Revision 9a291a7c9428155e8e623e4a3989f8be47134df5 authored by James Morse on 02 June 2017, 21:46:46 UTC, committed by Linus Torvalds on 02 June 2017, 22:07:38 UTC
KVM uses get_user_pages() to resolve its stage2 faults. KVM sets the FOLL_HWPOISON flag causing faultin_page() to return -EHWPOISON when it finds a VM_FAULT_HWPOISON. KVM handles these hwpoison pages as a special case. (check_user_page_hwpoison()) When huge pages are involved, this doesn't work so well. get_user_pages() calls follow_hugetlb_page(), which stops early if it receives VM_FAULT_HWPOISON from hugetlb_fault(), eventually returning -EFAULT to the caller. The step to map this to -EHWPOISON based on the FOLL_ flags is missing. The hwpoison special case is skipped, and -EFAULT is returned to user-space, causing Qemu or kvmtool to exit. Instead, move this VM_FAULT_ to errno mapping code into a header file and use it from faultin_page() and follow_hugetlb_page(). With this, KVM works as expected. This isn't a problem for arm64 today as we haven't enabled MEMORY_FAILURE, but I can't see any reason this doesn't happen on x86 too, so I think this should be a fix. This doesn't apply earlier than stable's v4.11.1 due to all sorts of cleanup. [james.morse@arm.com: add vm_fault_to_errno() call to faultin_page()] suggested. Link: http://lkml.kernel.org/r/20170525171035.16359-1-james.morse@arm.com [akpm@linux-foundation.org: coding-style fixes] Link: http://lkml.kernel.org/r/20170524160900.28786-1-james.morse@arm.com Signed-off-by: James Morse <james.morse@arm.com> Acked-by: Punit Agrawal <punit.agrawal@arm.com> Acked-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com> Cc: <stable@vger.kernel.org> [4.11.1+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Kconfig | -rw-r--r-- | 5.8 KB |
Makefile | -rw-r--r-- | 1.2 KB |
cache_lib.c | -rw-r--r-- | 3.8 KB |
cache_lib.h | -rw-r--r-- | 1016 bytes |
callback.c | -rw-r--r-- | 10.9 KB |
callback.h | -rw-r--r-- | 5.1 KB |
callback_proc.c | -rw-r--r-- | 16.7 KB |
callback_xdr.c | -rw-r--r-- | 25.7 KB |
client.c | -rw-r--r-- | 33.3 KB |
delegation.c | -rw-r--r-- | 29.0 KB |
delegation.h | -rw-r--r-- | 2.9 KB |
dir.c | -rw-r--r-- | 63.5 KB |
direct.c | -rw-r--r-- | 28.6 KB |
dns_resolve.c | -rw-r--r-- | 10.0 KB |
dns_resolve.h | -rw-r--r-- | 812 bytes |
file.c | -rw-r--r-- | 22.0 KB |
fscache-index.c | -rw-r--r-- | 9.3 KB |
fscache.c | -rw-r--r-- | 11.9 KB |
fscache.h | -rw-r--r-- | 6.5 KB |
getroot.c | -rw-r--r-- | 3.5 KB |
inode.c | -rw-r--r-- | 58.5 KB |
internal.h | -rw-r--r-- | 24.0 KB |
io.c | -rw-r--r-- | 4.0 KB |
iostat.h | -rw-r--r-- | 1.8 KB |
mount_clnt.c | -rw-r--r-- | 12.2 KB |
namespace.c | -rw-r--r-- | 6.9 KB |
netns.h | -rw-r--r-- | 903 bytes |
nfs.h | -rw-r--r-- | 993 bytes |
nfs2super.c | -rw-r--r-- | 569 bytes |
nfs2xdr.c | -rw-r--r-- | 25.9 KB |
nfs3_fs.h | -rw-r--r-- | 1.1 KB |
nfs3acl.c | -rw-r--r-- | 8.0 KB |
nfs3client.c | -rw-r--r-- | 3.1 KB |
nfs3proc.c | -rw-r--r-- | 25.2 KB |
nfs3super.c | -rw-r--r-- | 649 bytes |
nfs3xdr.c | -rw-r--r-- | 54.9 KB |
nfs42.h | -rw-r--r-- | 804 bytes |
nfs42proc.c | -rw-r--r-- | 14.4 KB |
nfs42xdr.c | -rw-r--r-- | 15.7 KB |
nfs4_fs.h | -rw-r--r-- | 18.6 KB |
nfs4client.c | -rw-r--r-- | 31.1 KB |
nfs4file.c | -rw-r--r-- | 6.2 KB |
nfs4getroot.c | -rw-r--r-- | 975 bytes |
nfs4idmap.c | -rw-r--r-- | 19.2 KB |
nfs4idmap.h | -rw-r--r-- | 2.7 KB |
nfs4namespace.c | -rw-r--r-- | 12.7 KB |
nfs4proc.c | -rw-r--r-- | 251.5 KB |
nfs4renewd.c | -rw-r--r-- | 4.8 KB |
nfs4session.c | -rw-r--r-- | 16.6 KB |
nfs4session.h | -rw-r--r-- | 5.1 KB |
nfs4state.c | -rw-r--r-- | 65.9 KB |
nfs4super.c | -rw-r--r-- | 8.7 KB |
nfs4sysctl.c | -rw-r--r-- | 1.4 KB |
nfs4trace.c | -rw-r--r-- | 435 bytes |
nfs4trace.h | -rw-r--r-- | 42.9 KB |
nfs4xdr.c | -rw-r--r-- | 197.0 KB |
nfsroot.c | -rw-r--r-- | 9.5 KB |
nfstrace.c | -rw-r--r-- | 292 bytes |
nfstrace.h | -rw-r--r-- | 18.0 KB |
pagelist.c | -rw-r--r-- | 33.9 KB |
pnfs.c | -rw-r--r-- | 73.0 KB |
pnfs.h | -rw-r--r-- | 23.0 KB |
pnfs_dev.c | -rw-r--r-- | 9.6 KB |
pnfs_nfs.c | -rw-r--r-- | 24.1 KB |
proc.c | -rw-r--r-- | 18.8 KB |
read.c | -rw-r--r-- | 11.5 KB |
super.c | -rw-r--r-- | 74.9 KB |
symlink.c | -rw-r--r-- | 1.8 KB |
sysctl.c | -rw-r--r-- | 1.3 KB |
unlink.c | -rw-r--r-- | 13.5 KB |
write.c | -rw-r--r-- | 54.9 KB |
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