null) vm_ops ffffffffa0091240
pgoff 0 file ffff8800b638ef80 private_data (null)
flags: 0x380000fb(read|write|shared|mayread|maywrite|mayexec|mayshare|softdirty|mixedmap|hugepage)
------------[ cut here ]------------
kernel BUG at mm/huge_memory.c:2014!
[..]
RIP: 0010:__split_huge_pud+0x12a/0x180
[..]
Call Trace:
unmap_page_range+0x245/0xa40
? __vma_adjust+0x301/0x990
unmap_vmas+0x4c/0xa0
unmap_region+0xae/0x120
? __vma_rb_erase+0x11a/0x230
do_munmap+0x276/0x410
vm_munmap+0x6a/0xa0
SyS_munmap+0x1d/0x30
Link: http://lkml.kernel.org/r/151130418681.4029.7118245855057952010.stgit@dwilli…
Fixes: dee410792419 ("/dev/dax, core: file operations and dax-mmap")
Signed-off-by: Dan Williams <dan.j.williams(a)intel.com>
Reported-by: Jeff Moyer <jmoyer(a)redhat.com>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
drivers/dax/device.c | 12 ++++++++++++
1 file changed, 12 insertions(+)
--- a/drivers/dax/device.c
+++ b/drivers/dax/device.c
@@ -427,9 +427,21 @@ static int dev_dax_fault(struct vm_fault
return dev_dax_huge_fault(vmf, PE_SIZE_PTE);
}
+static int dev_dax_split(struct vm_area_struct *vma, unsigned long addr)
+{
+ struct file *filp = vma->vm_file;
+ struct dev_dax *dev_dax = filp->private_data;
+ struct dax_region *dax_region = dev_dax->region;
+
+ if (!IS_ALIGNED(addr, dax_region->align))
+ return -EINVAL;
+ return 0;
+}
+
static const struct vm_operations_struct dax_vm_ops = {
.fault = dev_dax_fault,
.huge_fault = dev_dax_huge_fault,
+ .split = dev_dax_split,
};
static int dax_mmap(struct file *filp, struct vm_area_struct *vma)
Patches currently in stable-queue which might be from dan.j.williams(a)intel.com are
queue-4.14/mm-hugetlbfs-introduce-split-to-vm_operations_struct.patch
queue-4.14/ib-core-disable-memory-registration-of-filesystem-dax-vmas.patch
queue-4.14/mm-introduce-get_user_pages_longterm.patch
queue-4.14/mm-fail-get_vaddr_frames-for-filesystem-dax-mappings.patch
queue-4.14/device-dax-implement-split-to-catch-invalid-munmap-attempts.patch
queue-4.14/v4l2-disable-filesystem-dax-mapping-support.patch
queue-4.14/mm-fix-device-dax-pud-write-faults-triggered-by-get_user_pages.patch
queue-4.14/mm-madvise.c-fix-madvise-infinite-loop-under-special-circumstances.patch
This is a note to let you know that I've just added the patch titled
autofs: revert "autofs: take more care to not update last_used on path walk"
to the 4.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
autofs-revert-autofs-take-more-care-to-not-update-last_used-on-path-walk.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From 43694d4bf843ddd34519e8e9de983deefeada699 Mon Sep 17 00:00:00 2001
From: Ian Kent <raven(a)themaw.net>
Date: Wed, 29 Nov 2017 16:11:23 -0800
Subject: autofs: revert "autofs: take more care to not update last_used on path walk"
From: Ian Kent <raven(a)themaw.net>
commit 43694d4bf843ddd34519e8e9de983deefeada699 upstream.
While commit 092a53452bb7 ("autofs: take more care to not update
last_used on path walk") helped (partially) resolve a problem where
automounts were not expiring due to aggressive accesses from user space
it has a side effect for very large environments.
This change helps with the expire problem by making the expire more
aggressive but, for very large environments, that means more mount
requests from clients. When there are a lot of clients that can mean
fairly significant server load increases.
It turns out I put the last_used in this position to solve this very
problem and failed to update my own thinking of the autofs expire
policy. So the patch being reverted introduces a regression which
should be fixed.
Link: http://lkml.kernel.org/r/151174729420.6162.1832622523537052460.stgit@pluto.…
Fixes: 092a53452b ("autofs: take more care to not update last_used on path walk")
Signed-off-by: Ian Kent <raven(a)themaw.net>
Reviewed-by: NeilBrown <neilb(a)suse.com>
Cc: Al Viro <viro(a)ZenIV.linux.org.uk>
Cc: Colin Walters <walters(a)redhat.com>
Cc: David Howells <dhowells(a)redhat.com>
Cc: Ondrej Holy <oholy(a)redhat.com>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
fs/autofs4/root.c | 17 ++++++-----------
1 file changed, 6 insertions(+), 11 deletions(-)
--- a/fs/autofs4/root.c
+++ b/fs/autofs4/root.c
@@ -281,8 +281,8 @@ static int autofs4_mount_wait(const stru
pr_debug("waiting for mount name=%pd\n", path->dentry);
status = autofs4_wait(sbi, path, NFY_MOUNT);
pr_debug("mount wait done status=%d\n", status);
- ino->last_used = jiffies;
}
+ ino->last_used = jiffies;
return status;
}
@@ -321,21 +321,16 @@ static struct dentry *autofs4_mountpoint
*/
if (autofs_type_indirect(sbi->type) && d_unhashed(dentry)) {
struct dentry *parent = dentry->d_parent;
+ struct autofs_info *ino;
struct dentry *new;
new = d_lookup(parent, &dentry->d_name);
if (!new)
return NULL;
- if (new == dentry)
- dput(new);
- else {
- struct autofs_info *ino;
-
- ino = autofs4_dentry_ino(new);
- ino->last_used = jiffies;
- dput(path->dentry);
- path->dentry = new;
- }
+ ino = autofs4_dentry_ino(new);
+ ino->last_used = jiffies;
+ dput(path->dentry);
+ path->dentry = new;
}
return path->dentry;
}
Patches currently in stable-queue which might be from raven(a)themaw.net are
queue-4.14/autofs-revert-autofs-fix-at_no_automount-not-being-honored.patch
queue-4.14/autofs-revert-autofs-take-more-care-to-not-update-last_used-on-path-walk.patch
This is a note to let you know that I've just added the patch titled
autofs: revert "autofs: fix AT_NO_AUTOMOUNT not being honored"
to the 4.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
autofs-revert-autofs-fix-at_no_automount-not-being-honored.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From 5d38f049cee1e1c4a7ac55aa79d37d01ddcc3860 Mon Sep 17 00:00:00 2001
From: Ian Kent <raven(a)themaw.net>
Date: Wed, 29 Nov 2017 16:11:26 -0800
Subject: autofs: revert "autofs: fix AT_NO_AUTOMOUNT not being honored"
From: Ian Kent <raven(a)themaw.net>
commit 5d38f049cee1e1c4a7ac55aa79d37d01ddcc3860 upstream.
Commit 42f461482178 ("autofs: fix AT_NO_AUTOMOUNT not being honored")
allowed the fstatat(2) system call to properly honor the AT_NO_AUTOMOUNT
flag but introduced a semantic change.
In order to honor AT_NO_AUTOMOUNT a semantic change was made to the
negative dentry case for stat family system calls in follow_automount().
This changed the unconditional triggering of an automount in this case
to no longer be done and an error returned instead.
This has caused more problems than I expected so reverting the change is
needed.
In a discussion with Neil Brown it was concluded that the automount(8)
daemon can implement this change without kernel modifications. So that
will be done instead and the autofs module documentation updated with a
description of the problem and what needs to be done by module users for
this specific case.
Link: http://lkml.kernel.org/r/151174730120.6162.3848002191530283984.stgit@pluto.…
Fixes: 42f4614821 ("autofs: fix AT_NO_AUTOMOUNT not being honored")
Signed-off-by: Ian Kent <raven(a)themaw.net>
Cc: Neil Brown <neilb(a)suse.com>
Cc: Al Viro <viro(a)ZenIV.linux.org.uk>
Cc: David Howells <dhowells(a)redhat.com>
Cc: Colin Walters <walters(a)redhat.com>
Cc: Ondrej Holy <oholy(a)redhat.com>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
fs/namei.c | 15 +++------------
include/linux/fs.h | 3 ++-
2 files changed, 5 insertions(+), 13 deletions(-)
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -1129,18 +1129,9 @@ static int follow_automount(struct path
* of the daemon to instantiate them before they can be used.
*/
if (!(nd->flags & (LOOKUP_PARENT | LOOKUP_DIRECTORY |
- LOOKUP_OPEN | LOOKUP_CREATE |
- LOOKUP_AUTOMOUNT))) {
- /* Positive dentry that isn't meant to trigger an
- * automount, EISDIR will allow it to be used,
- * otherwise there's no mount here "now" so return
- * ENOENT.
- */
- if (path->dentry->d_inode)
- return -EISDIR;
- else
- return -ENOENT;
- }
+ LOOKUP_OPEN | LOOKUP_CREATE | LOOKUP_AUTOMOUNT)) &&
+ path->dentry->d_inode)
+ return -EISDIR;
if (path->dentry->d_sb->s_user_ns != &init_user_ns)
return -EACCES;
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -3069,7 +3069,8 @@ static inline int vfs_lstat(const char _
static inline int vfs_fstatat(int dfd, const char __user *filename,
struct kstat *stat, int flags)
{
- return vfs_statx(dfd, filename, flags, stat, STATX_BASIC_STATS);
+ return vfs_statx(dfd, filename, flags | AT_NO_AUTOMOUNT,
+ stat, STATX_BASIC_STATS);
}
static inline int vfs_fstat(int fd, struct kstat *stat)
{
Patches currently in stable-queue which might be from raven(a)themaw.net are
queue-4.14/autofs-revert-autofs-fix-at_no_automount-not-being-honored.patch
queue-4.14/autofs-revert-autofs-take-more-care-to-not-update-last_used-on-path-walk.patch
This is a note to let you know that I've just added the patch titled
mm, thp: Do not make page table dirty unconditionally in touch_p[mu]d()
to the 3.18-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
mm-thp-do-not-make-page-table-dirty-unconditionally-in-touch_pd.patch
and it can be found in the queue-3.18 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From a8f97366452ed491d13cf1e44241bc0b5740b1f0 Mon Sep 17 00:00:00 2001
From: "Kirill A. Shutemov" <kirill.shutemov(a)linux.intel.com>
Date: Mon, 27 Nov 2017 06:21:25 +0300
Subject: mm, thp: Do not make page table dirty unconditionally in touch_p[mu]d()
From: Kirill A. Shutemov <kirill.shutemov(a)linux.intel.com>
commit a8f97366452ed491d13cf1e44241bc0b5740b1f0 upstream.
Currently, we unconditionally make page table dirty in touch_pmd().
It may result in false-positive can_follow_write_pmd().
We may avoid the situation, if we would only make the page table entry
dirty if caller asks for write access -- FOLL_WRITE.
The patch also changes touch_pud() in the same way.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov(a)linux.intel.com>
Cc: Michal Hocko <mhocko(a)suse.com>
Cc: Hugh Dickins <hughd(a)google.com>
Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org>
[Salvatore Bonaccorso: backport for 3.16:
- Adjust context
- Drop specific part for PUD-sized transparent hugepages. Support
for PUD-sized transparent hugepages was added in v4.11-rc1
]
Signed-off-by: Ben Hutchings <ben(a)decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
mm/huge_memory.c | 14 ++++----------
1 file changed, 4 insertions(+), 10 deletions(-)
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -1240,17 +1240,11 @@ struct page *follow_trans_huge_pmd(struc
VM_BUG_ON_PAGE(!PageHead(page), page);
if (flags & FOLL_TOUCH) {
pmd_t _pmd;
- /*
- * We should set the dirty bit only for FOLL_WRITE but
- * for now the dirty bit in the pmd is meaningless.
- * And if the dirty bit will become meaningful and
- * we'll only set it with FOLL_WRITE, an atomic
- * set_bit will be required on the pmd to set the
- * young bit, instead of the current set_pmd_at.
- */
- _pmd = pmd_mkyoung(pmd_mkdirty(*pmd));
+ _pmd = pmd_mkyoung(*pmd);
+ if (flags & FOLL_WRITE)
+ _pmd = pmd_mkdirty(_pmd);
if (pmdp_set_access_flags(vma, addr & HPAGE_PMD_MASK,
- pmd, _pmd, 1))
+ pmd, _pmd, flags & FOLL_WRITE))
update_mmu_cache_pmd(vma, addr, pmd);
}
if ((flags & FOLL_MLOCK) && (vma->vm_flags & VM_LOCKED)) {
Patches currently in stable-queue which might be from kirill.shutemov(a)linux.intel.com are
queue-3.18/mm-thp-do-not-make-page-table-dirty-unconditionally-in-touch_pd.patch
queue-3.18/mm-madvise.c-fix-madvise-infinite-loop-under-special-circumstances.patch
This is a note to let you know that I've just added the patch titled
mm/madvise.c: fix madvise() infinite loop under special circumstances
to the 3.18-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
mm-madvise.c-fix-madvise-infinite-loop-under-special-circumstances.patch
and it can be found in the queue-3.18 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From 6ea8d958a2c95a1d514015d4e29ba21a8c0a1a91 Mon Sep 17 00:00:00 2001
From: chenjie <chenjie6(a)huawei.com>
Date: Wed, 29 Nov 2017 16:10:54 -0800
Subject: mm/madvise.c: fix madvise() infinite loop under special circumstances
From: chenjie <chenjie6(a)huawei.com>
commit 6ea8d958a2c95a1d514015d4e29ba21a8c0a1a91 upstream.
MADVISE_WILLNEED has always been a noop for DAX (formerly XIP) mappings.
Unfortunately madvise_willneed() doesn't communicate this information
properly to the generic madvise syscall implementation. The calling
convention is quite subtle there. madvise_vma() is supposed to either
return an error or update &prev otherwise the main loop will never
advance to the next vma and it will keep looping for ever without a way
to get out of the kernel.
It seems this has been broken since introduction. Nobody has noticed
because nobody seems to be using MADVISE_WILLNEED on these DAX mappings.
[mhocko(a)suse.com: rewrite changelog]
Link: http://lkml.kernel.org/r/20171127115318.911-1-guoxuenan@huawei.com
Fixes: fe77ba6f4f97 ("[PATCH] xip: madvice/fadvice: execute in place")
Signed-off-by: chenjie <chenjie6(a)huawei.com>
Signed-off-by: guoxuenan <guoxuenan(a)huawei.com>
Acked-by: Michal Hocko <mhocko(a)suse.com>
Cc: Minchan Kim <minchan(a)kernel.org>
Cc: zhangyi (F) <yi.zhang(a)huawei.com>
Cc: Miao Xie <miaoxie(a)huawei.com>
Cc: Mike Rapoport <rppt(a)linux.vnet.ibm.com>
Cc: Shaohua Li <shli(a)fb.com>
Cc: Andrea Arcangeli <aarcange(a)redhat.com>
Cc: Mel Gorman <mgorman(a)techsingularity.net>
Cc: Kirill A. Shutemov <kirill.shutemov(a)linux.intel.com>
Cc: David Rientjes <rientjes(a)google.com>
Cc: Anshuman Khandual <khandual(a)linux.vnet.ibm.com>
Cc: Rik van Riel <riel(a)redhat.com>
Cc: Carsten Otte <cotte(a)de.ibm.com>
Cc: Dan Williams <dan.j.williams(a)intel.com>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
mm/madvise.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
--- a/mm/madvise.c
+++ b/mm/madvise.c
@@ -221,9 +221,9 @@ static long madvise_willneed(struct vm_a
{
struct file *file = vma->vm_file;
+ *prev = vma;
#ifdef CONFIG_SWAP
if (!file || mapping_cap_swap_backed(file->f_mapping)) {
- *prev = vma;
if (!file)
force_swapin_readahead(vma, start, end);
else
@@ -241,7 +241,6 @@ static long madvise_willneed(struct vm_a
return 0;
}
- *prev = vma;
start = ((start - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
if (end > vma->vm_end)
end = vma->vm_end;
Patches currently in stable-queue which might be from chenjie6(a)huawei.com are
queue-3.18/mm-madvise.c-fix-madvise-infinite-loop-under-special-circumstances.patch
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>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 5f1d43de54164dcfb9bfa542fcc92c1e1a1b6c1d Mon Sep 17 00:00:00 2001
From: Dan Williams <dan.j.williams(a)intel.com>
Date: Wed, 29 Nov 2017 16:10:47 -0800
Subject: [PATCH] IB/core: disable memory registration of filesystem-dax vmas
Until there is a solution to the dma-to-dax vs truncate problem it is
not safe to allow RDMA to create long standing memory registrations
against filesytem-dax vmas.
Link: http://lkml.kernel.org/r/151068941011.7446.7766030590347262502.stgit@dwilli…
Fixes: 3565fce3a659 ("mm, x86: get_user_pages() for dax mappings")
Signed-off-by: Dan Williams <dan.j.williams(a)intel.com>
Reported-by: Christoph Hellwig <hch(a)lst.de>
Reviewed-by: Christoph Hellwig <hch(a)lst.de>
Acked-by: Jason Gunthorpe <jgg(a)mellanox.com>
Acked-by: Doug Ledford <dledford(a)redhat.com>
Cc: Sean Hefty <sean.hefty(a)intel.com>
Cc: Hal Rosenstock <hal.rosenstock(a)gmail.com>
Cc: Jeff Moyer <jmoyer(a)redhat.com>
Cc: Ross Zwisler <ross.zwisler(a)linux.intel.com>
Cc: Inki Dae <inki.dae(a)samsung.com>
Cc: Jan Kara <jack(a)suse.cz>
Cc: Joonyoung Shim <jy0922.shim(a)samsung.com>
Cc: Kyungmin Park <kyungmin.park(a)samsung.com>
Cc: Mauro Carvalho Chehab <mchehab(a)kernel.org>
Cc: Mel Gorman <mgorman(a)suse.de>
Cc: Seung-Woo Kim <sw0312.kim(a)samsung.com>
Cc: Vlastimil Babka <vbabka(a)suse.cz>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org>
diff --git a/drivers/infiniband/core/umem.c b/drivers/infiniband/core/umem.c
index 21e60b1e2ff4..130606c3b07c 100644
--- a/drivers/infiniband/core/umem.c
+++ b/drivers/infiniband/core/umem.c
@@ -191,7 +191,7 @@ struct ib_umem *ib_umem_get(struct ib_ucontext *context, unsigned long addr,
sg_list_start = umem->sg_head.sgl;
while (npages) {
- ret = get_user_pages(cur_base,
+ ret = get_user_pages_longterm(cur_base,
min_t(unsigned long, npages,
PAGE_SIZE / sizeof (struct page *)),
gup_flags, page_list, vma_list);
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>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From b70131de648c2b997d22f4653934438013f407a1 Mon Sep 17 00:00:00 2001
From: Dan Williams <dan.j.williams(a)intel.com>
Date: Wed, 29 Nov 2017 16:10:43 -0800
Subject: [PATCH] v4l2: disable filesystem-dax mapping support
V4L2 memory registrations are incompatible with filesystem-dax that
needs the ability to revoke dma access to a mapping at will, or
otherwise allow the kernel to wait for completion of DMA. The
filesystem-dax implementation breaks the traditional solution of
truncate of active file backed mappings since there is no page-cache
page we can orphan to sustain ongoing DMA.
If v4l2 wants to support long lived DMA mappings it needs to arrange to
hold a file lease or use some other mechanism so that the kernel can
coordinate revoking DMA access when the filesystem needs to truncate
mappings.
Link: http://lkml.kernel.org/r/151068940499.7446.12846708245365671207.stgit@dwill…
Fixes: 3565fce3a659 ("mm, x86: get_user_pages() for dax mappings")
Signed-off-by: Dan Williams <dan.j.williams(a)intel.com>
Reported-by: Jan Kara <jack(a)suse.cz>
Reviewed-by: Jan Kara <jack(a)suse.cz>
Cc: Mauro Carvalho Chehab <mchehab(a)kernel.org>
Cc: Christoph Hellwig <hch(a)lst.de>
Cc: Doug Ledford <dledford(a)redhat.com>
Cc: Hal Rosenstock <hal.rosenstock(a)gmail.com>
Cc: Inki Dae <inki.dae(a)samsung.com>
Cc: Jason Gunthorpe <jgg(a)mellanox.com>
Cc: Jeff Moyer <jmoyer(a)redhat.com>
Cc: Joonyoung Shim <jy0922.shim(a)samsung.com>
Cc: Kyungmin Park <kyungmin.park(a)samsung.com>
Cc: Mel Gorman <mgorman(a)suse.de>
Cc: Ross Zwisler <ross.zwisler(a)linux.intel.com>
Cc: Sean Hefty <sean.hefty(a)intel.com>
Cc: Seung-Woo Kim <sw0312.kim(a)samsung.com>
Cc: Vlastimil Babka <vbabka(a)suse.cz>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org>
diff --git a/drivers/media/v4l2-core/videobuf-dma-sg.c b/drivers/media/v4l2-core/videobuf-dma-sg.c
index 0b5c43f7e020..f412429cf5ba 100644
--- a/drivers/media/v4l2-core/videobuf-dma-sg.c
+++ b/drivers/media/v4l2-core/videobuf-dma-sg.c
@@ -185,12 +185,13 @@ static int videobuf_dma_init_user_locked(struct videobuf_dmabuf *dma,
dprintk(1, "init user [0x%lx+0x%lx => %d pages]\n",
data, size, dma->nr_pages);
- err = get_user_pages(data & PAGE_MASK, dma->nr_pages,
+ err = get_user_pages_longterm(data & PAGE_MASK, dma->nr_pages,
flags, dma->pages, NULL);
if (err != dma->nr_pages) {
dma->nr_pages = (err >= 0) ? err : 0;
- dprintk(1, "get_user_pages: err=%d [%d]\n", err, dma->nr_pages);
+ dprintk(1, "get_user_pages_longterm: err=%d [%d]\n", err,
+ dma->nr_pages);
return err < 0 ? err : -EINVAL;
}
return 0;
Hi,
This patch series fixes the out-of-bound error caused by the return value
of usb_string(). It was descovered by KASAN. The Patch 1 is the V2 about
http://www.spinics.net/lists/alsa-devel/msg69487.html
Chanes in V2:
- put an explicit error bail out(by Takashi iwai)
Patch1 was founded by connecting the following product.
http://www.lg.com/uk/lg-friends/lg-AFD-1200
I found that it only check if the return value from usb_string() is always
zero while modifying OOB KASAN message. So instead of making the
modifications to OOB to V2, I sent a patch series.
I am sorry to break the mail thread.
Thanks
jaejoong
Jaejoong Kim (3):
ALSA: usb-audio: Fix out-of-bound error
ALSA: usb-audio: Fix return value check for usb_string()
ALSA: usb-audio: Add check return value for usb_string()
sound/usb/mixer.c | 41 ++++++++++++++++++++++++-----------------
1 file changed, 24 insertions(+), 17 deletions(-)
--
2.7.4
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>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From b7f0554a56f21fb3e636a627450a9add030889be Mon Sep 17 00:00:00 2001
From: Dan Williams <dan.j.williams(a)intel.com>
Date: Wed, 29 Nov 2017 16:10:39 -0800
Subject: [PATCH] mm: fail get_vaddr_frames() for filesystem-dax mappings
Until there is a solution to the dma-to-dax vs truncate problem it is
not safe to allow V4L2, Exynos, and other frame vector users to create
long standing / irrevocable memory registrations against filesytem-dax
vmas.
[dan.j.williams(a)intel.com: add comment for vma_is_fsdax() check in get_vaddr_frames(), per Jan]
Link: http://lkml.kernel.org/r/151197874035.26211.4061781453123083667.stgit@dwill…
Link: http://lkml.kernel.org/r/151068939985.7446.15684639617389154187.stgit@dwill…
Fixes: 3565fce3a659 ("mm, x86: get_user_pages() for dax mappings")
Signed-off-by: Dan Williams <dan.j.williams(a)intel.com>
Reviewed-by: Jan Kara <jack(a)suse.cz>
Cc: Inki Dae <inki.dae(a)samsung.com>
Cc: Seung-Woo Kim <sw0312.kim(a)samsung.com>
Cc: Joonyoung Shim <jy0922.shim(a)samsung.com>
Cc: Kyungmin Park <kyungmin.park(a)samsung.com>
Cc: Mauro Carvalho Chehab <mchehab(a)kernel.org>
Cc: Mel Gorman <mgorman(a)suse.de>
Cc: Vlastimil Babka <vbabka(a)suse.cz>
Cc: Christoph Hellwig <hch(a)lst.de>
Cc: Doug Ledford <dledford(a)redhat.com>
Cc: Hal Rosenstock <hal.rosenstock(a)gmail.com>
Cc: Jason Gunthorpe <jgg(a)mellanox.com>
Cc: Jeff Moyer <jmoyer(a)redhat.com>
Cc: Ross Zwisler <ross.zwisler(a)linux.intel.com>
Cc: Sean Hefty <sean.hefty(a)intel.com>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org>
diff --git a/mm/frame_vector.c b/mm/frame_vector.c
index 2f98df0d460e..297c7238f7d4 100644
--- a/mm/frame_vector.c
+++ b/mm/frame_vector.c
@@ -53,6 +53,18 @@ int get_vaddr_frames(unsigned long start, unsigned int nr_frames,
ret = -EFAULT;
goto out;
}
+
+ /*
+ * While get_vaddr_frames() could be used for transient (kernel
+ * controlled lifetime) pinning of memory pages all current
+ * users establish long term (userspace controlled lifetime)
+ * page pinning. Treat get_vaddr_frames() like
+ * get_user_pages_longterm() and disallow it for filesystem-dax
+ * mappings.
+ */
+ if (vma_is_fsdax(vma))
+ return -EOPNOTSUPP;
+
if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) {
vec->got_ref = true;
vec->is_pfns = false;
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>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 2bb6d2837083de722bfdc369cb0d76ce188dd9b4 Mon Sep 17 00:00:00 2001
From: Dan Williams <dan.j.williams(a)intel.com>
Date: Wed, 29 Nov 2017 16:10:35 -0800
Subject: [PATCH] mm: introduce get_user_pages_longterm
Patch series "introduce get_user_pages_longterm()", v2.
Here is a new get_user_pages api for cases where a driver intends to
keep an elevated page count indefinitely. This is distinct from usages
like iov_iter_get_pages where the elevated page counts are transient.
The iov_iter_get_pages cases immediately turn around and submit the
pages to a device driver which will put_page when the i/o operation
completes (under kernel control).
In the longterm case userspace is responsible for dropping the page
reference at some undefined point in the future. This is untenable for
filesystem-dax case where the filesystem is in control of the lifetime
of the block / page and needs reasonable limits on how long it can wait
for pages in a mapping to become idle.
Fixing filesystems to actually wait for dax pages to be idle before
blocks from a truncate/hole-punch operation are repurposed is saved for
a later patch series.
Also, allowing longterm registration of dax mappings is a future patch
series that introduces a "map with lease" semantic where the kernel can
revoke a lease and force userspace to drop its page references.
I have also tagged these for -stable to purposely break cases that might
assume that longterm memory registrations for filesystem-dax mappings
were supported by the kernel. The behavior regression this policy
change implies is one of the reasons we maintain the "dax enabled.
Warning: EXPERIMENTAL, use at your own risk" notification when mounting
a filesystem in dax mode.
It is worth noting the device-dax interface does not suffer the same
constraints since it does not support file space management operations
like hole-punch.
This patch (of 4):
Until there is a solution to the dma-to-dax vs truncate problem it is
not safe to allow long standing memory registrations against
filesytem-dax vmas. Device-dax vmas do not have this problem and are
explicitly allowed.
This is temporary until a "memory registration with layout-lease"
mechanism can be implemented for the affected sub-systems (RDMA and
V4L2).
[akpm(a)linux-foundation.org: use kcalloc()]
Link: http://lkml.kernel.org/r/151068939435.7446.13560129395419350737.stgit@dwill…
Fixes: 3565fce3a659 ("mm, x86: get_user_pages() for dax mappings")
Signed-off-by: Dan Williams <dan.j.williams(a)intel.com>
Suggested-by: Christoph Hellwig <hch(a)lst.de>
Cc: Doug Ledford <dledford(a)redhat.com>
Cc: Hal Rosenstock <hal.rosenstock(a)gmail.com>
Cc: Inki Dae <inki.dae(a)samsung.com>
Cc: Jan Kara <jack(a)suse.cz>
Cc: Jason Gunthorpe <jgg(a)mellanox.com>
Cc: Jeff Moyer <jmoyer(a)redhat.com>
Cc: Joonyoung Shim <jy0922.shim(a)samsung.com>
Cc: Kyungmin Park <kyungmin.park(a)samsung.com>
Cc: Mauro Carvalho Chehab <mchehab(a)kernel.org>
Cc: Mel Gorman <mgorman(a)suse.de>
Cc: Ross Zwisler <ross.zwisler(a)linux.intel.com>
Cc: Sean Hefty <sean.hefty(a)intel.com>
Cc: Seung-Woo Kim <sw0312.kim(a)samsung.com>
Cc: Vlastimil Babka <vbabka(a)suse.cz>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org>
diff --git a/include/linux/fs.h b/include/linux/fs.h
index bbd92da0946e..9dc498d16cc1 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -3194,6 +3194,20 @@ static inline bool vma_is_dax(struct vm_area_struct *vma)
return vma->vm_file && IS_DAX(vma->vm_file->f_mapping->host);
}
+static inline bool vma_is_fsdax(struct vm_area_struct *vma)
+{
+ struct inode *inode;
+
+ if (!vma->vm_file)
+ return false;
+ if (!vma_is_dax(vma))
+ return false;
+ inode = file_inode(vma->vm_file);
+ if (inode->i_mode == S_IFCHR)
+ return false; /* device-dax */
+ return true;
+}
+
static inline int iocb_flags(struct file *file)
{
int res = 0;
diff --git a/include/linux/mm.h b/include/linux/mm.h
index b3b6a7e313e9..ea818ff739cd 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1380,6 +1380,19 @@ long get_user_pages_locked(unsigned long start, unsigned long nr_pages,
unsigned int gup_flags, struct page **pages, int *locked);
long get_user_pages_unlocked(unsigned long start, unsigned long nr_pages,
struct page **pages, unsigned int gup_flags);
+#ifdef CONFIG_FS_DAX
+long get_user_pages_longterm(unsigned long start, unsigned long nr_pages,
+ unsigned int gup_flags, struct page **pages,
+ struct vm_area_struct **vmas);
+#else
+static inline long get_user_pages_longterm(unsigned long start,
+ unsigned long nr_pages, unsigned int gup_flags,
+ struct page **pages, struct vm_area_struct **vmas)
+{
+ return get_user_pages(start, nr_pages, gup_flags, pages, vmas);
+}
+#endif /* CONFIG_FS_DAX */
+
int get_user_pages_fast(unsigned long start, int nr_pages, int write,
struct page **pages);
diff --git a/mm/gup.c b/mm/gup.c
index 85cc822fd403..d3fb60e5bfac 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -1095,6 +1095,70 @@ long get_user_pages(unsigned long start, unsigned long nr_pages,
}
EXPORT_SYMBOL(get_user_pages);
+#ifdef CONFIG_FS_DAX
+/*
+ * This is the same as get_user_pages() in that it assumes we are
+ * operating on the current task's mm, but it goes further to validate
+ * that the vmas associated with the address range are suitable for
+ * longterm elevated page reference counts. For example, filesystem-dax
+ * mappings are subject to the lifetime enforced by the filesystem and
+ * we need guarantees that longterm users like RDMA and V4L2 only
+ * establish mappings that have a kernel enforced revocation mechanism.
+ *
+ * "longterm" == userspace controlled elevated page count lifetime.
+ * Contrast this to iov_iter_get_pages() usages which are transient.
+ */
+long get_user_pages_longterm(unsigned long start, unsigned long nr_pages,
+ unsigned int gup_flags, struct page **pages,
+ struct vm_area_struct **vmas_arg)
+{
+ struct vm_area_struct **vmas = vmas_arg;
+ struct vm_area_struct *vma_prev = NULL;
+ long rc, i;
+
+ if (!pages)
+ return -EINVAL;
+
+ if (!vmas) {
+ vmas = kcalloc(nr_pages, sizeof(struct vm_area_struct *),
+ GFP_KERNEL);
+ if (!vmas)
+ return -ENOMEM;
+ }
+
+ rc = get_user_pages(start, nr_pages, gup_flags, pages, vmas);
+
+ for (i = 0; i < rc; i++) {
+ struct vm_area_struct *vma = vmas[i];
+
+ if (vma == vma_prev)
+ continue;
+
+ vma_prev = vma;
+
+ if (vma_is_fsdax(vma))
+ break;
+ }
+
+ /*
+ * Either get_user_pages() failed, or the vma validation
+ * succeeded, in either case we don't need to put_page() before
+ * returning.
+ */
+ if (i >= rc)
+ goto out;
+
+ for (i = 0; i < rc; i++)
+ put_page(pages[i]);
+ rc = -EOPNOTSUPP;
+out:
+ if (vmas != vmas_arg)
+ kfree(vmas);
+ return rc;
+}
+EXPORT_SYMBOL(get_user_pages_longterm);
+#endif /* CONFIG_FS_DAX */
+
/**
* populate_vma_page_range() - populate a range of pages in the vma.
* @vma: target vma