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2015-02-08mmc: sdhci: add support for realtek rts5250Micky Ching
commit 9107ebbf9652c033eb5dd10a6ea34a132db3cde1 upstream. Add support for realtek rts5250 pci card reader. The card reader has some problems with DDR50 mode, so add a new quirks2 for broken ddr50. Signed-off-by: Micky Ching <micky_ching@realsil.com.cn> Signed-off-by: Chris Ball <chris@printf.net> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2015-02-08mmc: sdhci: add quirk for broken HS200 supportDavid Cohen
commit 13868bf20f2f2c305f96e23620b024e167d6f9cb upstream. This patch defines a quirk for platforms unable to enable HS200 support. Signed-off-by: David Cohen <david.a.cohen@linux.intel.com> Reviewed-by: Chuanxiao Dong <chuanxiao.dong@intel.com> Acked-by: Dong Aisheng <b29396@freescale.com> Cc: stable <stable@vger.kernel.org> # [3.13] Signed-off-by: Chris Ball <chris@printf.net> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2015-02-02ipc/compat_sys_msgrcv: change msgtyp type from long to compat_long_tHeiko Carstens
commit 291fdb0bcebd5e8db6af767c1fdc522167dad73d upstream. Change the type of compat_sys_msgrcv's msgtyp parameter from long to compat_long_t, since compat user space passes only a 32 bit signed value. Let the compat wrapper do proper sign extension to 64 bit of this parameter. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2015-01-29move d_rcu from overlapping d_child to overlapping d_aliasAl Viro
commit 946e51f2bf37f1656916eb75bd0742ba33983c28 upstream. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Acked-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2015-01-29mm: get rid of radix tree gfp mask for pagecache_get_pageMichal Hocko
commit 45f87de57f8fad59302fd263dd81ffa4843b5b24 upstream. Commit 2457aec63745 ("mm: non-atomically mark page accessed during page cache allocation where possible") has added a separate parameter for specifying gfp mask for radix tree allocations. Not only this is less than optimal from the API point of view because it is error prone, it is also buggy currently because grab_cache_page_write_begin is using GFP_KERNEL for radix tree and if fgp_flags doesn't contain FGP_NOFS (mostly controlled by fs by AOP_FLAG_NOFS flag) but the mapping_gfp_mask has __GFP_FS cleared then the radix tree allocation wouldn't obey the restriction and might recurse into filesystem and cause deadlocks. This is the case for most filesystems unfortunately because only ext4 and gfs2 are using AOP_FLAG_NOFS. Let's simply remove radix_gfp_mask parameter because the allocation context is same for both page cache and for the radix tree. Just make sure that the radix tree gets only the sane subset of the mask (e.g. do not pass __GFP_WRITE). Long term it is more preferable to convert remaining users of AOP_FLAG_NOFS to use mapping_gfp_mask instead and simplify this interface even further. Reported-by: Dave Chinner <david@fromorbit.com> Signed-off-by: Michal Hocko <mhocko@suse.cz> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2015-01-29crypto: prefix module autoloading with "crypto-"Kees Cook
commit 5d26a105b5a73e5635eae0629b42fa0a90e07b7b upstream. This prefixes all crypto module loading with "crypto-" so we never run the risk of exposing module auto-loading to userspace via a crypto API, as demonstrated by Mathias Krause: https://lkml.org/lkml/2013/3/4/70 Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2015-01-29time: settimeofday: Validate the values of tv from userSasha Levin
commit 6ada1fc0e1c4775de0e043e1bd3ae9d065491aa5 upstream. An unvalidated user input is multiplied by a constant, which can result in an undefined behaviour for large values. While this is validated later, we should avoid triggering undefined behaviour. Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com> [jstultz: include trivial milisecond->microsecond correction noticed by Andy] Signed-off-by: John Stultz <john.stultz@linaro.org> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2015-01-26genirq: Prevent proc race against freeing of irq descriptorsThomas Gleixner
commit c291ee622165cb2c8d4e7af63fffd499354a23be upstream. Since the rework of the sparse interrupt code to actually free the unused interrupt descriptors there exists a race between the /proc interfaces to the irq subsystem and the code which frees the interrupt descriptor. CPU0 CPU1 show_interrupts() desc = irq_to_desc(X); free_desc(desc) remove_from_radix_tree(); kfree(desc); raw_spinlock_irq(&desc->lock); /proc/interrupts is the only interface which can actively corrupt kernel memory via the lock access. /proc/stat can only read from freed memory. Extremly hard to trigger, but possible. The interfaces in /proc/irq/N/ are not affected by this because the removal of the proc file is serialized in procfs against concurrent readers/writers. The removal happens before the descriptor is freed. For architectures which have CONFIG_SPARSE_IRQ=n this is a non issue as the descriptor is never freed. It's merely cleared out with the irq descriptor lock held. So any concurrent proc access will either see the old correct value or the cleared out ones. Protect the lookup and access to the irq descriptor in show_interrupts() with the sparse_irq_lock. Provide kstat_irqs_usr() which is protecting the lookup and access with sparse_irq_lock and switch /proc/stat to use it. Document the existing kstat_irqs interfaces so it's clear that the caller needs to take care about protection. The users of these interfaces are either not affected due to SPARSE_IRQ=n or already protected against removal. Fixes: 1f5a5b87f78f "genirq: Implement a sane sparse_irq allocator" Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2015-01-26mm: propagate error from stack expansion even for guard pageLinus Torvalds
commit fee7e49d45149fba60156f5b59014f764d3e3728 upstream. Jay Foad reports that the address sanitizer test (asan) sometimes gets confused by a stack pointer that ends up being outside the stack vma that is reported by /proc/maps. This happens due to an interaction between RLIMIT_STACK and the guard page: when we do the guard page check, we ignore the potential error from the stack expansion, which effectively results in a missing guard page, since the expected stack expansion won't have been done. And since /proc/maps explicitly ignores the guard page (commit d7824370e263: "mm: fix up some user-visible effects of the stack guard page"), the stack pointer ends up being outside the reported stack area. This is the minimal patch: it just propagates the error. It also effectively makes the guard page part of the stack limit, which in turn measn that the actual real stack is one page less than the stack limit. Let's see if anybody notices. We could teach acct_stack_growth() to allow an extra page for a grow-up/grow-down stack in the rlimit test, but I don't want to add more complexity if it isn't needed. Reported-and-tested-by: Jay Foad <jay.foad@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2015-01-26pstore-ram: Allow optional mapping with pgprot_noncachedTony Lindgren
commit 027bc8b08242c59e19356b4b2c189f2d849ab660 upstream. On some ARMs the memory can be mapped pgprot_noncached() and still be working for atomic operations. As pointed out by Colin Cross <ccross@android.com>, in some cases you do want to use pgprot_noncached() if the SoC supports it to see a debug printk just before a write hanging the system. On ARMs, the atomic operations on strongly ordered memory are implementation defined. So let's provide an optional kernel parameter for configuring pgprot_noncached(), and use pgprot_writecombine() by default. Cc: Arnd Bergmann <arnd@arndb.de> Cc: Rob Herring <robherring2@gmail.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Anton Vorontsov <anton@enomsg.org> Cc: Colin Cross <ccross@android.com> Cc: Olof Johansson <olof@lixom.net> Cc: Russell King <linux@arm.linux.org.uk> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2015-01-07audit: restore AUDIT_LOGINUID unset ABIRichard Guy Briggs
commit 041d7b98ffe59c59fdd639931dea7d74f9aa9a59 upstream. A regression was caused by commit 780a7654cee8: audit: Make testing for a valid loginuid explicit. (which in turn attempted to fix a regression caused by e1760bd) When audit_krule_to_data() fills in the rules to get a listing, there was a missing clause to convert back from AUDIT_LOGINUID_SET to AUDIT_LOGINUID. This broke userspace by not returning the same information that was sent and expected. The rule: auditctl -a exit,never -F auid=-1 gives: auditctl -l LIST_RULES: exit,never f24=0 syscall=all when it should give: LIST_RULES: exit,never auid=-1 (0xffffffff) syscall=all Tag it so that it is reported the same way it was set. Create a new private flags audit_krule field (pflags) to store it that won't interact with the public one from the API. Signed-off-by: Richard Guy Briggs <rgb@redhat.com> Signed-off-by: Paul Moore <pmoore@redhat.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2015-01-07userns: Add a knob to disable setgroups on a per user namespace basisEric W. Biederman
commit 9cc46516ddf497ea16e8d7cb986ae03a0f6b92f8 upstream. - Expose the knob to user space through a proc file /proc/<pid>/setgroups A value of "deny" means the setgroups system call is disabled in the current processes user namespace and can not be enabled in the future in this user namespace. A value of "allow" means the segtoups system call is enabled. - Descendant user namespaces inherit the value of setgroups from their parents. - A proc file is used (instead of a sysctl) as sysctls currently do not allow checking the permissions at open time. - Writing to the proc file is restricted to before the gid_map for the user namespace is set. This ensures that disabling setgroups at a user namespace level will never remove the ability to call setgroups from a process that already has that ability. A process may opt in to the setgroups disable for itself by creating, entering and configuring a user namespace or by calling setns on an existing user namespace with setgroups disabled. Processes without privileges already can not call setgroups so this is a noop. Prodcess with privilege become processes without privilege when entering a user namespace and as with any other path to dropping privilege they would not have the ability to call setgroups. So this remains within the bounds of what is possible without a knob to disable setgroups permanently in a user namespace. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2015-01-07userns: Don't allow setgroups until a gid mapping has been setablishedEric W. Biederman
commit 273d2c67c3e179adb1e74f403d1e9a06e3f841b5 upstream. setgroups is unique in not needing a valid mapping before it can be called, in the case of setgroups(0, NULL) which drops all supplemental groups. The design of the user namespace assumes that CAP_SETGID can not actually be used until a gid mapping is established. Therefore add a helper function to see if the user namespace gid mapping has been established and call that function in the setgroups permission check. This is part of the fix for CVE-2014-8989, being able to drop groups without privilege using user namespaces. Reviewed-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2015-01-07groups: Consolidate the setgroups permission checksEric W. Biederman
commit 7ff4d90b4c24a03666f296c3d4878cd39001e81e upstream. Today there are 3 instances of setgroups and due to an oversight their permission checking has diverged. Add a common function so that they may all share the same permission checking code. This corrects the current oversight in the current permission checks and adds a helper to avoid this in the future. A user namespace security fix will update this new helper, shortly. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2014-12-06iio: Fix IIO_EVENT_CODE_EXTRACT_DIR bit maskCristina Ciocan
commit ccf54555da9a5e91e454b909ca6a5303c7d6b910 upstream. The direction field is set on 7 bits, thus we need to AND it with 0111 111 mask in order to retrieve it, that is 0x7F, not 0xCF as it is now. Fixes: ade7ef7ba (staging:iio: Differential channel handling) Signed-off-by: Cristina Ciocan <cristina.ciocan@intel.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2014-12-06PCI/MSI: Add device flag indicating that 64-bit MSIs don't workBenjamin Herrenschmidt
commit f144d1496b47e7450f41b767d0d91c724c2198bc upstream. This can be set by quirks/drivers to be used by the architecture code that assigns the MSI addresses. We additionally add verification in the core MSI code that the values assigned by the architecture do satisfy the limitation in order to fail gracefully if they don't (ie. the arch hasn't been updated to deal with that quirk yet). Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2014-12-06Input: serio - add firmware_id sysfs attributeHans de Goede
commit 0456c66f4e905e1ca839318219c770988b47975c upstream. serio devices exposed via platform firmware interfaces such as ACPI may provide additional identifying information of use to userspace. We don't associate the serio devices with the firmware device (we don't set it as parent), so there's no way for userspace to make use of this information. We cannot change the parent for serio devices instantiated though a firmware interface as that would break suspend / resume ordering. Therefore this patch adds a new firmware_id sysfs attribute so that userspace can get a string from there with any additional identifying information the firmware interface may provide. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Acked-by: Peter Hutterer <peter.hutterer@who-t.net> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2014-12-03ext4: atomically set inode->i_flags in ext4_set_inode_flags()Theodore Ts'o
commit 5f16f3225b06242a9ee876f07c1c9b6ed36a22b6 upstream. Use cmpxchg() to atomically set i_flags instead of clearing out the S_IMMUTABLE, S_APPEND, etc. flags and then setting them from the EXT4_IMMUTABLE_FL, EXT4_APPEND_FL flags, since this opens up a race where an immutable file has the immutable flag cleared for a brief window of time. js: there is no change for ext4. This patch defines merely inode_set_flags for jffs in the next patch. I wonder why do we have both inode_set_flags and set_mask_bits? Looks like an improperly resolved merge conflict. Reported-by: John Sullivan <jsrhbz@kanargh.force9.co.uk> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: stable@kernel.org Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2014-12-03fix O_SYNC|O_APPEND syncing the wrong range on write()Al Viro
commit d311d79de305f1ada47cadd672e6ed1b28a949eb upstream. It actually goes back to 2004 ([PATCH] Concurrent O_SYNC write support) when sync_page_range() had been introduced; generic_file_write{,v}() correctly synced pos_after_write - written .. pos_after_write - 1 but generic_file_aio_write() synced pos_before_write .. pos_before_write + written - 1 instead. Which is not the same thing with O_APPEND, obviously. A couple of years later correct variant had been killed off when everything switched to use of generic_file_aio_write(). All users of generic_file_aio_write() are affected, and the same bug has been copied into other instances of ->aio_write(). The fix is trivial; the only subtle point is that generic_write_sync() ought to be inlined to avoid calculations useless for the majority of calls. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2014-11-27inetdevice: fixed signed integer overflowVincent BENAYOUN
[ Upstream commit 84bc88688e3f6ef843aa8803dbcd90168bb89faf ] There could be a signed overflow in the following code. The expression, (32-logmask) is comprised between 0 and 31 included. It may be equal to 31. In such a case the left shift will produce a signed integer overflow. According to the C99 Standard, this is an undefined behavior. A simple fix is to replace the signed int 1 with the unsigned int 1U. Signed-off-by: Vincent BENAYOUN <vincent.benayoun@trust-in-soft.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2014-11-19clocksource: Remove "weak" from clocksource_default_clock() declarationBjorn Helgaas
commit 96a2adbc6f501996418da9f7afe39bf0e4d006a9 upstream. kernel/time/jiffies.c provides a default clocksource_default_clock() definition explicitly marked "weak". arch/s390 provides its own definition intended to override the default, but the "weak" attribute on the declaration applied to the s390 definition as well, so the linker chose one based on link order (see 10629d711ed7 ("PCI: Remove __weak annotation from pcibios_get_phb_of_node decl")). Remove the "weak" attribute from the clocksource_default_clock() declaration so we always prefer a non-weak definition over the weak one, independent of link order. Fixes: f1b82746c1e9 ("clocksource: Cleanup clocksource selection") Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: John Stultz <john.stultz@linaro.org> Acked-by: Ingo Molnar <mingo@kernel.org> CC: Daniel Lezcano <daniel.lezcano@linaro.org> CC: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2014-11-19kgdb: Remove "weak" from kgdb_arch_pc() declarationBjorn Helgaas
commit 107bcc6d566cb40184068d888637f9aefe6252dd upstream. kernel/debug/debug_core.c provides a default kgdb_arch_pc() definition explicitly marked "weak". Several architectures provide their own definitions intended to override the default, but the "weak" attribute on the declaration applied to the arch definitions as well, so the linker chose one based on link order (see 10629d711ed7 ("PCI: Remove __weak annotation from pcibios_get_phb_of_node decl")). Remove the "weak" attribute from the declaration so we always prefer a non-weak definition over the weak one, independent of link order. Fixes: 688b744d8bc8 ("kgdb: fix signedness mixmatches, add statics, add declaration to header") Tested-by: Vineet Gupta <vgupta@synopsys.com> # for ARC build Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2014-11-19vmcore: Remove "weak" from function declarationsBjorn Helgaas
commit 5ab03ac5aaa1f032e071f1b3dc433b7839359c03 upstream. For the following functions: elfcorehdr_alloc() elfcorehdr_free() elfcorehdr_read() elfcorehdr_read_notes() remap_oldmem_pfn_range() fs/proc/vmcore.c provides default definitions explicitly marked "weak". arch/s390 provides its own definitions intended to override the default ones, but the "weak" attribute on the declarations applied to the s390 definitions as well, so the linker chose one based on link order (see 10629d711ed7 ("PCI: Remove __weak annotation from pcibios_get_phb_of_node decl")). Remove the "weak" attribute from the declarations so we always prefer a non-weak definition over the weak one, independent of link order. Fixes: be8a8d069e50 ("vmcore: introduce ELF header in new memory feature") Fixes: 9cb218131de1 ("vmcore: introduce remap_oldmem_pfn_range()") Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Vivek Goyal <vgoyal@redhat.com> CC: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2014-11-19nfs: fix pnfs direct write memory leakPeng Tao
commit 8c393f9a721c30a030049a680e1bf896669bb279 upstream. For pNFS direct writes, layout driver may dynamically allocate ds_cinfo.buckets. So we need to take care to free them when freeing dreq. Ideally this needs to be done inside layout driver where ds_cinfo.buckets are allocated. But buckets are attached to dreq and reused across LD IO iterations. So I feel it's OK to free them in the generic layer. Signed-off-by: Peng Tao <tao.peng@primarydata.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2014-11-13of: Fix overflow bug in string property parsing functionsGrant Likely
commit a87fa1d81a9fb5e9adca9820e16008c40ad09f33 upstream. The string property read helpers will run off the end of the buffer if it is handed a malformed string property. Rework the parsers to make sure that doesn't happen. At the same time add new test cases to make sure the functions behave themselves. The original implementations of of_property_read_string_index() and of_property_count_strings() both open-coded the same block of parsing code, each with it's own subtly different bugs. The fix here merges functions into a single helper and makes the original functions static inline wrappers around the helper. One non-bugfix aspect of this patch is the addition of a new wrapper, of_property_read_string_array(). The new wrapper is needed by the device_properties feature that Rafael is working on and planning to merge for v3.19. The implementation is identical both with and without the new static inline wrapper, so it just got left in to reduce the churn on the header file. Signed-off-by: Grant Likely <grant.likely@linaro.org> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Mika Westerberg <mika.westerberg@linux.intel.com> Cc: Rob Herring <robh+dt@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Darren Hart <darren.hart@intel.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2014-11-13HID: usbhid: add always-poll quirkJohan Hovold
commit 0b750b3baa2d64f1b77aecc10f20deeb28efe60d upstream. Add quirk to make sure that a device is always polled for input events even if it hasn't been opened. This is needed for devices that disconnects from the bus unless the interrupt endpoint has been polled at least once or when not responding to an input event (e.g. after having shut down X). Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2014-11-13USB: core: add device-qualifier quirkJohan Hovold
commit 2a159389bf5d962359349a76827b2f683276a1c7 upstream. Add new quirk for devices that cannot handle requests for the device_qualifier descriptor. A USB-2.0 compliant device must respond to requests for the device_qualifier descriptor (even if it's with a request error), but at least one device is known to misbehave after such a request. Suggested-by: Bjørn Mork <bjorn@mork.no> Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2014-11-13OOM, PM: OOM killed task shouldn't escape PM suspendMichal Hocko
commit 5695be142e203167e3cb515ef86a88424f3524eb upstream. PM freezer relies on having all tasks frozen by the time devices are getting frozen so that no task will touch them while they are getting frozen. But OOM killer is allowed to kill an already frozen task in order to handle OOM situtation. In order to protect from late wake ups OOM killer is disabled after all tasks are frozen. This, however, still keeps a window open when a killed task didn't manage to die by the time freeze_processes finishes. Reduce the race window by checking all tasks after OOM killer has been disabled. This is still not race free completely unfortunately because oom_killer_disable cannot stop an already ongoing OOM killer so a task might still wake up from the fridge and get killed without freeze_processes noticing. Full synchronization of OOM and freezer is, however, too heavy weight for this highly unlikely case. Introduce and check oom_kills counter which gets incremented early when the allocator enters __alloc_pages_may_oom path and only check all the tasks if the counter changes during the freezing attempt. The counter is updated so early to reduce the race window since allocator checked oom_killer_disabled which is set by PM-freezing code. A false positive will push the PM-freezer into a slow path but that is not a big deal. Changes since v1 - push the re-check loop out of freeze_processes into check_frozen_processes and invert the condition to make the code more readable as per Rafael Fixes: f660daac474c6f (oom: thaw threads if oom killed thread is frozen before deferring) Signed-off-by: Michal Hocko <mhocko@suse.cz> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2014-11-13block: fix alignment_offset math that assumes io_min is a power-of-2Mike Snitzer
commit b8839b8c55f3fdd60dc36abcda7e0266aff7985c upstream. The math in both blk_stack_limits() and queue_limit_alignment_offset() assume that a block device's io_min (aka minimum_io_size) is always a power-of-2. Fix the math such that it works for non-power-of-2 io_min. This issue (of alignment_offset != 0) became apparent when testing dm-thinp with a thinp blocksize that matches a RAID6 stripesize of 1280K. Commit fdfb4c8c1 ("dm thin: set minimum_io_size to pool's data block size") unlocked the potential for alignment_offset != 0 due to the dm-thin-pool's io_min possibly being a non-power-of-2. Signed-off-by: Mike Snitzer <snitzer@redhat.com> Acked-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Jens Axboe <axboe@fb.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2014-11-13random: add and use memzero_explicit() for clearing dataDaniel Borkmann
commit d4c5efdb97773f59a2b711754ca0953f24516739 upstream. zatimend has reported that in his environment (3.16/gcc4.8.3/corei7) memset() calls which clear out sensitive data in extract_{buf,entropy, entropy_user}() in random driver are being optimized away by gcc. Add a helper memzero_explicit() (similarly as explicit_bzero() variants) that can be used in such cases where a variable with sensitive data is being cleared out in the end. Other use cases might also be in crypto code. [ I have put this into lib/string.c though, as it's always built-in and doesn't need any dependencies then. ] Fixes kernel bugzilla: 82041 Reported-by: zatimend@hotmail.co.uk Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Cc: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2014-11-13vfs: fix data corruption when blocksize < pagesize for mmaped dataJan Kara
commit 90a8020278c1598fafd071736a0846b38510309c upstream. ->page_mkwrite() is used by filesystems to allocate blocks under a page which is becoming writeably mmapped in some process' address space. This allows a filesystem to return a page fault if there is not enough space available, user exceeds quota or similar problem happens, rather than silently discarding data later when writepage is called. However VFS fails to call ->page_mkwrite() in all the cases where filesystems need it when blocksize < pagesize. For example when blocksize = 1024, pagesize = 4096 the following is problematic: ftruncate(fd, 0); pwrite(fd, buf, 1024, 0); map = mmap(NULL, 1024, PROT_WRITE, MAP_SHARED, fd, 0); map[0] = 'a'; ----> page_mkwrite() for index 0 is called ftruncate(fd, 10000); /* or even pwrite(fd, buf, 1, 10000) */ mremap(map, 1024, 10000, 0); map[4095] = 'a'; ----> no page_mkwrite() called At the moment ->page_mkwrite() is called, filesystem can allocate only one block for the page because i_size == 1024. Otherwise it would create blocks beyond i_size which is generally undesirable. But later at ->writepage() time, we also need to store data at offset 4095 but we don't have block allocated for it. This patch introduces a helper function filesystems can use to have ->page_mkwrite() called at all the necessary moments. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2014-11-13crypto: more robust crypto_memneqCesar Eduardo Barros
commit fe8c8a126806fea4465c43d62a1f9d273a572bf5 upstream. [Only use the compiler.h portion of this patch, to get the OPTIMIZER_HIDE_VAR() macro, which we need for other -stable patches - gregkh] Disabling compiler optimizations can be fragile, since a new optimization could be added to -O0 or -Os that breaks the assumptions the code is making. Instead of disabling compiler optimizations, use a dummy inline assembly (based on RELOC_HIDE) to block the problematic kinds of optimization, while still allowing other optimizations to be applied to the code. The dummy inline assembly is added after every OR, and has the accumulator variable as its input and output. The compiler is forced to assume that the dummy inline assembly could both depend on the accumulator variable and change the accumulator variable, so it is forced to compute the value correctly before the inline assembly, and cannot assume anything about its value after the inline assembly. This change should be enough to make crypto_memneq work correctly (with data-independent timing) even if it is inlined at its call sites. That can be done later in a followup patch. Compile-tested on x86_64. Signed-off-by: Cesar Eduardo Barros <cesarb@cesarb.eti.br> Acked-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2014-10-31kernel: add support for gcc 5Sasha Levin
commit 71458cfc782eafe4b27656e078d379a34e472adf upstream. We're missing include/linux/compiler-gcc5.h which is required now because gcc branched off to v5 in trunk. Just copy the relevant bits out of include/linux/compiler-gcc4.h, no new code is added as of now. This fixes a build error when using gcc 5. Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2014-10-31mm: clear __GFP_FS when PF_MEMALLOC_NOIO is setJunxiao Bi
commit 934f3072c17cc8886f4c043b47eeeb1b12f8de33 upstream. commit 21caf2fc1931 ("mm: teach mm by current context info to not do I/O during memory allocation") introduces PF_MEMALLOC_NOIO flag to avoid doing I/O inside memory allocation, __GFP_IO is cleared when this flag is set, but __GFP_FS implies __GFP_IO, it should also be cleared. Or it may still run into I/O, like in superblock shrinker. And this will make the kernel run into the deadlock case described in that commit. See Dave Chinner's comment about io in superblock shrinker: Filesystem shrinkers do indeed perform IO from the superblock shrinker and have for years. Even clean inodes can require IO before they can be freed - e.g. on an orphan list, need truncation of post-eof blocks, need to wait for ordered operations to complete before it can be freed, etc. IOWs, Ext4, btrfs and XFS all can issue and/or block on arbitrary amounts of IO in the superblock shrinker context. XFS, in particular, has been doing transactions and IO from the VFS inode cache shrinker since it was first introduced.... Fix this by clearing __GFP_FS in memalloc_noio_flags(), this function has masked all the gfp_mask that will be passed into fs for the processes setting PF_MEMALLOC_NOIO in the direct reclaim path. v1 thread at: https://lkml.org/lkml/2014/9/3/32 Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com> Cc: Dave Chinner <david@fromorbit.com> Cc: joyce.xue <xuejiufei@huawei.com> Cc: Ming Lei <ming.lei@canonical.com> Cc: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2014-10-31kvm: fix potentially corrupt mmio cacheDavid Matlack
commit ee3d1570b58677885b4552bce8217fda7b226a68 upstream. vcpu exits and memslot mutations can run concurrently as long as the vcpu does not aquire the slots mutex. Thus it is theoretically possible for memslots to change underneath a vcpu that is handling an exit. If we increment the memslot generation number again after synchronize_srcu_expedited(), vcpus can safely cache memslot generation without maintaining a single rcu_dereference through an entire vm exit. And much of the x86/kvm code does not maintain a single rcu_dereference of the current memslots during each exit. We can prevent the following case: vcpu (CPU 0) | thread (CPU 1) --------------------------------------------+-------------------------- 1 vm exit | 2 srcu_read_unlock(&kvm->srcu) | 3 decide to cache something based on | old memslots | 4 | change memslots | (increments generation) 5 | synchronize_srcu(&kvm->srcu); 6 retrieve generation # from new memslots | 7 tag cache with new memslot generation | 8 srcu_read_unlock(&kvm->srcu) | ... | <action based on cache occurs even | though the caching decision was based | on the old memslots> | ... | <action *continues* to occur until next | memslot generation change, which may | be never> | | By incrementing the generation after synchronizing with kvm->srcu readers, we ensure that the generation retrieved in (6) will become invalid soon after (8). Keeping the existing increment is not strictly necessary, but we do keep it and just move it for consistency from update_memslots to install_new_memslots. It invalidates old cached MMIOs immediately, instead of having to wait for the end of synchronize_srcu_expedited, which makes the code more clearly correct in case CPU 1 is preempted right after synchronize_srcu() returns. To avoid halving the generation space in SPTEs, always presume that the low bit of the generation is zero when reconstructing a generation number out of an SPTE. This effectively disables MMIO caching in SPTEs during the call to synchronize_srcu_expedited. Using the low bit this way is somewhat like a seqcount---where the protected thing is a cache, and instead of retrying we can simply punt if we observe the low bit to be 1. Signed-off-by: David Matlack <dmatlack@google.com> Reviewed-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Reviewed-by: David Matlack <dmatlack@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2014-10-31pci_ids: Add support for Intel Quark ILBJosef Ahmad
commit bb048713bba3ead39f6112910906d9fe3f88ede7 upstream. This patch adds the PCI id for Intel Quark ILB. It will be used for GPIO and Multifunction device driver. Signed-off-by: Josef Ahmad <josef.ahmad@intel.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Lee Jones <lee.jones@linaro.org> Signed-off-by: Chang Rebecca Swee Fun <rebecca.swee.fun.chang@intel.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2014-10-30dentry_kill(): don't try to remove from shrink listAl Viro
commit 41edf278fc2f042f4e22a12ed87d19c5201210e1 upstream. If the victim in on the shrink list, don't remove it from there. If shrink_dentry_list() manages to remove it from the list before we are done - fine, we'll just free it as usual. If not - mark it with new flag (DCACHE_MAY_FREE) and leave it there. Eventually, shrink_dentry_list() will get to it, remove the sucker from shrink list and call dentry_kill(dentry, 0). Which is where we'll deal with freeing. Since now dentry_kill(dentry, 0) may happen after or during dentry_kill(dentry, 1), we need to recognize that (by seeing DCACHE_DENTRY_KILLED already set), unlock everything and either free the sucker (in case DCACHE_MAY_FREE has been set) or leave it for ongoing dentry_kill(dentry, 1) to deal with. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2014-10-30USB: Add device quirk for ASUS T100 Base Station keyboardLu Baolu
commit ddbe1fca0bcb87ca8c199ea873a456ca8a948567 upstream. This full-speed USB device generates spurious remote wakeup event as soon as USB_DEVICE_REMOTE_WAKEUP feature is set. As the result, Linux can't enter system suspend and S0ix power saving modes once this keyboard is used. This patch tries to introduce USB_QUIRK_IGNORE_REMOTE_WAKEUP quirk. With this quirk set, wakeup capability will be ignored during device configure. This patch could be back-ported to kernels as old as 2.6.39. Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2014-10-17USB: Add device quirk for ASUS T100 Base Station keyboardLu Baolu
commit ddbe1fca0bcb87ca8c199ea873a456ca8a948567 upstream. This full-speed USB device generates spurious remote wakeup event as soon as USB_DEVICE_REMOTE_WAKEUP feature is set. As the result, Linux can't enter system suspend and S0ix power saving modes once this keyboard is used. This patch tries to introduce USB_QUIRK_IGNORE_REMOTE_WAKEUP quirk. With this quirk set, wakeup capability will be ignored during device configure. This patch could be back-ported to kernels as old as 2.6.39. Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2014-10-17net: Always untag vlan-tagged traffic on input.Vlad Yasevich
[ Upstream commit 0d5501c1c828fb97d02af50aa9d2b1a5498b94e4 ] Currently the functionality to untag traffic on input resides as part of the vlan module and is build only when VLAN support is enabled in the kernel. When VLAN is disabled, the function vlan_untag() turns into a stub and doesn't really untag the packets. This seems to create an interesting interaction between VMs supporting checksum offloading and some network drivers. There are some drivers that do not allow the user to change tx-vlan-offload feature of the driver. These drivers also seem to assume that any VLAN-tagged traffic they transmit will have the vlan information in the vlan_tci and not in the vlan header already in the skb. When transmitting skbs that already have tagged data with partial checksum set, the checksum doesn't appear to be updated correctly by the card thus resulting in a failure to establish TCP connections. The following is a packet trace taken on the receiver where a sender is a VM with a VLAN configued. The host VM is running on doest not have VLAN support and the outging interface on the host is tg3: 10:12:43.503055 52:54:00:ae:42:3f > 28:d2:44:7d:c2:de, ethertype 802.1Q (0x8100), length 78: vlan 100, p 0, ethertype IPv4, (tos 0x0, ttl 64, id 27243, offset 0, flags [DF], proto TCP (6), length 60) 10.0.100.1.58545 > 10.0.100.10.ircu-2: Flags [S], cksum 0xdc39 (incorrect -> 0x48d9), seq 1069378582, win 29200, options [mss 1460,sackOK,TS val 4294837885 ecr 0,nop,wscale 7], length 0 10:12:44.505556 52:54:00:ae:42:3f > 28:d2:44:7d:c2:de, ethertype 802.1Q (0x8100), length 78: vlan 100, p 0, ethertype IPv4, (tos 0x0, ttl 64, id 27244, offset 0, flags [DF], proto TCP (6), length 60) 10.0.100.1.58545 > 10.0.100.10.ircu-2: Flags [S], cksum 0xdc39 (incorrect -> 0x44ee), seq 1069378582, win 29200, options [mss 1460,sackOK,TS val 4294838888 ecr 0,nop,wscale 7], length 0 This connection finally times out. I've only access to the TG3 hardware in this configuration thus have only tested this with TG3 driver. There are a lot of other drivers that do not permit user changes to vlan acceleration features, and I don't know if they all suffere from a similar issue. The patch attempt to fix this another way. It moves the vlan header stipping code out of the vlan module and always builds it into the kernel network core. This way, even if vlan is not supported on a virtualizatoin host, the virtual machines running on top of such host will still work with VLANs enabled. CC: Patrick McHardy <kaber@trash.net> CC: Nithin Nayak Sujir <nsujir@broadcom.com> CC: Michael Chan <mchan@broadcom.com> CC: Jiri Pirko <jiri@resnulli.us> Signed-off-by: Vladislav Yasevich <vyasevic@redhat.com> Acked-by: Jiri Pirko <jiri@resnulli.us> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2014-10-13jiffies: Fix timeval conversion to jiffiesAndrew Hunter
commit d78c9300c51d6ceed9f6d078d4e9366f259de28c upstream. timeval_to_jiffies tried to round a timeval up to an integral number of jiffies, but the logic for doing so was incorrect: intervals corresponding to exactly N jiffies would become N+1. This manifested itself particularly repeatedly stopping/starting an itimer: setitimer(ITIMER_PROF, &val, NULL); setitimer(ITIMER_PROF, NULL, &val); would add a full tick to val, _even if it was exactly representable in terms of jiffies_ (say, the result of a previous rounding.) Doing this repeatedly would cause unbounded growth in val. So fix the math. Here's what was wrong with the conversion: we essentially computed (eliding seconds) jiffies = usec * (NSEC_PER_USEC/TICK_NSEC) by using scaling arithmetic, which took the best approximation of NSEC_PER_USEC/TICK_NSEC with denominator of 2^USEC_JIFFIE_SC = x/(2^USEC_JIFFIE_SC), and computed: jiffies = (usec * x) >> USEC_JIFFIE_SC and rounded this calculation up in the intermediate form (since we can't necessarily exactly represent TICK_NSEC in usec.) But the scaling arithmetic is a (very slight) *over*approximation of the true value; that is, instead of dividing by (1 usec/ 1 jiffie), we effectively divided by (1 usec/1 jiffie)-epsilon (rounding down). This would normally be fine, but we want to round timeouts up, and we did so by adding 2^USEC_JIFFIE_SC - 1 before the shift; this would be fine if our division was exact, but dividing this by the slightly smaller factor was equivalent to adding just _over_ 1 to the final result (instead of just _under_ 1, as desired.) In particular, with HZ=1000, we consistently computed that 10000 usec was 11 jiffies; the same was true for any exact multiple of TICK_NSEC. We could possibly still round in the intermediate form, adding something less than 2^USEC_JIFFIE_SC - 1, but easier still is to convert usec->nsec, round in nanoseconds, and then convert using time*spec*_to_jiffies. This adds one constant multiplication, and is not observably slower in microbenchmarks on recent x86 hardware. Tested: the following program: int main() { struct itimerval zero = {{0, 0}, {0, 0}}; /* Initially set to 10 ms. */ struct itimerval initial = zero; initial.it_interval.tv_usec = 10000; setitimer(ITIMER_PROF, &initial, NULL); /* Save and restore several times. */ for (size_t i = 0; i < 10; ++i) { struct itimerval prev; setitimer(ITIMER_PROF, &zero, &prev); /* on old kernels, this goes up by TICK_USEC every iteration */ printf("previous value: %ld %ld %ld %ld\n", prev.it_interval.tv_sec, prev.it_interval.tv_usec, prev.it_value.tv_sec, prev.it_value.tv_usec); setitimer(ITIMER_PROF, &prev, NULL); } return 0; } Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Paul Turner <pjt@google.com> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Prarit Bhargava <prarit@redhat.com> Reviewed-by: Paul Turner <pjt@google.com> Reported-by: Aaron Jacobs <jacobsa@google.com> Signed-off-by: Andrew Hunter <ahh@google.com> [jstultz: Tweaked to apply to 3.17-rc] Signed-off-by: John Stultz <john.stultz@linaro.org> [bwh: Backported to 3.16: adjust filename] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2014-10-13vgaswitcheroo: add vga_switcheroo_fini_domain_pm_opsAlex Deucher
commit 766a53d059d1500c9755c8af017bd411bd8f1b20 upstream. Drivers should call this on unload to unregister pmops. Bug: https://bugzilla.kernel.org/show_bug.cgi?id=84431 Reviewed-by: Ben Skeggs <bskeggs@redhat.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Pali Rohár <pali.rohar@gmail.com> Cc: Ben Skeggs <bskeggs@redhat.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2014-10-13workqueue: apply __WQ_ORDERED to create_singlethread_workqueue()Tejun Heo
commit e09c2c295468476a239d13324ce9042ec4de05eb upstream. create_singlethread_workqueue() is a compat interface for single threaded workqueue which maps to ordered workqueue w/ rescuer in the current implementation. create_singlethread_workqueue() currently implemented by invoking alloc_workqueue() w/ appropriate parameters. 8719dceae2f9 ("workqueue: reject adjusting max_active or applying attrs to ordered workqueues") introduced __WQ_ORDERED to protect ordered workqueues against dynamic attribute changes which can break ordering guarantees but forgot to apply it to create_singlethread_workqueue(). This in itself is okay as nobody currently uses dynamic attribute change on workqueues created with create_singlethread_workqueue(). However, 4c16bd327c ("workqueue: implement NUMA affinity for unbound workqueues") broke singlethreaded guarantee for ordered workqueues through allocating a separate pool_workqueue on each NUMA node by default. A later change 8a2b75384444 ("workqueue: fix ordered workqueues in NUMA setups") fixed it by allocating only one global pool_workqueue if __WQ_ORDERED is set. Combined, the __WQ_ORDERED omission in create_singlethread_workqueue() became critical breaking its single threadedness and ordering guarantee. Let's make create_singlethread_workqueue() wrap alloc_ordered_workqueue() instead so that it inherits __WQ_ORDERED and can implicitly track future ordered_workqueue changes. v2: I missed that __WQ_ORDERED now protects against pwq splitting across NUMA nodes and incorrectly described the patch as a nice-to-have fix to protect against future dynamic attribute usages. Oleg pointed out that this is actually a critical breakage due to 8a2b75384444 ("workqueue: fix ordered workqueues in NUMA setups"). Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Mike Anderson <mike.anderson@us.ibm.com> Cc: Oleg Nesterov <onestero@redhat.com> Cc: Gustavo Luiz Duarte <gduarte@redhat.com> Cc: Tomas Henzl <thenzl@redhat.com> Fixes: 4c16bd327c ("workqueue: implement NUMA affinity for unbound workqueues") Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2014-10-13iio:trigger: modify return value for iio_trigger_getSrinivas Pandruvada
commit f153566570fb9e32c2f59182883f4f66048788fb upstream. Instead of a void function, return the trigger pointer. Whilst not in of itself a fix, this makes the following set of 7 fixes cleaner than they would otherwise be. Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2014-10-13iio: hid_Sensors: fix crash during trigger unregisterSrinivas Pandruvada
commit ec7f68e07bf10198717b7824c78201b46bbf1956 upstream. We can't store the trigger instance created by iio_trigger_alloc, in trig field of iio_device structure. This needs to be stored in the driver private data. Othewise it can result in crash during module unload. Hence created a trig_ptr in the common data structure for each HID sensor IIO driver and storing here. Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2014-09-26mm: page_alloc: reduce cost of the fair zone allocation policyMel Gorman
commit 4ffeaf3560a52b4a69cc7909873d08c0ef5909d4 upstream. The fair zone allocation policy round-robins allocations between zones within a node to avoid age inversion problems during reclaim. If the first allocation fails, the batch counts are reset and a second attempt made before entering the slow path. One assumption made with this scheme is that batches expire at roughly the same time and the resets each time are justified. This assumption does not hold when zones reach their low watermark as the batches will be consumed at uneven rates. Allocation failure due to watermark depletion result in additional zonelist scans for the reset and another watermark check before hitting the slowpath. On UMA, the benefit is negligible -- around 0.25%. On 4-socket NUMA machine it's variable due to the variability of measuring overhead with the vmstat changes. The system CPU overhead comparison looks like 3.16.0-rc3 3.16.0-rc3 3.16.0-rc3 vanilla vmstat-v5 lowercost-v5 User 746.94 774.56 802.00 System 65336.22 32847.27 40852.33 Elapsed 27553.52 27415.04 27368.46 However it is worth noting that the overall benchmark still completed faster and intuitively it makes sense to take as few passes as possible through the zonelists. Signed-off-by: Mel Gorman <mgorman@suse.de> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Mel Gorman <mgorman@suse.de> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2014-09-26mm: move zone->pages_scanned into a vmstat counterMel Gorman
commit 0d5d823ab4e608ec7b52ac4410de4cb74bbe0edd upstream. zone->pages_scanned is a write-intensive cache line during page reclaim and it's also updated during page free. Move the counter into vmstat to take advantage of the per-cpu updates and do not update it in the free paths unless necessary. On a small UMA machine running tiobench the difference is marginal. On a 4-node machine the overhead is more noticable. Note that automatic NUMA balancing was disabled for this test as otherwise the system CPU overhead is unpredictable. 3.16.0-rc3 3.16.0-rc3 3.16.0-rc3 vanillarearrange-v5 vmstat-v5 User 746.94 759.78 774.56 System 65336.22 58350.98 32847.27 Elapsed 27553.52 27282.02 27415.04 Note that the overhead reduction will vary depending on where exactly pages are allocated and freed. Signed-off-by: Mel Gorman <mgorman@suse.de> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Mel Gorman <mgorman@suse.de> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2014-09-26mm: rearrange zone fields into read-only, page alloc, statistics and page ↵Mel Gorman
reclaim lines commit 3484b2de9499df23c4604a513b36f96326ae81ad upstream. The arrangement of struct zone has changed over time and now it has reached the point where there is some inappropriate sharing going on. On x86-64 for example o The zone->node field is shared with the zone lock and zone->node is accessed frequently from the page allocator due to the fair zone allocation policy. o span_seqlock is almost never used by shares a line with free_area o Some zone statistics share a cache line with the LRU lock so reclaim-intensive and allocator-intensive workloads can bounce the cache line on a stat update This patch rearranges struct zone to put read-only and read-mostly fields together and then splits the page allocator intensive fields, the zone statistics and the page reclaim intensive fields into their own cache lines. Note that the type of lowmem_reserve changes due to the watermark calculations being signed and avoiding a signed/unsigned conversion there. On the test configuration I used the overall size of struct zone shrunk by one cache line. On smaller machines, this is not likely to be noticable. However, on a 4-node NUMA machine running tiobench the system CPU overhead is reduced by this patch. 3.16.0-rc3 3.16.0-rc3 vanillarearrange-v5r9 User 746.94 759.78 System 65336.22 58350.98 Elapsed 27553.52 27282.02 Signed-off-by: Mel Gorman <mgorman@suse.de> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Mel Gorman <mgorman@suse.de> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2014-09-26mm: make copy_pte_range static againJerome Marchand
commit 21bda264f4243f61dfcc485174055f12ad0530b4 upstream. Commit 71e3aac0724f ("thp: transparent hugepage core") adds copy_pte_range prototype to huge_mm.h. I'm not sure why (or if) this function have been used outside of memory.c, but it currently isn't. This patch makes copy_pte_range() static again. Signed-off-by: Jerome Marchand <jmarchan@redhat.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Mel Gorman <mgorman@suse.de> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2014-09-26mm: non-atomically mark page accessed during page cache allocation where ↵Mel Gorman
possible commit 2457aec63745e235bcafb7ef312b182d8682f0fc upstream. aops->write_begin may allocate a new page and make it visible only to have mark_page_accessed called almost immediately after. Once the page is visible the atomic operations are necessary which is noticable overhead when writing to an in-memory filesystem like tmpfs but should also be noticable with fast storage. The objective of the patch is to initialse the accessed information with non-atomic operations before the page is visible. The bulk of filesystems directly or indirectly use grab_cache_page_write_begin or find_or_create_page for the initial allocation of a page cache page. This patch adds an init_page_accessed() helper which behaves like the first call to mark_page_accessed() but may called before the page is visible and can be done non-atomically. The primary APIs of concern in this care are the following and are used by most filesystems. find_get_page find_lock_page find_or_create_page grab_cache_page_nowait grab_cache_page_write_begin All of them are very similar in detail to the patch creates a core helper pagecache_get_page() which takes a flags parameter that affects its behavior such as whether the page should be marked accessed or not. Then old API is preserved but is basically a thin wrapper around this core function. Each of the filesystems are then updated to avoid calling mark_page_accessed when it is known that the VM interfaces have already done the job. There is a slight snag in that the timing of the mark_page_accessed() has now changed so in rare cases it's possible a page gets to the end of the LRU as PageReferenced where as previously it might have been repromoted. This is expected to be rare but it's worth the filesystem people thinking about it in case they see a problem with the timing change. It is also the case that some filesystems may be marking pages accessed that previously did not but it makes sense that filesystems have consistent behaviour in this regard. The test case used to evaulate this is a simple dd of a large file done multiple times with the file deleted on each iterations. The size of the file is 1/10th physical memory to avoid dirty page balancing. In the async case it will be possible that the workload completes without even hitting the disk and will have variable results but highlight the impact of mark_page_accessed for async IO. The sync results are expected to be more stable. The exception is tmpfs where the normal case is for the "IO" to not hit the disk. The test machine was single socket and UMA to avoid any scheduling or NUMA artifacts. Throughput and wall times are presented for sync IO, only wall times are shown for async as the granularity reported by dd and the variability is unsuitable for comparison. As async results were variable do to writback timings, I'm only reporting the maximum figures. The sync results were stable enough to make the mean and stddev uninteresting. The performance results are reported based on a run with no profiling. Profile data is based on a separate run with oprofile running. async dd 3.15.0-rc3 3.15.0-rc3 vanilla accessed-v2 ext3 Max elapsed 13.9900 ( 0.00%) 11.5900 ( 17.16%) tmpfs Max elapsed 0.5100 ( 0.00%) 0.4900 ( 3.92%) btrfs Max elapsed 12.8100 ( 0.00%) 12.7800 ( 0.23%) ext4 Max elapsed 18.6000 ( 0.00%) 13.3400 ( 28.28%) xfs Max elapsed 12.5600 ( 0.00%) 2.0900 ( 83.36%) The XFS figure is a bit strange as it managed to avoid a worst case by sheer luck but the average figures looked reasonable. samples percentage ext3 86107 0.9783 vmlinux-3.15.0-rc4-vanilla mark_page_accessed ext3 23833 0.2710 vmlinux-3.15.0-rc4-accessed-v3r25 mark_page_accessed ext3 5036 0.0573 vmlinux-3.15.0-rc4-accessed-v3r25 init_page_accessed ext4 64566 0.8961 vmlinux-3.15.0-rc4-vanilla mark_page_accessed ext4 5322 0.0713 vmlinux-3.15.0-rc4-accessed-v3r25 mark_page_accessed ext4 2869 0.0384 vmlinux-3.15.0-rc4-accessed-v3r25 init_page_accessed xfs 62126 1.7675 vmlinux-3.15.0-rc4-vanilla mark_page_accessed xfs 1904 0.0554 vmlinux-3.15.0-rc4-accessed-v3r25 init_page_accessed xfs 103 0.0030 vmlinux-3.15.0-rc4-accessed-v3r25 mark_page_accessed btrfs 10655 0.1338 vmlinux-3.15.0-rc4-vanilla mark_page_accessed btrfs 2020 0.0273 vmlinux-3.15.0-rc4-accessed-v3r25 init_page_accessed btrfs 587 0.0079 vmlinux-3.15.0-rc4-accessed-v3r25 mark_page_accessed tmpfs 59562 3.2628 vmlinux-3.15.0-rc4-vanilla mark_page_accessed tmpfs 1210 0.0696 vmlinux-3.15.0-rc4-accessed-v3r25 init_page_accessed tmpfs 94 0.0054 vmlinux-3.15.0-rc4-accessed-v3r25 mark_page_accessed [akpm@linux-foundation.org: don't run init_page_accessed() against an uninitialised pointer] Signed-off-by: Mel Gorman <mgorman@suse.de> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Jan Kara <jack@suse.cz> Cc: Michal Hocko <mhocko@suse.cz> Cc: Hugh Dickins <hughd@google.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Theodore Ts'o <tytso@mit.edu> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Rik van Riel <riel@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Tested-by: Prabhakar Lad <prabhakar.csengg@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Mel Gorman <mgorman@suse.de> Signed-off-by: Jiri Slaby <jslaby@suse.cz>