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authorDavid S. Miller <davem@davemloft.net>2015-04-02 16:16:53 -0400
committerDavid S. Miller <davem@davemloft.net>2015-04-02 16:16:53 -0400
commit9f0d34bc344889c2e6c593bd949d7ab821f0f4a5 (patch)
treee5bfc776a09315afa4dbcae97ac04f2cca239c96 /mm/memory.c
parente4a924f5768c55002c02ceba9b9f86824c35f956 (diff)
parent0a4812798fae4f6bfcaab51e31b3898ff5ea3108 (diff)
downloadop-kernel-dev-9f0d34bc344889c2e6c593bd949d7ab821f0f4a5.zip
op-kernel-dev-9f0d34bc344889c2e6c593bd949d7ab821f0f4a5.tar.gz
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts: drivers/net/usb/asix_common.c drivers/net/usb/sr9800.c drivers/net/usb/usbnet.c include/linux/usb/usbnet.h net/ipv4/tcp_ipv4.c net/ipv6/tcp_ipv6.c The TCP conflicts were overlapping changes. In 'net' we added a READ_ONCE() to the socket cached RX route read, whilst in 'net-next' Eric Dumazet touched the surrounding code dealing with how mini sockets are handled. With USB, it's a case of the same bug fix first going into net-next and then I cherry picked it back into net. Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'mm/memory.c')
-rw-r--r--mm/memory.c22
1 files changed, 12 insertions, 10 deletions
diff --git a/mm/memory.c b/mm/memory.c
index 411144f..97839f5 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -3035,6 +3035,7 @@ static int do_numa_page(struct mm_struct *mm, struct vm_area_struct *vma,
int last_cpupid;
int target_nid;
bool migrated = false;
+ bool was_writable = pte_write(pte);
int flags = 0;
/* A PROT_NONE fault should not end up here */
@@ -3059,6 +3060,8 @@ static int do_numa_page(struct mm_struct *mm, struct vm_area_struct *vma,
/* Make it present again */
pte = pte_modify(pte, vma->vm_page_prot);
pte = pte_mkyoung(pte);
+ if (was_writable)
+ pte = pte_mkwrite(pte);
set_pte_at(mm, addr, ptep, pte);
update_mmu_cache(vma, addr, ptep);
@@ -3069,16 +3072,14 @@ static int do_numa_page(struct mm_struct *mm, struct vm_area_struct *vma,
}
/*
- * Avoid grouping on DSO/COW pages in specific and RO pages
- * in general, RO pages shouldn't hurt as much anyway since
- * they can be in shared cache state.
- *
- * FIXME! This checks "pmd_dirty()" as an approximation of
- * "is this a read-only page", since checking "pmd_write()"
- * is even more broken. We haven't actually turned this into
- * a writable page, so pmd_write() will always be false.
+ * Avoid grouping on RO pages in general. RO pages shouldn't hurt as
+ * much anyway since they can be in shared cache state. This misses
+ * the case where a mapping is writable but the process never writes
+ * to it but pte_write gets cleared during protection updates and
+ * pte_dirty has unpredictable behaviour between PTE scan updates,
+ * background writeback, dirty balancing and application behaviour.
*/
- if (!pte_dirty(pte))
+ if (!(vma->vm_flags & VM_WRITE))
flags |= TNF_NO_GROUP;
/*
@@ -3102,7 +3103,8 @@ static int do_numa_page(struct mm_struct *mm, struct vm_area_struct *vma,
if (migrated) {
page_nid = target_nid;
flags |= TNF_MIGRATED;
- }
+ } else
+ flags |= TNF_MIGRATE_FAIL;
out:
if (page_nid != -1)
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