kernel/linux.git/include, branch v4.11.2

dax: prevent invalidation of mapped DAX entries

2017-05-20T12:49:48+00:00

commit 4636e70bb0a8b871998b6841a2e4b205cf2bc863 upstream. Patch series "mm,dax: Fix data corruption due to mmap inconsistency", v4. This series fixes data corruption that can happen for DAX mounts when page faults race with write(2) and as a result page tables get out of sync with block mappings in the filesystem and thus data seen through mmap is different from data seen through read(2). The series passes testing with t_mmap_stale test program from Ross and also other mmap related tests on DAX filesystem. This patch (of 4): dax_invalidate_mapping_entry() currently removes DAX exceptional entries only if they are clean and unlocked. This is done via: invalidate_mapping_pages() invalidate_exceptional_entry() dax_invalidate_mapping_entry() However, for page cache pages removed in invalidate_mapping_pages() there is an additional criteria which is that the page must not be mapped. This is noted in the comments above invalidate_mapping_pages() and is checked in invalidate_inode_page(). For DAX entries this means that we can can end up in a situation where a DAX exceptional entry, either a huge zero page or a regular DAX entry, could end up mapped but without an associated radix tree entry. This is inconsistent with the rest of the DAX code and with what happens in the page cache case. We aren't able to unmap the DAX exceptional entry because according to its comments invalidate_mapping_pages() isn't allowed to block, and unmap_mapping_range() takes a write lock on the mapping->i_mmap_rwsem. Since we essentially never have unmapped DAX entries to evict from the radix tree, just remove dax_invalidate_mapping_entry(). Fixes: c6dcf52c23d2 ("mm: Invalidate DAX radix tree entries only if appropriate") Link: http://lkml.kernel.org/r/20170510085419.27601-2-jack@suse.cz Signed-off-by: Ross Zwisler Signed-off-by: Jan Kara Reported-by: Jan Kara Cc: Dan Williams Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

mm: vmscan: fix IO/refault regression in cache workingset transition

2017-05-20T12:49:46+00:00

commit 2a2e48854d704214dac7546e87ae0e4daa0e61a0 upstream. Since commit 59dc76b0d4df ("mm: vmscan: reduce size of inactive file list") we noticed bigger IO spikes during changes in cache access patterns. The patch in question shrunk the inactive list size to leave more room for the current workingset in the presence of streaming IO. However, workingset transitions that previously happened on the inactive list are now pushed out of memory and incur more refaults to complete. This patch disables active list protection when refaults are being observed. This accelerates workingset transitions, and allows more of the new set to establish itself from memory, without eating into the ability to protect the established workingset during stable periods. The workloads that were measurably affected for us were hit pretty bad by it, with refault/majfault rates doubling and tripling during cache transitions, and the machines sustaining half-hour periods of 100% IO utilization, where they'd previously have sub-minute peaks at 60-90%. Stateful services that handle user data tend to be more conservative with kernel upgrades. As a result we hit most page cache issues with some delay, as was the case here. The severity seemed to warrant a stable tag. Fixes: 59dc76b0d4df ("mm: vmscan: reduce size of inactive file list") Link: http://lkml.kernel.org/r/20170404220052.27593-1-hannes@cmpxchg.org Signed-off-by: Johannes Weiner Cc: Rik van Riel Cc: Mel Gorman Cc: Michal Hocko Cc: Vladimir Davydov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

Revert "KVM: Support vCPU-based gfn->hva cache"

2017-05-20T12:49:42+00:00

commit 4e335d9e7ddbcf83d03e7fbe65797ebed2272c18 upstream. This reverts commit bbd6411513aa8ef3ea02abab61318daf87c1af1e. I've been sitting on this revert for too long and it unfortunately missed 4.11. It's also the reason why I haven't merged ring-based dirty tracking for 4.12. Using kvm_vcpu_memslots in kvm_gfn_to_hva_cache_init and kvm_vcpu_write_guest_offset_cached means that the MSR value can now be used to access SMRAM, simply by making it point to an SMRAM physical address. This is problematic because it lets the guest OS overwrite memory that it shouldn't be able to touch. Fixes: bbd6411513aa8ef3ea02abab61318daf87c1af1e Signed-off-by: Paolo Bonzini Signed-off-by: Greg Kroah-Hartman

block: get rid of blk_integrity_revalidate()

2017-05-14T12:06:03+00:00

commit 19b7ccf8651df09d274671b53039c672a52ad84d upstream. Commit 25520d55cdb6 ("block: Inline blk_integrity in struct gendisk") introduced blk_integrity_revalidate(), which seems to assume ownership of the stable pages flag and unilaterally clears it if no blk_integrity profile is registered: if (bi->profile) disk->queue->backing_dev_info->capabilities |= BDI_CAP_STABLE_WRITES; else disk->queue->backing_dev_info->capabilities &= ~BDI_CAP_STABLE_WRITES; It's called from revalidate_disk() and rescan_partitions(), making it impossible to enable stable pages for drivers that support partitions and don't use blk_integrity: while the call in revalidate_disk() can be trivially worked around (see zram, which doesn't support partitions and hence gets away with zram_revalidate_disk()), rescan_partitions() can be triggered from userspace at any time. This breaks rbd, where the ceph messenger is responsible for generating/verifying CRCs. Since blk_integrity_{un,}register() "must" be used for (un)registering the integrity profile with the block layer, move BDI_CAP_STABLE_WRITES setting there. This way drivers that call blk_integrity_register() and use integrity infrastructure won't interfere with drivers that don't but still want stable pages. Fixes: 25520d55cdb6 ("block: Inline blk_integrity in struct gendisk") Cc: "Martin K. Petersen" Cc: Christoph Hellwig Cc: Mike Snitzer Tested-by: Dan Williams Signed-off-by: Ilya Dryomov Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman

xen/arm,arm64: fix xen_dma_ops after 815dd18 "Consolidate get_dma_ops..."

2017-05-14T12:06:02+00:00

commit e058632670b709145730a134acc3f83f392f7aa7 upstream. The following commit: commit 815dd18788fe0d41899f51b91d0560279cf16b0d Author: Bart Van Assche Date: Fri Jan 20 13:04:04 2017 -0800 treewide: Consolidate get_dma_ops() implementations rearranges get_dma_ops in a way that xen_dma_ops are not returned when running on Xen anymore, dev->dma_ops is returned instead (see arch/arm/include/asm/dma-mapping.h:get_arch_dma_ops and include/linux/dma-mapping.h:get_dma_ops). Fix the problem by storing dev->dma_ops in dev_archdata, and setting dev->dma_ops to xen_dma_ops. This way, xen_dma_ops is returned naturally by get_dma_ops. The Xen code can retrieve the original dev->dma_ops from dev_archdata when needed. It also allows us to remove __generic_dma_ops from common headers. Signed-off-by: Stefano Stabellini Tested-by: Julien Grall Suggested-by: Catalin Marinas Reviewed-by: Catalin Marinas CC: linux@armlinux.org.uk CC: catalin.marinas@arm.com CC: will.deacon@arm.com CC: boris.ostrovsky@oracle.com CC: jgross@suse.com CC: Julien Grall Signed-off-by: Greg Kroah-Hartman

f2fs: sanity check segment count

2017-05-14T12:06:02+00:00

commit b9dd46188edc2f0d1f37328637860bb65a771124 upstream. F2FS uses 4 bytes to represent block address. As a result, supported size of disk is 16 TB and it equals to 16 * 1024 * 1024 / 2 segments. Signed-off-by: Jin Qian Signed-off-by: Jaegeuk Kim Signed-off-by: Greg Kroah-Hartman

tcp: randomize timestamps on syncookies

2017-05-14T12:06:02+00:00

[ Upstream commit 84b114b98452c431299d99c135f751659e517acb ] Whole point of randomization was to hide server uptime, but an attacker can simply start a syn flood and TCP generates 'old style' timestamps, directly revealing server jiffies value. Also, TSval sent by the server to a particular remote address vary depending on syncookies being sent or not, potentially triggering PAWS drops for innocent clients. Lets implement proper randomization, including for SYNcookies. Also we do not need to export sysctl_tcp_timestamps, since it is not used from a module. In v2, I added Florian feedback and contribution, adding tsoff to tcp_get_cookie_sock(). v3 removed one unused variable in tcp_v4_connect() as Florian spotted. Fixes: 95a22caee396c ("tcp: randomize tcp timestamp offsets for each connection") Signed-off-by: Eric Dumazet Reviewed-by: Florian Westphal Tested-by: Florian Westphal Cc: Yuchung Cheng Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

ipv6: reorder ip6_route_dev_notifier after ipv6_dev_notf

2017-05-14T12:06:02+00:00

[ Upstream commit 242d3a49a2a1a71d8eb9f953db1bcaa9d698ce00 ] For each netns (except init_net), we initialize its null entry in 3 places: 1) The template itself, as we use kmemdup() 2) Code around dst_init_metrics() in ip6_route_net_init() 3) ip6_route_dev_notify(), which is supposed to initialize it after loopback registers Unfortunately the last one still happens in a wrong order because we expect to initialize net->ipv6.ip6_null_entry->rt6i_idev to net->loopback_dev's idev, thus we have to do that after we add idev to loopback. However, this notifier has priority == 0 same as ipv6_dev_notf, and ipv6_dev_notf is registered after ip6_route_dev_notifier so it is called actually after ip6_route_dev_notifier. This is similar to commit 2f460933f58e ("ipv6: initialize route null entry in addrconf_init()") which fixes init_net. Fix it by picking a smaller priority for ip6_route_dev_notifier. Also, we have to release the refcnt accordingly when unregistering loopback_dev because device exit functions are called before subsys exit functions. Acked-by: David Ahern Tested-by: David Ahern Signed-off-by: Cong Wang Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

ipv6: initialize route null entry in addrconf_init()

2017-05-14T12:06:02+00:00

[ Upstream commit 2f460933f58eee3393aba64f0f6d14acb08d1724 ] Andrey reported a crash on init_net.ipv6.ip6_null_entry->rt6i_idev since it is always NULL. This is clearly wrong, we have code to initialize it to loopback_dev, unfortunately the order is still not correct. loopback_dev is registered very early during boot, we lose a chance to re-initialize it in notifier. addrconf_init() is called after ip6_route_init(), which means we have no chance to correct it. Fix it by moving this initialization explicitly after ipv6_add_dev(init_net.loopback_dev) in addrconf_init(). Reported-by: Andrey Konovalov Signed-off-by: Cong Wang Tested-by: Andrey Konovalov Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2017-04-27T18:09:37+00:00

Pull vfs fixes from Al Viro: - fix orangefs handling of faults on write() - I'd missed that one back when orangefs was going through review. - readdir counterpart of "9p: cope with bogus responses from server in p9_client_{read,write}" - server might be lying or broken, and we'd better not overrun the kmalloc'ed buffer we are copying the results into. - NFS O_DIRECT read/write can leave iov_iter advanced by too much; that's what had been causing iov_iter_pipe() warnings davej had been seeing. - statx_timestamp.tv_nsec type fix (s32 -> u32). That one really should go in before 4.11. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: uapi: change the type of struct statx_timestamp.tv_nsec to unsigned fix nfs O_DIRECT advancing iov_iter too much p9_client_readdir() fix orangefs_bufmap_copy_from_iovec(): fix EFAULT handling