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2018-10-01iommu/dma: Add support for non-strict modeZhen Lei2-1/+32
With the flush queue infrastructure already abstracted into IOVA domains, hooking it up in iommu-dma is pretty simple. Since there is a degree of dependency on the IOMMU driver knowing what to do to play along, we key the whole thing off a domain attribute which will be set on default DMA ops domains to request non-strict invalidation. That way, drivers can indicate the appropriate support by acknowledging the attribute, and we can easily fall back to strict invalidation otherwise. The flush queue callback needs a handle on the iommu_domain which owns our cookie, so we have to add a pointer back to that, but neatly, that's also sufficient to indicate whether we're using a flush queue or not, and thus which way to release IOVAs. The only slight subtlety is switching __iommu_dma_unmap() from calling iommu_unmap() to explicit iommu_unmap_fast()/iommu_tlb_sync() so that we can elide the sync entirely in non-strict mode. Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com> [rm: convert to domain attribute, tweak comments and commit message] Signed-off-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-10-01iommu/arm-smmu: Ensure that page-table updates are visible before TLBIWill Deacon1-0/+6
The IO-pgtable code relies on the driver TLB invalidation callbacks to ensure that all page-table updates are visible to the IOMMU page-table walker. In the case that the page-table walker is cache-coherent, we cannot rely on an implicit DSB from the DMA-mapping code, so we must ensure that we execute a DSB in our tlb_add_flush() callback prior to triggering the invalidation. Cc: <stable@vger.kernel.org> Cc: Robin Murphy <robin.murphy@arm.com> Fixes: 2df7a25ce4a7 ("iommu/arm-smmu: Clean up DMA API usage") Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-10-01iommu/arm-smmu-v3: Implement flush_iotlb_all hookZhen Lei1-1/+9
.flush_iotlb_all is currently stubbed to arm_smmu_iotlb_sync() since the only time it would ever need to actually do anything is for callers doing their own explicit batching, e.g.: iommu_unmap_fast(domain, ...); iommu_unmap_fast(domain, ...); iommu_iotlb_flush_all(domain, ...); where since io-pgtable still issues the TLBI commands implicitly in the unmap instead of implementing .iotlb_range_add, the "flush" only needs to ensure completion of those already-in-flight invalidations. However, we're about to start using it in anger with flush queues, so let's get a proper implementation wired up. Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com> Reviewed-by: Robin Murphy <robin.murphy@arm.com> [rm: document why it wasn't a bug] Signed-off-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-10-01iommu/arm-smmu-v3: Avoid back-to-back CMD_SYNC operationsZhen Lei1-3/+13
Putting adjacent CMD_SYNCs into the command queue is nonsensical, but can happen when multiple CPUs are inserting commands. Rather than leave the poor old hardware to chew through these operations, we can instead drop the subsequent SYNCs and poll for completion of the first. This has been shown to improve IO performance under pressure, where the number of SYNC operations reduces by about a third: CMD_SYNCs reduced: 19542181 CMD_SYNCs total: 58098548 (include reduced) CMDs total: 116197099 (TLBI:SYNC about 1:1) Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-10-01iommu/arm-smmu-v3: Fix unexpected CMD_SYNC timeoutZhen Lei1-5/+3
The condition break condition of: (int)(VAL - sync_idx) >= 0 in the __arm_smmu_sync_poll_msi() polling loop requires that sync_idx must be increased monotonically according to the sequence of the CMDs in the cmdq. However, since the msidata is populated using atomic_inc_return_relaxed() before taking the command-queue spinlock, then the following scenario can occur: CPU0 CPU1 msidata=0 msidata=1 insert cmd1 insert cmd0 smmu execute cmd1 smmu execute cmd0 poll timeout, because msidata=1 is overridden by cmd0, that means VAL=0, sync_idx=1. This is not a functional problem, since the caller will eventually either timeout or exit due to another CMD_SYNC, however it's clearly not what the code is supposed to be doing. Fix it, by incrementing the sequence count with the command-queue lock held, allowing us to drop the atomic operations altogether. Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com> [will: dropped the specialised cmd building routine for now] Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-10-01iommu/io-pgtable-arm: Fix race handling in split_blk_unmap()Robin Murphy1-5/+4
In removing the pagetable-wide lock, we gained the possibility of the vanishingly unlikely case where we have a race between two concurrent unmappers splitting the same block entry. The logic to handle this is fairly straightforward - whoever loses the race frees their partial next-level table and instead dereferences the winner's newly-installed entry in order to fall back to a regular unmap, which intentionally echoes the pre-existing case of recursively splitting a 1GB block down to 4KB pages by installing a full table of 2MB blocks first. Unfortunately, the chump who implemented that logic failed to update the condition check for that fallback, meaning that if said race occurs at the last level (where the loser's unmap_idx is valid) then the unmap won't actually happen. Fix that to properly account for both the race and recursive cases. Fixes: 2c3d273eabe8 ("iommu/io-pgtable-arm: Support lockless operation") Signed-off-by: Robin Murphy <robin.murphy@arm.com> [will: re-jig control flow to avoid duplicate cmpxchg test] Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-10-01iommu/arm-smmu-v3: Fix a couple of minor comment typosJohn Garry1-3/+3
Fix some comment typos spotted. Signed-off-by: John Garry <john.garry@huawei.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-08-26Linux 4.19-rc1v4.19-rc1Linus Torvalds1-2/+2
2018-08-25mm/cow: don't bother write protecting already write-protected pagesLinus Torvalds1-1/+1
This is not normally noticeable, but repeated forks are unnecessarily expensive because they repeatedly dirty the parent page tables during the page table copy operation. It's trivial to just avoid write protecting the page table entry if it was already not writable. This patch was inspired by https://bugzilla.kernel.org/show_bug.cgi?id=200447 which points to an ancient "waste time re-doing fork" issue in the presence of lots of signals. That bug was fixed by Eric Biederman's signal handling series culminating in commit c3ad2c3b02e9 ("signal: Don't restart fork when signals come in"), but the unnecessary work for repeated forks is still work just fixing, particularly since the fix is trivial. Cc: Eric Biederman <ebiederm@xmission.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-25hpfs: remove unnecessary checks on the value of r when assigning error codeColin Ian King1-1/+1
At the point where r is being checked for different values, r is always going to be equal to 2 as the previous if statements jump to end or end1 if r is not 2. Hence the assignment to err can be simplified to just err an assignment without any checks on the value or r. Detected by CoverityScan, CID#1226737 ("Logically dead code") Signed-off-by: Colin Ian King <colin.king@canonical.com> Reviewed-by: Mikulas Patocka <mikulas@artax.karlin.mff.cuni.cz> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-25libata: maintainership updateJens Axboe1-3/+3
Tejun Heo wrote: > > I asked Jens whether he could take care of the libata tree and he > thankfully agreed, so, from now on, Jens will be the libata > maintainer. > > Thanks a lot! Thanks for your work in this area. I still remember the first linux storage summit we did in Vancouver 2001, Tejun was invited to talk about his libata error handling work. Before that, it was basically a crap shoot if we recovered properly or not... A lot of water has flown under the bridge since then! Here's an "official" patch. Linus, can you apply it? Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-24iommu/rockchip: Move irq request past pm_runtime_enableMarc Zyngier1-11/+13
Enabling the interrupt early, before power has been applied to the device, can result in an interrupt being delivered too early if: - the IOMMU shares an interrupt with a VOP - the VOP has a pending interrupt (after a kexec, for example) In these conditions, we end-up taking the interrupt without the IOMMU being ready to handle the interrupt (not powered on). Moving the interrupt request past the pm_runtime_enable() call makes sure we can at least access the IOMMU registers. Note that this is only a partial fix, and that the VOP interrupt will still be screaming until the VOP driver kicks in, which advocates for a more synchronized interrupt enabling/disabling approach. Fixes: 0f181d3cf7d98 ("iommu/rockchip: Add runtime PM support") Reviewed-by: Heiko Stuebner <heiko@sntech.de> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Olof Johansson <olof@lixom.net>
2018-08-24iommu/rockchip: Handle errors returned from PM frameworkMarc Zyngier1-6/+15
pm_runtime_get_if_in_use can fail: either PM has been disabled altogether (-EINVAL), or the device hasn't been enabled yet (0). Sadly, the Rockchip IOMMU driver tends to conflate the two things by considering a non-zero return value as successful. This has the consequence of hiding other bugs, so let's handle this case throughout the driver, with a WARN_ON_ONCE so that we can try and work out what happened. Fixes: 0f181d3cf7d98 ("iommu/rockchip: Add runtime PM support") Reviewed-by: Heiko Stuebner <heiko@sntech.de> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Olof Johansson <olof@lixom.net>
2018-08-24arm64: rockchip: Force CONFIG_PM on Rockchip systemsMarc Zyngier1-0/+1
A number of the Rockchip-specific drivers (IOMMU, display controllers) are now assuming that CONFIG_PM is set, and may completely misbehave if that's not the case. Since there is hardly any reason for this configuration option not to be selected anyway, let's require it (in the same way Tegra already does). Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Olof Johansson <olof@lixom.net>
2018-08-24ARM: rockchip: Force CONFIG_PM on Rockchip systemsMarc Zyngier1-0/+1
A number of the Rockchip-specific drivers (IOMMU, display controllers) are now assuming that CONFIG_PM is set, and may completely misbehave if that's not the case. Since there is hardly any reason for this configuration option not to be selected anyway, let's require it (in the same way Tegra already does). Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Olof Johansson <olof@lixom.net>
2018-08-24arm64: dts: Fix various entry-method properties to reflect documentationAmit Kucheria11-12/+12
The idle-states binding documentation[1] mentions that the 'entry-method' property is required on 64-bit platforms and must be set to "psci". commit a13f18f59d26 ("Documentation: arm: Fix typo in the idle-states bindings examples") attempted to fix this earlier but clearly more is needed. Fix the cpu-capacity.txt documentation that uses the incorrect value so we don't get copy-paste errors like these. Clarify the language in idle-states.txt by removing the reference to the psci bindings that might be causing this confusion. Finally, fix devicetrees of various boards to reflect current documentation. [1] Documentation/devicetree/bindings/arm/idle-states.txt (see idle-states node) Signed-off-by: Amit Kucheria <amit.kucheria@linaro.org> Acked-by: Sudeep Holla <sudeep.holla@arm.com> Acked-by: Li Yang <leoyang.li@nxp.com> Signed-off-by: Olof Johansson <olof@lixom.net>
2018-08-24i2c: don't use any __deprecated handling anymoreSedat Dilek1-1/+0
This can be dropped with commit 771c035372a036f83353eef46dbb829780330234 ("deprecate the '__deprecated' attribute warnings entirely and for good") now in upstream. And we got rid of the last __deprecated use, too. Signed-off-by: Sedat Dilek <sedat.dilek@credativ.de> [wsa: shortened commit message to reflect the current situation] Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-08-24x86/speculation/l1tf: Suggest what to do on systems with too much RAMVlastimil Babka1-0/+4
Two users have reported [1] that they have an "extremely unlikely" system with more than MAX_PA/2 memory and L1TF mitigation is not effective. Make the warning more helpful by suggesting the proper mem=X kernel boot parameter to make it effective and a link to the L1TF document to help decide if the mitigation is worth the unusable RAM. [1] https://bugzilla.suse.com/show_bug.cgi?id=1105536 Suggested-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Cc: "H . Peter Anvin" <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andi Kleen <ak@linux.intel.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/966571f0-9d7f-43dc-92c6-a10eec7a1254@suse.cz
2018-08-24i2c: use SPDX identifier for Renesas driversWolfram Sang5-30/+5
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Simon Horman <horms+renesas@verge.net.au> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-08-24i2c: ocores: update my email addressPeter Korsgaard4-5/+5
The old @sunsite.dk address is no longer active, so update the references. Signed-off-by: Peter Korsgaard <peter@korsgaard.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-08-24i2c: remove deprecated attach_adapter callbackWolfram Sang2-16/+1
There aren't any users left. Remove this callback from the 2.4 times. Phew, finally, that took years to reach... Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-08-24macintosh: therm_windtunnel: drop using attach_adapterWolfram Sang1-2/+23
As we now have deferred probing, we can use a custom mechanism and finally get rid of the legacy interface from the i2c core. Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Acked-by: Michael Ellerman <mpe@ellerman.id.au>
2018-08-24ubifs: Remove empty file.hRichard Weinberger1-0/+0
This empty file sneaked into the tree by mistake. Remove it. Fixes: 6eb61d587f45 ("ubifs: Pass struct ubifs_info to ubifs_assert()") Signed-off-by: Richard Weinberger <richard@nod.at>
2018-08-24x86/speculation/l1tf: Fix off-by-one error when warning that system has too ↵Vlastimil Babka3-3/+3
much RAM Two users have reported [1] that they have an "extremely unlikely" system with more than MAX_PA/2 memory and L1TF mitigation is not effective. In fact it's a CPU with 36bits phys limit (64GB) and 32GB memory, but due to holes in the e820 map, the main region is almost 500MB over the 32GB limit: [ 0.000000] BIOS-e820: [mem 0x0000000100000000-0x000000081effffff] usable Suggestions to use 'mem=32G' to enable the L1TF mitigation while losing the 500MB revealed, that there's an off-by-one error in the check in l1tf_select_mitigation(). l1tf_pfn_limit() returns the last usable pfn (inclusive) and the range check in the mitigation path does not take this into account. Instead of amending the range check, make l1tf_pfn_limit() return the first PFN which is over the limit which is less error prone. Adjust the other users accordingly. [1] https://bugzilla.suse.com/show_bug.cgi?id=1105536 Fixes: 17dbca119312 ("x86/speculation/l1tf: Add sysfs reporting for l1tf") Reported-by: George Anchev <studio@anchev.net> Reported-by: Christopher Snowhill <kode54@gmail.com> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: "H . Peter Anvin" <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andi Kleen <ak@linux.intel.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180823134418.17008-1-vbabka@suse.cz
2018-08-24mm: Change return type int to vm_fault_t for fault handlersSouptick Joarder15-103/+106
Use new return type vm_fault_t for fault handler. For now, this is just documenting that the function returns a VM_FAULT value rather than an errno. Once all instances are converted, vm_fault_t will become a distinct type. Ref-> commit 1c8f422059ae ("mm: change return type to vm_fault_t") The aim is to change the return type of finish_fault() and handle_mm_fault() to vm_fault_t type. As part of that clean up return type of all other recursively called functions have been changed to vm_fault_t type. The places from where handle_mm_fault() is getting invoked will be change to vm_fault_t type but in a separate patch. vmf_error() is the newly introduce inline function in 4.17-rc6. [akpm@linux-foundation.org: don't shadow outer local `ret' in __do_huge_pmd_anonymous_page()] Link: http://lkml.kernel.org/r/20180604171727.GA20279@jordon-HP-15-Notebook-PC Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com> Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Matthew Wilcox <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-24lib/fonts: convert comments to utf-8Arnd Bergmann4-512/+512
The font files contain bit masks for characters in the cp437 character set, and comments showing what character this is supposed to be. This only makes sense when the terminal used to view the files is set to the same codepage, but all other files in the kernel now use utf-8 encoding. This changes those comments to utf-8 as well, for consistency. Link: http://lkml.kernel.org/r/20180724111600.4158975-3-arnd@arndb.de Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-24s390: ebcdic: convert comments to UTF-8Arnd Bergmann1-18/+18
The ebcdic.c file contains tables for converting between ebcdic and PC codepage 437. I could however not identify which encoding was used for the comments. This seems to be some variation of ISO_8859-1 with non-UTF-8 escape characters. I have converted this to UTF-8 by manually removing the escape characters and then running it through recode, to get the same encoding that we use for the rest of the kernel. Link: http://lkml.kernel.org/r/20180724111600.4158975-2-arnd@arndb.de Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-24treewide: convert ISO_8859-1 text comments to utf-8Arnd Bergmann12-103/+103
Almost all files in the kernel are either plain text or UTF-8 encoded. A couple however are ISO_8859-1, usually just a few characters in a C comments, for historic reasons. This converts them all to UTF-8 for consistency. Link: http://lkml.kernel.org/r/20180724111600.4158975-1-arnd@arndb.de Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Simon Horman <horms@verge.net.au> [IPVS portion] Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> [IIO] Acked-by: Michael Ellerman <mpe@ellerman.id.au> [powerpc] Acked-by: Rob Herring <robh@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Samuel Ortiz <sameo@linux.intel.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Rob Herring <robh+dt@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-24drivers/gpu/drm/gma500/: change return type to vm_fault_tSouptick Joarder3-27/+17
Use new return type vm_fault_t for fault handler. For now, this is just documenting that the function returns a VM_FAULT value rather than an errno. Once all instances are converted, vm_fault_t will become a distinct type. Ref-> 1c8f422059ae ("mm: change return type to vm_fault_t") Previously vm_insert_{pfn,mixed} returns err which driver mapped into VM_FAULT_* type. The new function vmf_insert_{pfn,mixed} will replace this inefficiency by returning VM_FAULT_* type. vmf_error() is the newly introduce inline function in 4.17-rc6. Link: http://lkml.kernel.org/r/20180713154541.GA3345@jordon-HP-15-Notebook-PC Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com> Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com> Cc: David Airlie <airlied@linux.ie> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Patrik Jakobsson <patrik.r.jakobsson@gmail.com> Cc: Matthew Wilcox <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-24docs/core-api: mm-api: add section about GFP flagsMike Rapoport1-0/+21
Link: http://lkml.kernel.org/r/1532626360-16650-8-git-send-email-rppt@linux.vnet.ibm.com Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Matthew Wilcox <willy@infradead.org> Cc: Michal Hocko <mhocko@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-24docs/mm: make GFP flags descriptions usable as kernel-docMike Rapoport1-137/+154
This patch adds DOC: headings for GFP flag descriptions and adjusts the formatting to fit sphinx expectations of paragraphs. Link: http://lkml.kernel.org/r/1532626360-16650-7-git-send-email-rppt@linux.vnet.ibm.com Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Matthew Wilcox <willy@infradead.org> Cc: Michal Hocko <mhocko@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-24docs/core-api: split memory management API to a separate fileMike Rapoport3-54/+58
This is basically copy-paste of the memory management section from kernel-api.rst with some minor adjustments: * The "User Space Memory Access" is moved to the beginning * The get_user_pages_fast reference is now a part of "User Space Memory Access" * And, of course, headings are adjusted with section being promoted to chapters Link: http://lkml.kernel.org/r/1532626360-16650-6-git-send-email-rppt@linux.vnet.ibm.com Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Matthew Wilcox <willy@infradead.org> Cc: Michal Hocko <mhocko@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-24docs/core-api: move *{str,mem}dup* to "String Manipulation"Mike Rapoport1-1/+5
The string and memory duplication routines fit better to the "String Manipulation" section than to "The SLAB Cache". Link: http://lkml.kernel.org/r/1532626360-16650-5-git-send-email-rppt@linux.vnet.ibm.com Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Matthew Wilcox <willy@infradead.org> Cc: Michal Hocko <mhocko@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-24docs/core-api: kill trailing whitespace in kernel-api.rstMike Rapoport1-1/+0
Link: http://lkml.kernel.org/r/1532626360-16650-4-git-send-email-rppt@linux.vnet.ibm.com Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Matthew Wilcox <willy@infradead.org> Cc: Michal Hocko <mhocko@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-24mm/util: add kernel-doc for kvfreeMike Rapoport1-0/+7
Link: http://lkml.kernel.org/r/1532626360-16650-3-git-send-email-rppt@linux.vnet.ibm.com Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Matthew Wilcox <willy@infradead.org> Cc: Michal Hocko <mhocko@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-24mm/util: make strndup_user description a kernel-doc commentMike Rapoport1-1/+1
Patch series "memory management documentation updates", v3. Here are several updates to the mm documentation. Aside from really minor changes in the first three patches, the updates are: * move the documentation of kstrdup and friends to "String Manipulation" section * split memory management API into a separate .rst file * adjust formating of the GFP flags description and include it in the reference documentation. This patch (of 7): The description of the strndup_user function misses '*' character at the beginning of the comment to be proper kernel-doc. Add the missing character. Link: http://lkml.kernel.org/r/1532626360-16650-2-git-send-email-rppt@linux.vnet.ibm.com Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Matthew Wilcox <willy@infradead.org> Cc: Michal Hocko <mhocko@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-24fs/proc/vmcore.c: hide vmcoredd_mmap_dumps() for nommu buildsArnd Bergmann1-0/+2
Without CONFIG_MMU, we get a build warning: fs/proc/vmcore.c:228:12: error: 'vmcoredd_mmap_dumps' defined but not used [-Werror=unused-function] static int vmcoredd_mmap_dumps(struct vm_area_struct *vma, unsigned long dst, The function is only referenced from an #ifdef'ed caller, so this uses the same #ifdef around it. Link: http://lkml.kernel.org/r/20180525213526.2117790-1-arnd@arndb.de Fixes: 7efe48df8a3d ("vmcore: append device dumps to vmcore as elf notes") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Ganesh Goudar <ganeshgr@chelsio.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Rahul Lakkireddy <rahul.lakkireddy@chelsio.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-24treewide: correct "differenciate" and "instanciate" typosFinn Thain8-8/+10
Also add these typos to spelling.txt so checkpatch.pl will look for them. Link: http://lkml.kernel.org/r/88af06b9de34d870cb0afc46cfd24e0458be2575.1529471371.git.fthain@telegraphics.com.au Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-24fs/afs: use new return type vm_fault_tSouptick Joarder2-2/+3
Use new return type vm_fault_t for fault handler in struct vm_operations_struct. For now, this is just documenting that the function returns a VM_FAULT value rather than an errno. Once all instances are converted, vm_fault_t will become a distinct type. See 1c8f422059ae ("mm: change return type to vm_fault_t") for reference. Link: http://lkml.kernel.org/r/20180702152017.GA3780@jordon-HP-15-Notebook-PC Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com> Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-24drivers/hwtracing/intel_th/msu.c: change return type to vm_fault_tSouptick Joarder1-1/+1
Use new return type vm_fault_t for fault handler. For now, this is just documenting that the function returns a VM_FAULT value rather than an errno. Once all instances are converted, vm_fault_t will become a distinct type. See 1c8f422059ae ("mm: change return type to vm_fault_t") for reference. Link: http://lkml.kernel.org/r/20180702155801.GA4010@jordon-HP-15-Notebook-PC Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-24mm: soft-offline: close the race against page allocationNaoya Horiguchi5-16/+57
A process can be killed with SIGBUS(BUS_MCEERR_AR) when it tries to allocate a page that was just freed on the way of soft-offline. This is undesirable because soft-offline (which is about corrected error) is less aggressive than hard-offline (which is about uncorrected error), and we can make soft-offline fail and keep using the page for good reason like "system is busy." Two main changes of this patch are: - setting migrate type of the target page to MIGRATE_ISOLATE. As done in free_unref_page_commit(), this makes kernel bypass pcplist when freeing the page. So we can assume that the page is in freelist just after put_page() returns, - setting PG_hwpoison on free page under zone->lock which protects freelists, so this allows us to avoid setting PG_hwpoison on a page that is decided to be allocated soon. [akpm@linux-foundation.org: tweak set_hwpoison_free_buddy_page() comment] Link: http://lkml.kernel.org/r/1531452366-11661-3-git-send-email-n-horiguchi@ah.jp.nec.com Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Reported-by: Xishi Qiu <xishi.qiuxishi@alibaba-inc.com> Tested-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: <zy.zhengyi@alibaba-inc.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-24mm: fix race on soft-offlining free huge pagesNaoya Horiguchi3-14/+21
Patch series "mm: soft-offline: fix race against page allocation". Xishi recently reported the issue about race on reusing the target pages of soft offlining. Discussion and analysis showed that we need make sure that setting PG_hwpoison should be done in the right place under zone->lock for soft offline. 1/2 handles free hugepage's case, and 2/2 hanldes free buddy page's case. This patch (of 2): There's a race condition between soft offline and hugetlb_fault which causes unexpected process killing and/or hugetlb allocation failure. The process killing is caused by the following flow: CPU 0 CPU 1 CPU 2 soft offline get_any_page // find the hugetlb is free mmap a hugetlb file page fault ... hugetlb_fault hugetlb_no_page alloc_huge_page // succeed soft_offline_free_page // set hwpoison flag mmap the hugetlb file page fault ... hugetlb_fault hugetlb_no_page find_lock_page return VM_FAULT_HWPOISON mm_fault_error do_sigbus // kill the process The hugetlb allocation failure comes from the following flow: CPU 0 CPU 1 mmap a hugetlb file // reserve all free page but don't fault-in soft offline get_any_page // find the hugetlb is free soft_offline_free_page // set hwpoison flag dissolve_free_huge_page // fail because all free hugepages are reserved page fault ... hugetlb_fault hugetlb_no_page alloc_huge_page ... dequeue_huge_page_node_exact // ignore hwpoisoned hugepage // and finally fail due to no-mem The root cause of this is that current soft-offline code is written based on an assumption that PageHWPoison flag should be set at first to avoid accessing the corrupted data. This makes sense for memory_failure() or hard offline, but does not for soft offline because soft offline is about corrected (not uncorrected) error and is safe from data lost. This patch changes soft offline semantics where it sets PageHWPoison flag only after containment of the error page completes successfully. Link: http://lkml.kernel.org/r/1531452366-11661-2-git-send-email-n-horiguchi@ah.jp.nec.com Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Reported-by: Xishi Qiu <xishi.qiuxishi@alibaba-inc.com> Suggested-by: Xishi Qiu <xishi.qiuxishi@alibaba-inc.com> Tested-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: <zy.zhengyi@alibaba-inc.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-24namei: allow restricted O_CREAT of FIFOs and regular filesSalvatore Mesoraca4-3/+106
Disallows open of FIFOs or regular files not owned by the user in world writable sticky directories, unless the owner is the same as that of the directory or the file is opened without the O_CREAT flag. The purpose is to make data spoofing attacks harder. This protection can be turned on and off separately for FIFOs and regular files via sysctl, just like the symlinks/hardlinks protection. This patch is based on Openwall's "HARDEN_FIFO" feature by Solar Designer. This is a brief list of old vulnerabilities that could have been prevented by this feature, some of them even allow for privilege escalation: CVE-2000-1134 CVE-2007-3852 CVE-2008-0525 CVE-2009-0416 CVE-2011-4834 CVE-2015-1838 CVE-2015-7442 CVE-2016-7489 This list is not meant to be complete. It's difficult to track down all vulnerabilities of this kind because they were often reported without any mention of this particular attack vector. In fact, before hardlinks/symlinks restrictions, fifos/regular files weren't the favorite vehicle to exploit them. [s.mesoraca16@gmail.com: fix bug reported by Dan Carpenter] Link: https://lkml.kernel.org/r/20180426081456.GA7060@mwanda Link: http://lkml.kernel.org/r/1524829819-11275-1-git-send-email-s.mesoraca16@gmail.com [keescook@chromium.org: drop pr_warn_ratelimited() in favor of audit changes in the future] [keescook@chromium.org: adjust commit subjet] Link: http://lkml.kernel.org/r/20180416175918.GA13494@beast Signed-off-by: Salvatore Mesoraca <s.mesoraca16@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org> Suggested-by: Solar Designer <solar@openwall.com> Suggested-by: Kees Cook <keescook@chromium.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-24hfs: prevent crash on exit from failed searchErnesto A. Fernández1-3/+4
hfs_find_exit() expects fd->bnode to be NULL after a search has failed. hfs_brec_insert() may instead set it to an error-valued pointer. Fix this to prevent a crash. Link: http://lkml.kernel.org/r/53d9749a029c41b4016c495fc5838c9dba3afc52.1530294815.git.ernesto.mnd.fernandez@gmail.com Signed-off-by: Ernesto A. Fernández <ernesto.mnd.fernandez@gmail.com> Cc: Anatoly Trosinenko <anatoly.trosinenko@gmail.com> Cc: Viacheslav Dubeyko <slava@dubeyko.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-24hfsplus: prevent crash on exit from failed searchErnesto A. Fernandez1-3/+4
hfs_find_exit() expects fd->bnode to be NULL after a search has failed. hfs_brec_insert() may instead set it to an error-valued pointer. Fix this to prevent a crash. Link: http://lkml.kernel.org/r/803590a35221fbf411b2c141419aea3233a6e990.1530294813.git.ernesto.mnd.fernandez@gmail.com Signed-off-by: Ernesto A. Fernandez <ernesto.mnd.fernandez@gmail.com> Reported-by: Anatoly Trosinenko <anatoly.trosinenko@gmail.com> Reviewed-by: Vyacheslav Dubeyko <slava@dubeyko.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-24hfsplus: fix NULL dereference in hfsplus_lookup()Ernesto A. Fernández1-2/+2
An HFS+ filesystem can be mounted read-only without having a metadata directory, which is needed to support hardlinks. But if the catalog data is corrupted, a directory lookup may still find dentries claiming to be hardlinks. hfsplus_lookup() does check that ->hidden_dir is not NULL in such a situation, but mistakenly does so after dereferencing it for the first time. Reorder this check to prevent a crash. This happens when looking up corrupted catalog data (dentry) on a filesystem with no metadata directory (this could only ever happen on a read-only mount). Wen Xu sent the replication steps in detail to the fsdevel list: https://bugzilla.kernel.org/show_bug.cgi?id=200297 Link: http://lkml.kernel.org/r/20180712215344.q44dyrhymm4ajkao@eaf Signed-off-by: Ernesto A. Fernández <ernesto.mnd.fernandez@gmail.com> Reported-by: Wen Xu <wen.xu@gatech.edu> Cc: Viacheslav Dubeyko <slava@dubeyko.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-24arm64: tlb: Provide forward declaration of tlb_flush() before including tlb.hWill Deacon1-0/+2
As of commit fd1102f0aade ("mm: mmu_notifier fix for tlb_end_vma"), asm-generic/tlb.h now calls tlb_flush() from a static inline function, so we need to make sure that it's declared before #including the asm-generic header in the arch header. Signed-off-by: Will Deacon <will.deacon@arm.com> Acked-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-24kbuild: rename LDFLAGS to KBUILD_LDFLAGSMasahiro Yamada29-51/+48
Commit a0f97e06a43c ("kbuild: enable 'make CFLAGS=...' to add additional options to CC") renamed CFLAGS to KBUILD_CFLAGS. Commit 222d394d30e7 ("kbuild: enable 'make AFLAGS=...' to add additional options to AS") renamed AFLAGS to KBUILD_AFLAGS. Commit 06c5040cdb13 ("kbuild: enable 'make CPPFLAGS=...' to add additional options to CPP") renamed CPPFLAGS to KBUILD_CPPFLAGS. For some reason, LDFLAGS was not renamed. Using a well-known variable like LDFLAGS may result in accidental override of the variable. Kbuild generally uses KBUILD_ prefixed variables for the internally appended options, so here is one more conversion to sanitize the naming convention. I did not touch Makefiles under tools/ since the tools build system is a different world. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reviewed-by: Palmer Dabbelt <palmer@sifive.com>
2018-08-24kbuild: pass LDFLAGS to recordmcount.plMasahiro Yamada1-1/+1
Since commit 0fbe9a245c60 ("microblaze: add endianness options to LDFLAGS instead of LD"), you cannot build the kernel for microblaze with CONFIG_DYNAMIC_FTRACE. Fixes: 0fbe9a245c60 ("microblaze: add endianness options to LDFLAGS instead of LD") Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-08-24kbuild: test dead code/data elimination support in KconfigMasahiro Yamada2-6/+4
This config option should be enabled only when both the compiler and the linker support necessary flags. Add proper dependencies to Kconfig. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>