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2015-09-20Merge branch 'libnvdimm-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm Pull libnvdimm fixes from Dan Williams: - a boot regression (since v4.2) fix for some ARM configurations from Tyler - regression (since v4.1) fixes for mkfs.xfs on a DAX enabled device from Jeff. These are tagged for -stable. - a pair of locking fixes from Axel that are hidden from lockdep since they involve device_lock(). The "btt" one is tagged for -stable, the other only applies to the new "pfn" mechanism in v4.3. - a fix for the pmem ->rw_page() path to use wmb_pmem() from Ross. * 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: mm: fix type cast in __pfn_to_phys() pmem: add proper fencing to pmem_rw_page() libnvdimm: pfn_devs: Fix locking in namespace_store libnvdimm: btt_devs: Fix locking in namespace_store blockdev: don't set S_DAX for misaligned partitions dax: fix O_DIRECT I/O to the last block of a blockdev
2015-09-20fs-writeback: unplug before cond_resched in writeback_sb_inodesChris Mason
Commit 505a666ee3fc ("writeback: plug writeback in wb_writeback() and writeback_inodes_wb()") has us holding a plug during writeback_sb_inodes, which increases the merge rate when relatively contiguous small files are written by the filesystem. It helps both on flash and spindles. For an fs_mark workload creating 4K files in parallel across 8 drives, this commit improves performance ~9% more by unplugging before calling cond_resched(). cond_resched() doesn't trigger an implicit unplug, so explicitly getting the IO down to the device before scheduling reduces latencies for anyone waiting on clean pages. It also cuts down on how often we use kblockd to unplug, which means less work bouncing from one workqueue to another. Many more details about how we got here: https://lkml.org/lkml/2015/9/11/570 Signed-off-by: Chris Mason <clm@fb.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-18userfaultfd: add missing mmput() in error pathEric Biggers
This fixes a memleak if anon_inode_getfile() fails in userfaultfd(). Signed-off-by: Eric Biggers <ebiggers3@gmail.com> Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-16blockdev: don't set S_DAX for misaligned partitionsJeff Moyer
The dax code doesn't currently support misaligned partitions, so disable O_DIRECT via dax until such time as that support materializes. Cc: <stable@vger.kernel.org> Suggested-by: Boaz Harrosh <boaz@plexistor.com> Signed-off-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-09-16dax: fix O_DIRECT I/O to the last block of a blockdevJeff Moyer
commit bbab37ddc20b (block: Add support for DAX reads/writes to block devices) caused a regression in mkfs.xfs. That utility sets the block size of the device to the logical block size using the BLKBSZSET ioctl, and then issues a single sector read from the last sector of the device. This results in the dax_io code trying to do a page-sized read from 512 bytes from the end of the device. The result is -ERANGE being returned to userspace. The fix is to align the block to the page size before calling get_block. Thanks to willy for simplifying my original patch. Cc: <stable@vger.kernel.org> Signed-off-by: Jeff Moyer <jmoyer@redhat.com> Tested-by: Linda Knippers <linda.knippers@hp.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-09-14Merge branch 'for-next' of git://git.samba.org/sfrench/cifs-2.6Linus Torvalds
Pull CIFS fixes from Steve French: "Two small cifs fixes" * 'for-next' of git://git.samba.org/sfrench/cifs-2.6: [CIFS] mount option sec=none not displayed properly in /proc/mounts CIFS: fix type confusion in copy offload ioctl
2015-09-12Merge branch 'writeback-plugging'Linus Torvalds
Fix up the writeback plugging introduced in commit d353d7587d02 ("writeback: plug writeback at a high level") that then caused problems due to the unplug happening with a spinlock held. * writeback-plugging: writeback: plug writeback in wb_writeback() and writeback_inodes_wb() Revert "writeback: plug writeback at a high level"
2015-09-12writeback: plug writeback in wb_writeback() and writeback_inodes_wb()Linus Torvalds
We had to revert the pluggin in writeback_sb_inodes() because the wb->list_lock is held, but we could easily plug at a higher level before taking that lock, and unplug after releasing it. This does that. Chris will run performance numbers, just to verify that this approach is comparable to the alternative (we could just drop and re-take the lock around the blk_finish_plug() rather than these two commits. I'd have preferred waiting for actual performance numbers before picking one approach over the other, but I don't want to release rc1 with the known "sleeping function called from invalid context" issue, so I'll pick this cleanup version for now. But if the numbers show that we really want to plug just at the writeback_sb_inodes() level, and we should just play ugly games with the spinlock, we'll switch to that. Cc: Chris Mason <clm@fb.com> Cc: Josef Bacik <jbacik@fb.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Neil Brown <neilb@suse.de> Cc: Jan Kara <jack@suse.cz> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-12Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge fourth patch-bomb from Andrew Morton: - sys_membarier syscall - seq_file interface changes - a few misc fixups * emailed patches from Andrew Morton <akpm@linux-foundation.org>: revert "ocfs2/dlm: use list_for_each_entry instead of list_for_each" mm/early_ioremap: add explicit #include of asm/early_ioremap.h fs/seq_file: convert int seq_vprint/seq_printf/etc... returns to void selftests: enhance membarrier syscall test selftests: add membarrier syscall test sys_membarrier(): system-wide memory barrier (generic, x86) MODSIGN: fix a compilation warning in extract-cert
2015-09-12[CIFS] mount option sec=none not displayed properly in /proc/mountsSteve French
When the user specifies "sec=none" in a cifs mount, we set sec_type as unspecified (and set a flag and the username will be null) rather than setting sectype as "none" so cifs_show_security was not properly displaying it in cifs /proc/mounts entries. Signed-off-by: Steve French <steve.french@primarydata.com> Reviewed-by: Jeff Layton <jlayton@poochiereds.net>
2015-09-11revert "ocfs2/dlm: use list_for_each_entry instead of list_for_each"Andrew Morton
Revert commit f83c7b5e9fd6 ("ocfs2/dlm: use list_for_each_entry instead of list_for_each"). list_for_each_entry() will dereference its `pos' argument, which can be NULL in dlm_process_recovery_data(). Reported-by: Julia Lawall <julia.lawall@lip6.fr> Reported-by: Fengguang Wu <fengguang.wu@gmail.com> Cc: Joseph Qi <joseph.qi@huawei.com> Cc: Mark Fasheh <mfasheh@suse.de> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-11fs/seq_file: convert int seq_vprint/seq_printf/etc... returns to voidJoe Perches
The seq_<foo> function return values were frequently misused. See: commit 1f33c41c03da ("seq_file: Rename seq_overflow() to seq_has_overflowed() and make public") All uses of these return values have been removed, so convert the return types to void. Miscellanea: o Move seq_put_decimal_<type> and seq_escape prototypes closer the other seq_vprintf prototypes o Reorder seq_putc and seq_puts to return early on overflow o Add argument names to seq_vprintf and seq_printf o Update the seq_escape kernel-doc o Convert a couple of leading spaces to tabs in seq_escape Signed-off-by: Joe Perches <joe@perches.com> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Mark Brown <broonie@kernel.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Joerg Roedel <jroedel@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-11Revert "writeback: plug writeback at a high level"Linus Torvalds
This reverts commit d353d7587d02116b9732d5c06615aed75a4d3a47. Doing the block layer plug/unplug inside writeback_sb_inodes() is broken, because that function is actually called with a spinlock held: wb->list_lock, as pointed out by Chris Mason. Chris suggested just dropping and re-taking the spinlock around the blk_finish_plug() call (the plgging itself can happen under the spinlock), and that would technically work, but is just disgusting. We do something fairly similar - but not quite as disgusting because we at least have a better reason for it - in writeback_single_inode(), so it's not like the caller can depend on the lock being held over the call, but in this case there just isn't any good reason for that "release and re-take the lock" pattern. [ In general, we should really strive to avoid the "release and retake" pattern for locks, because in the general case it can easily cause subtle bugs when the caller caches any state around the call that might be invalidated by dropping the lock even just temporarily. ] But in this case, the plugging should be easy to just move up to the callers before the spinlock is taken, which should even improve the effectiveness of the plug. So there is really no good reason to play games with locking here. I'll send off a test-patch so that Dave Chinner can verify that that plug movement works. In the meantime this just reverts the problematic commit and adds a comment to the function so that we hopefully don't make this mistake again. Reported-by: Chris Mason <clm@fb.com> Cc: Josef Bacik <jbacik@fb.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Neil Brown <neilb@suse.de> Cc: Jan Kara <jack@suse.cz> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-11Merge branch 'for-linus-4.3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs Pull btrfs cleanups and fixes from Chris Mason: "These are small cleanups, and also some fixes for our async worker thread initialization. I was having some trouble testing these, but it ended up being a combination of changing around my test servers and a shiny new schedule while atomic from the new start/finish_plug in writeback_sb_inodes(). That one only hits on btrfs raid5/6 or MD raid10, and if I wasn't changing a bunch of things in my test setup at once it would have been really clear. Fix for writeback_sb_inodes() on the way as well" * 'for-linus-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: Btrfs: cleanup: remove unnecessary check before btrfs_free_path is called btrfs: async_thread: Fix workqueue 'max_active' value when initializing btrfs: Add raid56 support for updating num_tolerated_disk_barrier_failures in btrfs_balance btrfs: Cleanup for btrfs_calc_num_tolerated_disk_barrier_failures btrfs: Remove noused chunk_tree and chunk_objectid from scrub_enumerate_chunks and scrub_chunk btrfs: Update out-of-date "skip parity stripe" comment
2015-09-11Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client Pull Ceph update from Sage Weil: "There are a few fixes for snapshot behavior with CephFS and support for the new keepalive protocol from Zheng, a libceph fix that affects both RBD and CephFS, a few bug fixes and cleanups for RBD from Ilya, and several small fixes and cleanups from Jianpeng and others" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: ceph: improve readahead for file holes ceph: get inode size for each append write libceph: check data_len in ->alloc_msg() libceph: use keepalive2 to verify the mon session is alive rbd: plug rbd_dev->header.object_prefix memory leak rbd: fix double free on rbd_dev->header_name libceph: set 'exists' flag for newly up osd ceph: cleanup use of ceph_msg_get ceph: no need to get parent inode in ceph_open ceph: remove the useless judgement ceph: remove redundant test of head->safe and silence static analysis warnings ceph: fix queuing inode to mdsdir's snaprealm libceph: rename con_work() to ceph_con_workfn() libceph: Avoid holding the zero page on ceph_msgr_slab_init errors libceph: remove the unused macro AES_KEY_SIZE ceph: invalidate dirty pages after forced umount ceph: EIO all operations after forced umount
2015-09-11Merge tag 'gfs2-merge-window' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2 Pull GFS2 updates from Bob Peterson: "Here is a list of patches we've accumulated for GFS2 for the current upstream merge window. This time we've only got six patches, many of which are very small: - three cleanups from Andreas Gruenbacher, including a nice cleanup of the sequence file code for the sbstats debugfs file. - a patch from Ben Hutchings that changes statistics variables from signed to unsigned. - two patches from me that increase GFS2's glock scalability by switching from a conventional hash table to rhashtable" * tag 'gfs2-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2: gfs2: A minor "sbstats" cleanup gfs2: Fix a typo in a comment gfs2: Make statistics unsigned, suitable for use with do_div() GFS2: Use resizable hash table for glocks GFS2: Move glock superblock pointer to field gl_name gfs2: Simplify the seq file code for "sbstats"
2015-09-11CIFS: fix type confusion in copy offload ioctlJann Horn
This might lead to local privilege escalation (code execution as kernel) for systems where the following conditions are met: - CONFIG_CIFS_SMB2 and CONFIG_CIFS_POSIX are enabled - a cifs filesystem is mounted where: - the mount option "vers" was used and set to a value >=2.0 - the attacker has write access to at least one file on the filesystem To attack this, an attacker would have to guess the target_tcon pointer (but guessing wrong doesn't cause a crash, it just returns an error code) and win a narrow race. CC: Stable <stable@vger.kernel.org> Signed-off-by: Jann Horn <jann@thejh.net> Signed-off-by: Steve French <smfrench@gmail.com>
2015-09-11Merge branch 'for-4.3/blkcg' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull blk-cg updates from Jens Axboe: "A bit later in the cycle, but this has been in the block tree for a a while. This is basically four patchsets from Tejun, that improve our buffered cgroup writeback. It was dependent on the other cgroup changes, but they went in earlier in this cycle. Series 1 is set of 5 patches that has cgroup writeback updates: - bdi_writeback iteration fix which could lead to some wb's being skipped or repeated during e.g. sync under memory pressure. - Simplification of wb work wait mechanism. - Writeback tracepoints updated to report cgroup. Series 2 is is a set of updates for the CFQ cgroup writeback handling: cfq has always charged all async IOs to the root cgroup. It didn't have much choice as writeback didn't know about cgroups and there was no way to tell who to blame for a given writeback IO. writeback finally grew support for cgroups and now tags each writeback IO with the appropriate cgroup to charge it against. This patchset updates cfq so that it follows the blkcg each bio is tagged with. Async cfq_queues are now shared across cfq_group, which is per-cgroup, instead of per-request_queue cfq_data. This makes all IOs follow the weight based IO resource distribution implemented by cfq. - Switched from GFP_ATOMIC to GFP_NOWAIT as suggested by Jeff. - Other misc review points addressed, acks added and rebased. Series 3 is the blkcg policy cleanup patches: This patchset contains assorted cleanups for blkcg_policy methods and blk[c]g_policy_data handling. - alloc/free added for blkg_policy_data. exit dropped. - alloc/free added for blkcg_policy_data. - blk-throttle's async percpu allocation is replaced with direct allocation. - all methods now take blk[c]g_policy_data instead of blkcg_gq or blkcg. And finally, series 4 is a set of patches cleaning up the blkcg stats handling: blkcg's stats have always been somwhat of a mess. This patchset tries to improve the situation a bit. - The following patches added to consolidate blkcg entry point and blkg creation. This is in itself is an improvement and helps colllecting common stats on bio issue. - per-blkg stats now accounted on bio issue rather than request completion so that bio based and request based drivers can behave the same way. The issue was spotted by Vivek. - cfq-iosched implements custom recursive stats and blk-throttle implements custom per-cpu stats. This patchset make blkcg core support both by default. - cfq-iosched and blk-throttle keep track of the same stats multiple times. Unify them" * 'for-4.3/blkcg' of git://git.kernel.dk/linux-block: (45 commits) blkcg: use CGROUP_WEIGHT_* scale for io.weight on the unified hierarchy blkcg: s/CFQ_WEIGHT_*/CFQ_WEIGHT_LEGACY_*/ blkcg: implement interface for the unified hierarchy blkcg: misc preparations for unified hierarchy interface blkcg: separate out tg_conf_updated() from tg_set_conf() blkcg: move body parsing from blkg_conf_prep() to its callers blkcg: mark existing cftypes as legacy blkcg: rename subsystem name from blkio to io blkcg: refine error codes returned during blkcg configuration blkcg: remove unnecessary NULL checks from __cfqg_set_weight_device() blkcg: reduce stack usage of blkg_rwstat_recursive_sum() blkcg: remove cfqg_stats->sectors blkcg: move io_service_bytes and io_serviced stats into blkcg_gq blkcg: make blkg_[rw]stat_recursive_sum() to be able to index into blkcg_gq blkcg: make blkcg_[rw]stat per-cpu blkcg: add blkg_[rw]stat->aux_cnt and replace cfq_group->dead_stats with it blkcg: consolidate blkg creation in blkcg_bio_issue_check() blk-throttle: improve queue bypass handling blkcg: move root blkg lookup optimization from throtl_lookup_tg() to __blkg_lookup() blkcg: inline [__]blkg_lookup() ...
2015-09-11Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge third patch-bomb from Andrew Morton: - even more of the rest of MM - lib/ updates - checkpatch updates - small changes to a few scruffy filesystems - kmod fixes/cleanups - kexec updates - a dma-mapping cleanup series from hch * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (81 commits) dma-mapping: consolidate dma_set_mask dma-mapping: consolidate dma_supported dma-mapping: cosolidate dma_mapping_error dma-mapping: consolidate dma_{alloc,free}_noncoherent dma-mapping: consolidate dma_{alloc,free}_{attrs,coherent} mm: use vma_is_anonymous() in create_huge_pmd() and wp_huge_pmd() mm: make sure all file VMAs have ->vm_ops set mm, mpx: add "vm_flags_t vm_flags" arg to do_mmap_pgoff() mm: mark most vm_operations_struct const namei: fix warning while make xmldocs caused by namei.c ipc: convert invalid scenarios to use WARN_ON zlib_deflate/deftree: remove bi_reverse() lib/decompress_unlzma: Do a NULL check for pointer lib/decompressors: use real out buf size for gunzip with kernel fs/affs: make root lookup from blkdev logical size sysctl: fix int -> unsigned long assignments in INT_MIN case kexec: export KERNEL_IMAGE_SIZE to vmcoreinfo kexec: align crash_notes allocation to make it be inside one physical page kexec: remove unnecessary test in kimage_alloc_crash_control_pages() kexec: split kexec_load syscall from kexec core code ...
2015-09-10mm: mark most vm_operations_struct constKirill A. Shutemov
With two exceptions (drm/qxl and drm/radeon) all vm_operations_struct structs should be constant. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Minchan Kim <minchan@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-10namei: fix warning while make xmldocs caused by namei.cMasanari Iida
Fix the following warnings: Warning(.//fs/namei.c:2422): No description found for parameter 'nd' Warning(.//fs/namei.c:2422): Excess function parameter 'nameidata' description in 'path_mountpoint' Signed-off-by: Masanari Iida <standby24x7@gmail.com> Acked-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-10fs/affs: make root lookup from blkdev logical sizePranay Kr. Srivastava
This patch resolves https://bugzilla.kernel.org/show_bug.cgi?id=16531. When logical blkdev size > 512 then sector numbers become larger than the device can support. Make affs start lookup based on the device's logical sector size instead of 512. Reported-by: Mark <markk@clara.co.uk> Suggested-by: Mark <markk@clara.co.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-10seq_file: provide an analogue of print_hex_dump()Andy Shevchenko
This introduces a new helper and switches current users to use it. All patches are compiled tested. kmemleak is tested via its own test suite. This patch (of 6): The new seq_hex_dump() is a complete analogue of print_hex_dump(). We have few users of this functionality already. It allows to reduce their codebase. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Joe Perches <joe@perches.com> Cc: Tadeusz Struk <tadeusz.struk@intel.com> Cc: Helge Deller <deller@gmx.de> Cc: Ingo Tuchscherer <ingo.tuchscherer@de.ibm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Vladimir Kondratiev <qca_vkondrat@qca.qualcomm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-10fs: Don't dump core if the corefile would become world-readable.Jann Horn
On a filesystem like vfat, all files are created with the same owner and mode independent of who created the file. When a vfat filesystem is mounted with root as owner of all files and read access for everyone, root's processes left world-readable coredumps on it (but other users' processes only left empty corefiles when given write access because of the uid mismatch). Given that the old behavior was inconsistent and insecure, I don't see a problem with changing it. Now, all processes refuse to dump core unless the resulting corefile will only be readable by their owner. Signed-off-by: Jann Horn <jann@thejh.net> Acked-by: Kees Cook <keescook@chromium.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-10fs: if a coredump already exists, unlink and recreate with O_EXCLJann Horn
It was possible for an attacking user to trick root (or another user) into writing his coredumps into an attacker-readable, pre-existing file using rename() or link(), causing the disclosure of secret data from the victim process' virtual memory. Depending on the configuration, it was also possible to trick root into overwriting system files with coredumps. Fix that issue by never writing coredumps into existing files. Requirements for the attack: - The attack only applies if the victim's process has a nonzero RLIMIT_CORE and is dumpable. - The attacker can trick the victim into coredumping into an attacker-writable directory D, either because the core_pattern is relative and the victim's cwd is attacker-writable or because an absolute core_pattern pointing to a world-writable directory is used. - The attacker has one of these: A: on a system with protected_hardlinks=0: execute access to a folder containing a victim-owned, attacker-readable file on the same partition as D, and the victim-owned file will be deleted before the main part of the attack takes place. (In practice, there are lots of files that fulfill this condition, e.g. entries in Debian's /var/lib/dpkg/info/.) This does not apply to most Linux systems because most distros set protected_hardlinks=1. B: on a system with protected_hardlinks=1: execute access to a folder containing a victim-owned, attacker-readable and attacker-writable file on the same partition as D, and the victim-owned file will be deleted before the main part of the attack takes place. (This seems to be uncommon.) C: on any system, independent of protected_hardlinks: write access to a non-sticky folder containing a victim-owned, attacker-readable file on the same partition as D (This seems to be uncommon.) The basic idea is that the attacker moves the victim-owned file to where he expects the victim process to dump its core. The victim process dumps its core into the existing file, and the attacker reads the coredump from it. If the attacker can't move the file because he does not have write access to the containing directory, he can instead link the file to a directory he controls, then wait for the original link to the file to be deleted (because the kernel checks that the link count of the corefile is 1). A less reliable variant that requires D to be non-sticky works with link() and does not require deletion of the original link: link() the file into D, but then unlink() it directly before the kernel performs the link count check. On systems with protected_hardlinks=0, this variant allows an attacker to not only gain information from coredumps, but also clobber existing, victim-writable files with coredumps. (This could theoretically lead to a privilege escalation.) Signed-off-by: Jann Horn <jann@thejh.net> Cc: Kees Cook <keescook@chromium.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-10hfs: fix B-tree corruption after insertion at position 0Hin-Tak Leung
Fix B-tree corruption when a new record is inserted at position 0 in the node in hfs_brec_insert(). This is an identical change to the corresponding hfs b-tree code to Sergei Antonov's "hfsplus: fix B-tree corruption after insertion at position 0", to keep similar code paths in the hfs and hfsplus drivers in sync, where appropriate. Signed-off-by: Hin-Tak Leung <htl10@users.sourceforge.net> Cc: Sergei Antonov <saproj@gmail.com> Cc: Joe Perches <joe@perches.com> Reviewed-by: Vyacheslav Dubeyko <slava@dubeyko.com> Cc: Anton Altaparmakov <anton@tuxera.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@infradead.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-10hfs,hfsplus: cache pages correctly between bnode_create and bnode_freeHin-Tak Leung
Pages looked up by __hfs_bnode_create() (called by hfs_bnode_create() and hfs_bnode_find() for finding or creating pages corresponding to an inode) are immediately kmap()'ed and used (both read and write) and kunmap()'ed, and should not be page_cache_release()'ed until hfs_bnode_free(). This patch fixes a problem I first saw in July 2012: merely running "du" on a large hfsplus-mounted directory a few times on a reasonably loaded system would get the hfsplus driver all confused and complaining about B-tree inconsistencies, and generates a "BUG: Bad page state". Most recently, I can generate this problem on up-to-date Fedora 22 with shipped kernel 4.0.5, by running "du /" (="/" + "/home" + "/mnt" + other smaller mounts) and "du /mnt" simultaneously on two windows, where /mnt is a lightly-used QEMU VM image of the full Mac OS X 10.9: $ df -i / /home /mnt Filesystem Inodes IUsed IFree IUse% Mounted on /dev/mapper/fedora-root 3276800 551665 2725135 17% / /dev/mapper/fedora-home 52879360 716221 52163139 2% /home /dev/nbd0p2 4294967295 1387818 4293579477 1% /mnt After applying the patch, I was able to run "du /" (60+ times) and "du /mnt" (150+ times) continuously and simultaneously for 6+ hours. There are many reports of the hfsplus driver getting confused under load and generating "BUG: Bad page state" or other similar issues over the years. [1] The unpatched code [2] has always been wrong since it entered the kernel tree. The only reason why it gets away with it is that the kmap/memcpy/kunmap follow very quickly after the page_cache_release() so the kernel has not had a chance to reuse the memory for something else, most of the time. The current RW driver appears to have followed the design and development of the earlier read-only hfsplus driver [3], where-by version 0.1 (Dec 2001) had a B-tree node-centric approach to read_cache_page()/page_cache_release() per bnode_get()/bnode_put(), migrating towards version 0.2 (June 2002) of caching and releasing pages per inode extents. When the current RW code first entered the kernel [2] in 2005, there was an REF_PAGES conditional (and "//" commented out code) to switch between B-node centric paging to inode-centric paging. There was a mistake with the direction of one of the REF_PAGES conditionals in __hfs_bnode_create(). In a subsequent "remove debug code" commit [4], the read_cache_page()/page_cache_release() per bnode_get()/bnode_put() were removed, but a page_cache_release() was mistakenly left in (propagating the "REF_PAGES <-> !REF_PAGE" mistake), and the commented-out page_cache_release() in bnode_release() (which should be spanned by !REF_PAGES) was never enabled. References: [1]: Michael Fox, Apr 2013 http://www.spinics.net/lists/linux-fsdevel/msg63807.html ("hfsplus volume suddenly inaccessable after 'hfs: recoff %d too large'") Sasha Levin, Feb 2015 http://lkml.org/lkml/2015/2/20/85 ("use after free") https://bugs.launchpad.net/ubuntu/+source/linux/+bug/740814 https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1027887 https://bugzilla.kernel.org/show_bug.cgi?id=42342 https://bugzilla.kernel.org/show_bug.cgi?id=63841 https://bugzilla.kernel.org/show_bug.cgi?id=78761 [2]: http://git.kernel.org/cgit/linux/kernel/git/tglx/history.git/commit/\ fs/hfs/bnode.c?id=d1081202f1d0ee35ab0beb490da4b65d4bc763db commit d1081202f1d0ee35ab0beb490da4b65d4bc763db Author: Andrew Morton <akpm@osdl.org> Date: Wed Feb 25 16:17:36 2004 -0800 [PATCH] HFS rewrite http://git.kernel.org/cgit/linux/kernel/git/tglx/history.git/commit/\ fs/hfsplus/bnode.c?id=91556682e0bf004d98a529bf829d339abb98bbbd commit 91556682e0bf004d98a529bf829d339abb98bbbd Author: Andrew Morton <akpm@osdl.org> Date: Wed Feb 25 16:17:48 2004 -0800 [PATCH] HFS+ support [3]: http://sourceforge.net/projects/linux-hfsplus/ http://sourceforge.net/projects/linux-hfsplus/files/Linux%202.4.x%20patch/hfsplus%200.1/ http://sourceforge.net/projects/linux-hfsplus/files/Linux%202.4.x%20patch/hfsplus%200.2/ http://linux-hfsplus.cvs.sourceforge.net/viewvc/linux-hfsplus/linux/\ fs/hfsplus/bnode.c?r1=1.4&r2=1.5 Date: Thu Jun 6 09:45:14 2002 +0000 Use buffer cache instead of page cache in bnode.c. Cache inode extents. [4]: http://git.kernel.org/cgit/linux/kernel/git/\ stable/linux-stable.git/commit/?id=a5e3985fa014029eb6795664c704953720cc7f7d commit a5e3985fa014029eb6795664c704953720cc7f7d Author: Roman Zippel <zippel@linux-m68k.org> Date: Tue Sep 6 15:18:47 2005 -0700 [PATCH] hfs: remove debug code Signed-off-by: Hin-Tak Leung <htl10@users.sourceforge.net> Signed-off-by: Sergei Antonov <saproj@gmail.com> Reviewed-by: Anton Altaparmakov <anton@tuxera.com> Reported-by: Sasha Levin <sasha.levin@oracle.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@infradead.org> Cc: Vyacheslav Dubeyko <slava@dubeyko.com> Cc: Sougata Santra <sougata@tuxera.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-10fs/coda: fix readlink buffer overflowJan Harkes
Dan Carpenter discovered a buffer overflow in the Coda file system readlink code. A userspace file system daemon can return a 4096 byte result which then triggers a one byte write past the allocated readlink result buffer. This does not trigger with an unmodified Coda implementation because Coda has a 1024 byte limit for symbolic links, however other userspace file systems using the Coda kernel module could be affected. Although this is an obvious overflow, I don't think this has to be handled as too sensitive from a security perspective because the overflow is on the Coda userspace daemon side which already needs root to open Coda's kernel device and to mount the file system before we get to the point that links can be read. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Jan Harkes <jaharkes@cs.cmu.edu> Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-10proc: convert to kstrto*()/kstrto*_from_user()Alexey Dobriyan
Convert from manual allocation/copy_from_user/... to kstrto*() family which were designed for exactly that. One case can not be converted to kstrto*_from_user() to make code even more simpler because of whitespace stripping, oh well... Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-10proc: change proc_subdir_lock to a rwlockWaiman Long
The proc_subdir_lock spinlock is used to allow only one task to make change to the proc directory structure as well as looking up information in it. However, the information lookup part can actually be entered by more than one task as the pde_get() and pde_put() reference count update calls in the critical sections are atomic increment and decrement respectively and so are safe with concurrent updates. The x86 architecture has already used qrwlock which is fair and other architectures like ARM are in the process of switching to qrwlock. So unfairness shouldn't be a concern in that conversion. This patch changed the proc_subdir_lock to a rwlock in order to enable concurrent lookup. The following functions were modified to take a write lock: - proc_register() - remove_proc_entry() - remove_proc_subtree() The following functions were modified to take a read lock: - xlate_proc_name() - proc_lookup_de() - proc_readdir_de() A parallel /proc filesystem search with the "find" command (1000 threads) was run on a 4-socket Haswell-EX box (144 threads). Before the patch, the parallel search took about 39s. After the patch, the parallel find took only 25s, a saving of about 14s. The micro-benchmark that I used was artificial, but it was used to reproduce an exit hanging problem that I saw in real application. In fact, only allow one task to do a lookup seems too limiting to me. Signed-off-by: Waiman Long <Waiman.Long@hp.com> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Nicolas Dichtel <nicolas.dichtel@6wind.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Scott J Norton <scott.norton@hp.com> Cc: Douglas Hatch <doug.hatch@hp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-10procfs: always expose /proc/<pid>/map_files/ and make it readableCalvin Owens
Currently, /proc/<pid>/map_files/ is restricted to CAP_SYS_ADMIN, and is only exposed if CONFIG_CHECKPOINT_RESTORE is set. Each mapped file region gets a symlink in /proc/<pid>/map_files/ corresponding to the virtual address range at which it is mapped. The symlinks work like the symlinks in /proc/<pid>/fd/, so you can follow them to the backing file even if that backing file has been unlinked. Currently, files which are mapped, unlinked, and closed are impossible to stat() from userspace. Exposing /proc/<pid>/map_files/ closes this functionality "hole". Not being able to stat() such files makes noticing and explicitly accounting for the space they use on the filesystem impossible. You can work around this by summing up the space used by every file in the filesystem and subtracting that total from what statfs() tells you, but that obviously isn't great, and it becomes unworkable once your filesystem becomes large enough. This patch moves map_files/ out from behind CONFIG_CHECKPOINT_RESTORE, and adjusts the permissions enforced on it as follows: * proc_map_files_lookup() * proc_map_files_readdir() * map_files_d_revalidate() Remove the CAP_SYS_ADMIN restriction, leaving only the current restriction requiring PTRACE_MODE_READ. The information made available to userspace by these three functions is already available in /proc/PID/maps with MODE_READ, so I don't see any reason to limit them any further (see below for more detail). * proc_map_files_follow_link() This stub has been added, and requires that the user have CAP_SYS_ADMIN in order to follow the links in map_files/, since there was concern on LKML both about the potential for bypassing permissions on ancestor directories in the path to files pointed to, and about what happens with more exotic memory mappings created by some drivers (ie dma-buf). In older versions of this patch, I changed every permission check in the four functions above to enforce MODE_ATTACH instead of MODE_READ. This was an oversight on my part, and after revisiting the discussion it seems that nobody was concerned about anything outside of what is made possible by ->follow_link(). So in this version, I've left the checks for PTRACE_MODE_READ as-is. [akpm@linux-foundation.org: catch up with concurrent proc_pid_follow_link() changes] Signed-off-by: Calvin Owens <calvinowens@fb.com> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Joe Perches <joe@perches.com> Cc: Kirill A. Shutemov <kirill@shutemov.name> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-10proc: add cond_resched to /proc/kpage* read/write loopVladimir Davydov
Reading/writing a /proc/kpage* file may take long on machines with a lot of RAM installed. Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Suggested-by: Andres Lagar-Cavilla <andreslc@google.com> Reviewed-by: Andres Lagar-Cavilla <andreslc@google.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Greg Thelen <gthelen@google.com> Cc: Michel Lespinasse <walken@google.com> Cc: David Rientjes <rientjes@google.com> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-10proc: export idle flag via kpageflagsVladimir Davydov
As noted by Minchan, a benefit of reading idle flag from /proc/kpageflags is that one can easily filter dirty and/or unevictable pages while estimating the size of unused memory. Note that idle flag read from /proc/kpageflags may be stale in case the page was accessed via a PTE, because it would be too costly to iterate over all page mappings on each /proc/kpageflags read to provide an up-to-date value. To make sure the flag is up-to-date one has to read /sys/kernel/mm/page_idle/bitmap first. Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Reviewed-by: Andres Lagar-Cavilla <andreslc@google.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Greg Thelen <gthelen@google.com> Cc: Michel Lespinasse <walken@google.com> Cc: David Rientjes <rientjes@google.com> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-10mm: introduce idle page trackingVladimir Davydov
Knowing the portion of memory that is not used by a certain application or memory cgroup (idle memory) can be useful for partitioning the system efficiently, e.g. by setting memory cgroup limits appropriately. Currently, the only means to estimate the amount of idle memory provided by the kernel is /proc/PID/{clear_refs,smaps}: the user can clear the access bit for all pages mapped to a particular process by writing 1 to clear_refs, wait for some time, and then count smaps:Referenced. However, this method has two serious shortcomings: - it does not count unmapped file pages - it affects the reclaimer logic To overcome these drawbacks, this patch introduces two new page flags, Idle and Young, and a new sysfs file, /sys/kernel/mm/page_idle/bitmap. A page's Idle flag can only be set from userspace by setting bit in /sys/kernel/mm/page_idle/bitmap at the offset corresponding to the page, and it is cleared whenever the page is accessed either through page tables (it is cleared in page_referenced() in this case) or using the read(2) system call (mark_page_accessed()). Thus by setting the Idle flag for pages of a particular workload, which can be found e.g. by reading /proc/PID/pagemap, waiting for some time to let the workload access its working set, and then reading the bitmap file, one can estimate the amount of pages that are not used by the workload. The Young page flag is used to avoid interference with the memory reclaimer. A page's Young flag is set whenever the Access bit of a page table entry pointing to the page is cleared by writing to the bitmap file. If page_referenced() is called on a Young page, it will add 1 to its return value, therefore concealing the fact that the Access bit was cleared. Note, since there is no room for extra page flags on 32 bit, this feature uses extended page flags when compiled on 32 bit. [akpm@linux-foundation.org: fix build] [akpm@linux-foundation.org: kpageidle requires an MMU] [akpm@linux-foundation.org: decouple from page-flags rework] Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Reviewed-by: Andres Lagar-Cavilla <andreslc@google.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Greg Thelen <gthelen@google.com> Cc: Michel Lespinasse <walken@google.com> Cc: David Rientjes <rientjes@google.com> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-10proc: add kpagecgroup fileVladimir Davydov
/proc/kpagecgroup contains a 64-bit inode number of the memory cgroup each page is charged to, indexed by PFN. Having this information is useful for estimating a cgroup working set size. The file is present if CONFIG_PROC_PAGE_MONITOR && CONFIG_MEMCG. Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Reviewed-by: Andres Lagar-Cavilla <andreslc@google.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Greg Thelen <gthelen@google.com> Cc: Michel Lespinasse <walken@google.com> Cc: David Rientjes <rientjes@google.com> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-09fix ufs write vs readpage race when writing into a holeAl Viro
Followup to the UFS series - with the way we clear the new blocks (via buffer cache, possibly on more than a page worth of file) we really should not insert a reference to new block into inode block tree until after we'd cleared it. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-09Merge branch 'for-next' of git://git.samba.org/sfrench/cifs-2.6Linus Torvalds
Pull cifs updates from Steve French: "Small cifs fix and a patch for improved debugging" * 'for-next' of git://git.samba.org/sfrench/cifs-2.6: cifs: Fix use-after-free on mid_q_entry Update cifs version number Add way to query server fs info for smb3
2015-09-09dax: update PMD fault handler with PMEM APIRoss Zwisler
As part of the v4.3 merge window the DAX code was updated by Matthew and Kirill to handle PMD pages. Also as part of the v4.3 merge window we updated the DAX code to do proper PMEM flushing (commit 2765cfbb342c: "dax: update I/O path to do proper PMEM flushing"). The additional code added by the DAX PMD patches also needs to be updated to properly use the PMEM API. This ensures that after a PMD fault is handled the zeros written to the newly allocated pages are durable on the DIMMs. linux/dax.h is included to get rid of a bunch of sparse warnings. Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com> Cc: Matthew Wilcox <willy@linux.intel.com>, Cc: Dan Williams <dan.j.williams@intel.com> Cc: Kirill Shutemov <kirill@shutemov.name> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-09ceph: improve readahead for file holesYan, Zheng
When readahead encounters file holes, osd reply returns error -ENOENT, finish_read() skips adding pages to the the page cache. So readahead does not work for file holes. The fix is adding zero pages to the page cache when -ENOENT is returned. Signed-off-by: Yan, Zheng <zyan@redhat.com>
2015-09-09ceph: get inode size for each append writeYan, Zheng
Signed-off-by: Yan, Zheng <zyan@redhat.com>
2015-09-09Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge second patch-bomb from Andrew Morton: "Almost all of the rest of MM. There was an unusually large amount of MM material this time" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (141 commits) zpool: remove no-op module init/exit mm: zbud: constify the zbud_ops mm: zpool: constify the zpool_ops mm: swap: zswap: maybe_preload & refactoring zram: unify error reporting zsmalloc: remove null check from destroy_handle_cache() zsmalloc: do not take class lock in zs_shrinker_count() zsmalloc: use class->pages_per_zspage zsmalloc: consider ZS_ALMOST_FULL as migrate source zsmalloc: partial page ordering within a fullness_list zsmalloc: use shrinker to trigger auto-compaction zsmalloc: account the number of compacted pages zsmalloc/zram: introduce zs_pool_stats api zsmalloc: cosmetic compaction code adjustments zsmalloc: introduce zs_can_compact() function zsmalloc: always keep per-class stats zsmalloc: drop unused variable `nr_to_migrate' mm/memblock.c: fix comment in __next_mem_range() mm/page_alloc.c: fix type information of memoryless node memory-hotplug: fix comments in zone_spanned_pages_in_node() and zone_spanned_pages_in_node() ...
2015-09-08Merge tag 'regmap-v4.3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap Pull regmap updates from Mark Brown: "This has been a busy release for regmap. By far the biggest set of changes here are those from Markus Pargmann which implement support for block transfers in smbus devices. This required quite a bit of refactoring but leaves us better able to handle odd restrictions that controllers may have and with better performance on smbus. Other new features include: - Fix interactions with lockdep for nested regmaps (eg, when a device using regmap is connected to a bus where the bus controller has a separate regmap). Lockdep's default class identification is too crude to work without help. - Support for must write bitfield operations, useful for operations which require writing a bit to trigger them from Kuniori Morimoto. - Support for delaying during register patch application from Nariman Poushin. - Support for overriding cache state via the debugfs implementation from Richard Fitzgerald" * tag 'regmap-v4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap: (25 commits) regmap: fix a NULL pointer dereference in __regmap_init regmap: Support bulk reads for devices without raw formatting regmap-i2c: Add smbus i2c block support regmap: Add raw_write/read checks for max_raw_write/read sizes regmap: regmap max_raw_read/write getter functions regmap: Introduce max_raw_read/write for regmap_bulk_read/write regmap: Add missing comments about struct regmap_bus regmap: No multi_write support if bus->write does not exist regmap: Split use_single_rw internally into use_single_read/write regmap: Fix regmap_bulk_write for bus writes regmap: regmap_raw_read return error on !bus->read regulator: core: Print at debug level on debugfs creation failure regmap: Fix regmap_can_raw_write check regmap: fix typos in regmap.c regmap: Fix integertypes for register address and value regmap: Move documentation to regmap.h regmap: Use different lockdep class for each regmap init call thermal: sti: Add parentheses around bridge->ops->regmap_init call mfd: vexpress: Add parentheses around bridge->ops->regmap_init call regmap: debugfs: Fix misuse of IS_ENABLED ...
2015-09-08hugetlbfs: add hugetlbfs_fallocate()Mike Kravetz
This is based on the shmem version, but it has diverged quite a bit. We have no swap to worry about, nor the new file sealing. Add synchronication via the fault mutex table to coordinate page faults, fallocate allocation and fallocate hole punch. What this allows us to do is move physical memory in and out of a hugetlbfs file without having it mapped. This also gives us the ability to support MADV_REMOVE since it is currently implemented using fallocate(). MADV_REMOVE lets madvise() remove pages from the middle of a hugetlbfs file, which wasn't possible before. hugetlbfs fallocate only operates on whole huge pages. Based on code by Dave Hansen. Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com> Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Acked-by: Hillf Danton <hillf.zj@alibaba-inc.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Rientjes <rientjes@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Aneesh Kumar <aneesh.kumar@linux.vnet.ibm.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Michal Hocko <mhocko@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-08hugetlbfs: truncate_hugepages() takes a range of pagesMike Kravetz
Modify truncate_hugepages() to take a range of pages (start, end) instead of simply start. If an end value of LLONG_MAX is passed, the current "truncate" functionality is maintained. Existing callers are modified to pass LLONG_MAX as end of range. By keying off end == LLONG_MAX, the routine behaves differently for truncate and hole punch. Page removal is now synchronized with page allocation via faults by using the fault mutex table. The hole punch case can experience the rare region_del error and must handle accordingly. Add the routine hugetlb_fix_reserve_counts to fix up reserve counts in the case where region_del returns an error. Since the routine handles more than just the truncate case, it is renamed to remove_inode_hugepages(). To be consistent, the routine truncate_huge_page() is renamed remove_huge_page(). Downstream of remove_inode_hugepages(), the routine hugetlb_unreserve_pages() is also modified to take a range of pages. hugetlb_unreserve_pages is modified to detect an error from region_del and pass it back to the caller. Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com> Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Acked-by: Hillf Danton <hillf.zj@alibaba-inc.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Rientjes <rientjes@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Aneesh Kumar <aneesh.kumar@linux.vnet.ibm.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Michal Hocko <mhocko@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-08hugetlbfs: hugetlb_vmtruncate_list() needs to take a range to deleteMike Kravetz
fallocate hole punch will want to unmap a specific range of pages. Modify the existing hugetlb_vmtruncate_list() routine to take a start/end range. If end is 0, this indicates all pages after start should be unmapped. This is the same as the existing truncate functionality. Modify existing callers to add 0 as end of range. Since the routine will be used in hole punch as well as truncate operations, it is more appropriately renamed to hugetlb_vmdelete_list(). Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com> Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Acked-by: Hillf Danton <hillf.zj@alibaba-inc.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Rientjes <rientjes@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Aneesh Kumar <aneesh.kumar@linux.vnet.ibm.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Michal Hocko <mhocko@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-08mm: /proc/pid/smaps:: show proportional swap share of the mappingMinchan Kim
We want to know per-process workingset size for smart memory management on userland and we use swap(ex, zram) heavily to maximize memory efficiency so workingset includes swap as well as RSS. On such system, if there are lots of shared anonymous pages, it's really hard to figure out exactly how many each process consumes memory(ie, rss + wap) if the system has lots of shared anonymous memory(e.g, android). This patch introduces SwapPss field on /proc/<pid>/smaps so we can get more exact workingset size per process. Bongkyu tested it. Result is below. 1. 50M used swap SwapTotal: 461976 kB SwapFree: 411192 kB $ adb shell cat /proc/*/smaps | grep "SwapPss:" | awk '{sum += $2} END {print sum}'; 48236 $ adb shell cat /proc/*/smaps | grep "Swap:" | awk '{sum += $2} END {print sum}'; 141184 2. 240M used swap SwapTotal: 461976 kB SwapFree: 216808 kB $ adb shell cat /proc/*/smaps | grep "SwapPss:" | awk '{sum += $2} END {print sum}'; 230315 $ adb shell cat /proc/*/smaps | grep "Swap:" | awk '{sum += $2} END {print sum}'; 1387744 [akpm@linux-foundation.org: simplify kunmap_atomic() call] Signed-off-by: Minchan Kim <minchan@kernel.org> Reported-by: Bongkyu Kim <bongkyu.kim@lge.com> Tested-by: Bongkyu Kim <bongkyu.kim@lge.com> Cc: Hugh Dickins <hughd@google.com> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Jerome Marchand <jmarchan@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-08pagemap: add mmap-exclusive bit for marking pages mapped only hereKonstantin Khlebnikov
This patch sets bit 56 in pagemap if this page is mapped only once. It allows to detect exclusively used pages without exposing PFN: present file exclusive state 0 0 0 non-present 1 1 0 file page mapped somewhere else 1 1 1 file page mapped only here 1 0 0 anon non-CoWed page (shared with parent/child) 1 0 1 anon CoWed page (or never forked) CoWed pages in (MAP_FILE | MAP_PRIVATE) areas are anon in this context. MMap-exclusive bit doesn't reflect potential page-sharing via swapcache: page could be mapped once but has several swap-ptes which point to it. Application could detect that by swap bit in pagemap entry and touch that pte via /proc/pid/mem to get real information. See http://lkml.kernel.org/r/CAEVpBa+_RyACkhODZrRvQLs80iy0sqpdrd0AaP_-tgnX3Y9yNQ@mail.gmail.com Requested by Mark Williamson. [akpm@linux-foundation.org: fix spello] Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Reviewed-by: Mark Williamson <mwilliamson@undo-software.com> Tested-by: Mark Williamson <mwilliamson@undo-software.com> Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-08pagemap: hide physical addresses from non-privileged usersKonstantin Khlebnikov
This patch makes pagemap readable for normal users and hides physical addresses from them. For some use-cases PFN isn't required at all. See http://lkml.kernel.org/r/1425935472-17949-1-git-send-email-kirill@shutemov.name Fixes: ab676b7d6fbf ("pagemap: do not leak physical addresses to non-privileged userspace") Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Reviewed-by: Mark Williamson <mwilliamson@undo-software.com> Tested-by: Mark Williamson <mwilliamson@undo-software.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-08pagemap: rework hugetlb and thp reportKonstantin Khlebnikov
This patch moves pmd dissection out of reporting loop: huge pages are reported as bunch of normal pages with contiguous PFNs. Add missing "FILE" bit in hugetlb vmas. Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Reviewed-by: Mark Williamson <mwilliamson@undo-software.com> Tested-by: Mark Williamson <mwilliamson@undo-software.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-08pagemap: switch to the new format and do some cleanupKonstantin Khlebnikov
This patch removes page-shift bits (scheduled to remove since 3.11) and completes migration to the new bit layout. Also it cleans messy macro. Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Mark Williamson <mwilliamson@undo-software.com> Tested-by: Mark Williamson <mwilliamson@undo-software.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>