- 07 2月, 2018 6 次提交
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由 Yury Norov 提交于
with bitmap_{from,to}_arr32 over the kernel. Additionally to it: * __check_eq_bitmap() now takes single nbits argument. * __check_eq_u32_array is not used in new test but may be used in future. So I don't remove it here, but annotate as __used. Tested on arm64 and 32-bit BE mips. [arnd@arndb.de: perf: arm_dsu_pmu: convert to bitmap_from_arr32] Link: http://lkml.kernel.org/r/20180201172508.5739-2-ynorov@caviumnetworks.com [ynorov@caviumnetworks.com: fix net/core/ethtool.c] Link: http://lkml.kernel.org/r/20180205071747.4ekxtsbgxkj5b2fz@yury-thinkpad Link: http://lkml.kernel.org/r/20171228150019.27953-2-ynorov@caviumnetworks.comSigned-off-by: NYury Norov <ynorov@caviumnetworks.com> Signed-off-by: NArnd Bergmann <arnd@arndb.de> Cc: Ben Hutchings <ben@decadent.org.uk> Cc: David Decotigny <decot@googlers.com>, Cc: David S. Miller <davem@davemloft.net>, Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Matthew Wilcox <mawilcox@microsoft.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Heiner Kallweit <hkallweit1@gmail.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Yury Norov 提交于
This patchset replaces bitmap_{to,from}_u32array with more simple and standard looking copy-like functions. bitmap_from_u32array() takes 4 arguments (bitmap_to_u32array is similar): - unsigned long *bitmap, which is destination; - unsigned int nbits, the length of destination bitmap, in bits; - const u32 *buf, the source; and - unsigned int nwords, the length of source buffer in ints. In description to the function it is detailed like: * copy min(nbits, 32*nwords) bits from @buf to @bitmap, remaining * bits between nword and nbits in @bitmap (if any) are cleared. Having two size arguments looks unneeded and potentially dangerous. It is unneeded because normally user of copy-like function should take care of the size of destination and make it big enough to fit source data. And it is dangerous because function may hide possible error if user doesn't provide big enough bitmap, and data becomes silently dropped. That's why all copy-like functions have 1 argument for size of copying data, and I don't see any reason to make bitmap_from_u32array() different. One exception that comes in mind is strncpy() which also provides size of destination in arguments, but it's strongly argued by the possibility of taking broken strings in source. This is not the case of bitmap_{from,to}_u32array(). There is no many real users of bitmap_{from,to}_u32array(), and they all very clearly provide size of destination matched with the size of source, so additional functionality is not used in fact. Like this: bitmap_from_u32array(to->link_modes.supported, __ETHTOOL_LINK_MODE_MASK_NBITS, link_usettings.link_modes.supported, __ETHTOOL_LINK_MODE_MASK_NU32); Where: #define __ETHTOOL_LINK_MODE_MASK_NU32 \ DIV_ROUND_UP(__ETHTOOL_LINK_MODE_MASK_NBITS, 32) In this patch, bitmap_copy_safe and bitmap_{from,to}_arr32 are introduced. 'Safe' in bitmap_copy_safe() stands for clearing unused bits in bitmap beyond last bit till the end of last word. It is useful for hardening API when bitmap is assumed to be exposed to userspace. bitmap_{from,to}_arr32 functions are replacements for bitmap_{from,to}_u32array. They don't take unneeded nwords argument, and so simpler in implementation and understanding. This patch suggests optimization for 32-bit systems - aliasing bitmap_{from,to}_arr32 to bitmap_copy_safe. Other possible optimization is aliasing 64-bit LE bitmap_{from,to}_arr32 to more generic function(s). But I didn't end up with the function that would be helpful by itself, and can be used to alias 64-bit LE bitmap_{from,to}_arr32, like bitmap_copy_safe() does. So I preferred to leave things as is. The following patch switches kernel to new API and introduces test for it. Discussion is here: https://lkml.org/lkml/2017/11/15/592 [ynorov@caviumnetworks.com: rename bitmap_copy_safe to bitmap_copy_clear_tail] Link: http://lkml.kernel.org/r/20180201172508.5739-3-ynorov@caviumnetworks.com Link: http://lkml.kernel.org/r/20171228150019.27953-1-ynorov@caviumnetworks.comSigned-off-by: NYury Norov <ynorov@caviumnetworks.com> Cc: Ben Hutchings <ben@decadent.org.uk> Cc: David Decotigny <decot@googlers.com>, Cc: David S. Miller <davem@davemloft.net>, Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Matthew Wilcox <mawilcox@microsoft.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Colin Ian King 提交于
Variable real_size is initialized with a value that is never read, it is re-assigned a new value later on, hence the initialization is redundant and can be removed. Cleans up clang warning: lib/test_kasan.c:422:21: warning: Value stored to 'real_size' during its initialization is never read Link: http://lkml.kernel.org/r/20180206144950.32457-1-colin.king@canonical.comSigned-off-by: NColin Ian King <colin.king@canonical.com> Acked-by: NAndrey Ryabinin <aryabinin@virtuozzo.com> Reviewed-by: NAndrew Morton <akpm@linux-foundation.org> Cc: Alexander Potapenko <glider@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Dmitry Vyukov 提交于
Detect frees of pointers into middle of heap objects. Link: http://lkml.kernel.org/r/cb569193190356beb018a03bb8d6fbae67e7adbc.1514378558.git.dvyukov@google.comSigned-off-by: NDmitry Vyukov <dvyukov@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>a Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Dmitry Vyukov 提交于
Patch series "kasan: detect invalid frees". KASAN detects double-frees, but does not detect invalid-frees (when a pointer into a middle of heap object is passed to free). We recently had a very unpleasant case in crypto code which freed an inner object inside of a heap allocation. This left unnoticed during free, but totally corrupted heap and later lead to a bunch of random crashes all over kernel code. Detect invalid frees. This patch (of 5): Detect frees of pointers into middle of large heap objects. I dropped const from kasan_kfree_large() because it starts propagating through a bunch of functions in kasan_report.c, slab/slub nearest_obj(), all of their local variables, fixup_red_left(), etc. Link: http://lkml.kernel.org/r/1b45b4fe1d20fc0de1329aab674c1dd973fee723.1514378558.git.dvyukov@google.comSigned-off-by: NDmitry Vyukov <dvyukov@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>a Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Paul Lawrence 提交于
Link: http://lkml.kernel.org/r/20171204191735.132544-5-paullawrence@google.comSigned-off-by: NGreg Hackmann <ghackmann@google.com> Signed-off-by: NPaul Lawrence <paullawrence@google.com> Acked-by: NAndrey Ryabinin <aryabinin@virtuozzo.com> Cc: Alexander Potapenko <glider@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Matthias Kaehlcke <mka@chromium.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 02 2月, 2018 1 次提交
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由 Andrey Ryabinin 提交于
strscpy() performs the word-at-a-time optimistic reads. So it may may access the memory past the end of the object, which is perfectly fine since strscpy() doesn't use that (past-the-end) data and makes sure the optimistic read won't cross a page boundary. Use new read_word_at_a_time() to shut up the KASAN. Note that this potentially could hide some bugs. In example bellow, stscpy() will copy more than we should (1-3 extra uninitialized bytes): char dst[8]; char *src; src = kmalloc(5, GFP_KERNEL); memset(src, 0xff, 5); strscpy(dst, src, 8); Signed-off-by: NAndrey Ryabinin <aryabinin@virtuozzo.com> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 27 1月, 2018 1 次提交
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由 Daniel Borkmann 提交于
Update selftests to relfect recent changes and add various new test cases. Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net> Acked-by: NAlexei Starovoitov <ast@kernel.org> Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
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- 24 1月, 2018 2 次提交
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由 Steven Rostedt (VMware) 提交于
When trace_printk() was introduced, it was discussed that making it be as low overhead as possible, that the processing of the format string should be delayed until it is read. That is, a "trace_printk()" should not convert the %d into numbers and so on, but instead, save the fmt string and all the args in the buffer at the time of recording. When the trace_printk() data is read, it would then parse the format string and do the conversions of the saved arguments in the tracing buffer. The code to perform this was added to vsprintf where vbin_printf() would save the arguments of a specified format string in a buffer, then bstr_printf() could be used to convert the buffer with the same format string into the final output, as if vsprintf() was called in one go. The issue arises when dereferenced pointers are used. The problem is that something like %*pbl which reads a bitmask, will save the pointer to the bitmask in the buffer. Then the reading of the buffer via bstr_printf() will then look at the pointer to process the final output. Obviously the value of that pointer could have changed since the time it was recorded to the time the buffer is read. Worse yet, the bitmask could be unmapped, and the reading of the trace buffer could actually cause a kernel oops. Another problem is that user space tools such as perf and trace-cmd do not have access to the contents of these pointers, and they become useless when the tracing buffer is extracted. Instead of having vbin_printf() simply save the pointer in the buffer for later processing, have it perform the formatting at the time bin_printf() is called. This will fix the issue of dereferencing pointers at a later time, and has the extra benefit of having user space tools understand these values. Since perf and trace-cmd already can handle %p[sSfF] via saving kallsyms, their pointers are saved and not processed during vbin_printf(). If they were converted, it would break perf and trace-cmd, as they would not know how to deal with the conversion. Link: http://lkml.kernel.org/r/20171228204025.14a71d8f@gandalf.local.homeReported-by: NThomas Gleixner <tglx@linutronix.de> Signed-off-by: NSteven Rostedt (VMware) <rostedt@goodmis.org>
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由 Bart Van Assche 提交于
Make it possible to call these two functions from a kernel module. Note: despite their name, these two functions can be used meaningfully independent of kobjects. A later patch will add calls to these functions from the SRP driver because this patch series modifies the SRP driver such that it can hold a reference to a namespace that can last longer than the lifetime of the process through which the namespace reference was obtained. Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com> Acked-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: NDoug Ledford <dledford@redhat.com>
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- 22 1月, 2018 2 次提交
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由 Wei Yongjun 提交于
Add the missing unlock before return from function config_num_requests_store() in the error handling case. Fixes: c92316bf ("test_firmware: add batched firmware tests") Cc: stable <stable@vger.kernel.org> Signed-off-by: NWei Yongjun <weiyongjun1@huawei.com> Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
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由 Wei Yongjun 提交于
Fixes the following sparse warnings: lib/test_firmware.c:99:20: warning: symbol 'test_fw_config' was not declared. Should it be static? Signed-off-by: NWei Yongjun <weiyongjun1@huawei.com> Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
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- 20 1月, 2018 2 次提交
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由 Daniel Borkmann 提交于
Add a couple of test cases for interpreter and JIT that are related to an issue we faced some time ago in Cilium [1], which is fixed in LLVM with commit e53750e1e086 ("bpf: fix bug on silently truncating 64-bit immediate"). Test cases were run-time checking kernel to behave as intended which should also provide some guidance for current or new JITs in case they should trip over this. Added for cBPF and eBPF. [1] https://github.com/cilium/cilium/pull/2162Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net> Acked-by: NAlexei Starovoitov <ast@kernel.org> Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
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由 Bart Van Assche 提交于
This patch avoids that workloads with large block sizes (megabytes) can trigger the following call stack with the ib_srpt driver (that driver is the only driver that chains scatterlists allocated by sgl_alloc_order()): BUG: Bad page state in process kworker/0:1H pfn:2423a78 page:fffffb03d08e9e00 count:-3 mapcount:0 mapping: (null) index:0x0 flags: 0x57ffffc0000000() raw: 0057ffffc0000000 0000000000000000 0000000000000000 fffffffdffffffff raw: dead000000000100 dead000000000200 0000000000000000 0000000000000000 page dumped because: nonzero _count CPU: 0 PID: 733 Comm: kworker/0:1H Tainted: G I 4.15.0-rc7.bart+ #1 Hardware name: HP ProLiant DL380 G7, BIOS P67 08/16/2015 Workqueue: ib-comp-wq ib_cq_poll_work [ib_core] Call Trace: dump_stack+0x5c/0x83 bad_page+0xf5/0x10f get_page_from_freelist+0xa46/0x11b0 __alloc_pages_nodemask+0x103/0x290 sgl_alloc_order+0x101/0x180 target_alloc_sgl+0x2c/0x40 [target_core_mod] srpt_alloc_rw_ctxs+0x173/0x2d0 [ib_srpt] srpt_handle_new_iu+0x61e/0x7f0 [ib_srpt] __ib_process_cq+0x55/0xa0 [ib_core] ib_cq_poll_work+0x1b/0x60 [ib_core] process_one_work+0x141/0x340 worker_thread+0x47/0x3e0 kthread+0xf5/0x130 ret_from_fork+0x1f/0x30 Fixes: e80a0af4 ("lib/scatterlist: Introduce sgl_alloc() and sgl_free()") Reported-by: NLaurence Oberman <loberman@redhat.com> Tested-by: NLaurence Oberman <loberman@redhat.com> Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com> Cc: Nicholas A. Bellinger <nab@linux-iscsi.org> Cc: Laurence Oberman <loberman@redhat.com> Signed-off-by: NJens Axboe <axboe@kernel.dk>
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- 15 1月, 2018 16 次提交
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由 Christoph Hellwig 提交于
All these symbols are only used by arch dma_ops implementations or xen-swiotlb. None of which can be modular. Signed-off-by: NChristoph Hellwig <hch@lst.de> Acked-by: NChristian König <christian.koenig@amd.com>
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由 Christoph Hellwig 提交于
Factor out a new swiotlb_alloc_buffer helper that allocates DMA coherent memory from the swiotlb bounce buffer. This allows to simplify the swiotlb_alloc implemenation that uses dma_direct_alloc to try to allocate a reachable buffer first. Signed-off-by: NChristoph Hellwig <hch@lst.de> Acked-by: NChristian König <christian.koenig@amd.com>
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由 Christoph Hellwig 提交于
Factor out a new swiotlb_free_buffer helper that checks if an address is allocated from the swiotlb bounce buffer, and if yes frees it. This allows to simplify the swiotlb_free implemenation that uses dma_direct_free to free the non-bounce buffer allocations. Signed-off-by: NChristoph Hellwig <hch@lst.de> Acked-by: NChristian König <christian.koenig@amd.com>
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由 Christoph Hellwig 提交于
To properly reject too small DMA masks based on the addressability of the bounce buffer. Signed-off-by: NChristoph Hellwig <hch@lst.de> Acked-by: NChristian König <christian.koenig@amd.com>
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由 Christoph Hellwig 提交于
Currently all architectures that want to use swiotlb have to implement their own dma_map_ops instances. Provide a generic one based on the x86 implementation which first calls into dma_direct to try a full blown direct mapping implementation (including e.g. CMA) before falling back allocating from the swiotlb buffer. Signed-off-by: NChristoph Hellwig <hch@lst.de> Acked-by: NChristian König <christian.koenig@amd.com>
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由 Christoph Hellwig 提交于
Signed-off-by: NChristoph Hellwig <hch@lst.de> Acked-by: NChristian König <christian.koenig@amd.com> Reviewed-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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由 Christian König 提交于
TTM tries to allocate coherent memory in chunks of 2MB first to improve TLB efficiency and falls back to allocating 4K pages if that fails. Suppress the warning when the 2MB allocations fails since there is a valid fall back path. Signed-off-by: NChristian König <christian.koenig@amd.com> Reported-by: NMike Galbraith <efault@gmx.de> Acked-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com> Bug: https://bugs.freedesktop.org/show_bug.cgi?id=104082 CC: stable@vger.kernel.org Signed-off-by: NChristoph Hellwig <hch@lst.de>
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由 Christoph Hellwig 提交于
Signed-off-by: NChristoph Hellwig <hch@lst.de> Reviewed-by: NRobin Murphy <robin.murphy@arm.com>
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由 Christoph Hellwig 提交于
So that they don't need to indirect through the operation vector. Signed-off-by: NChristoph Hellwig <hch@lst.de> Reviewed-by: NVladimir Murzin <vladimir.murzin@arm.com>
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由 Christoph Hellwig 提交于
If an attempt to allocate memory succeeded, but isn't inside the supported DMA mask, retry the allocation with GFP_DMA set as a last resort. Based on the x86 code, but an off by one error in what is now dma_coherent_ok has been fixed vs the x86 code. Signed-off-by: NChristoph Hellwig <hch@lst.de>
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由 Christoph Hellwig 提交于
This allows to dip into zones for lower memory if they are available. If one of the zones is not available the corresponding GFP_* flag will evaluate to 0 so they won't change anything. We provide an arch tunable for those architectures that do not use GFP_DMA for the lowest 24-bits, given that there are a few. Roughly based on the x86 code. Signed-off-by: NChristoph Hellwig <hch@lst.de>
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由 Christoph Hellwig 提交于
To preserve the x86 behavior. Signed-off-by: NChristoph Hellwig <hch@lst.de> Reviewed-by: NRobin Murphy <robin.murphy@arm.com>
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由 Christoph Hellwig 提交于
Try the CMA allocator for coherent allocations if supported. Roughly modelled after the x86 code. Signed-off-by: NChristoph Hellwig <hch@lst.de>
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由 Christoph Hellwig 提交于
Roughly based on the x86 pci-nommu implementation. Signed-off-by: NChristoph Hellwig <hch@lst.de>
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由 Christoph Hellwig 提交于
This means it uses whatever linear remapping scheme that the architecture provides is used in the generic dma_direct ops. Signed-off-by: NChristoph Hellwig <hch@lst.de> Reviewed-by: NVladimir Murzin <vladimir.murzin@arm.com>
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由 Christoph Hellwig 提交于
The trivial direct mapping implementation already does a virtual to physical translation which isn't strictly a noop, and will soon learn to do non-direct but linear physical to dma translations through the device offset and a few small tricks. Rename it to a better fitting name. Signed-off-by: NChristoph Hellwig <hch@lst.de> Reviewed-by: NVladimir Murzin <vladimir.murzin@arm.com>
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- 13 1月, 2018 3 次提交
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由 Masami Hiramatsu 提交于
Support in-kernel fault-injection framework via debugfs. This allows you to inject a conditional error to specified function using debugfs interfaces. Here is the result of test script described in Documentation/fault-injection/fault-injection.txt =========== # ./test_fail_function.sh 1+0 records in 1+0 records out 1048576 bytes (1.0 MB, 1.0 MiB) copied, 0.0227404 s, 46.1 MB/s btrfs-progs v4.4 See http://btrfs.wiki.kernel.org for more information. Label: (null) UUID: bfa96010-12e9-4360-aed0-42eec7af5798 Node size: 16384 Sector size: 4096 Filesystem size: 1001.00MiB Block group profiles: Data: single 8.00MiB Metadata: DUP 58.00MiB System: DUP 12.00MiB SSD detected: no Incompat features: extref, skinny-metadata Number of devices: 1 Devices: ID SIZE PATH 1 1001.00MiB /dev/loop2 mount: mount /dev/loop2 on /opt/tmpmnt failed: Cannot allocate memory SUCCESS! =========== Signed-off-by: NMasami Hiramatsu <mhiramat@kernel.org> Reviewed-by: NJosef Bacik <jbacik@fb.com> Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
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由 Masami Hiramatsu 提交于
Add injectable error types for each error-injectable function. One motivation of error injection test is to find software flaws, mistakes or mis-handlings of expectable errors. If we find such flaws by the test, that is a program bug, so we need to fix it. But if the tester miss input the error (e.g. just return success code without processing anything), it causes unexpected behavior even if the caller is correctly programmed to handle any errors. That is not what we want to test by error injection. To clarify what type of errors the caller must expect for each injectable function, this introduces injectable error types: - EI_ETYPE_NULL : means the function will return NULL if it fails. No ERR_PTR, just a NULL. - EI_ETYPE_ERRNO : means the function will return -ERRNO if it fails. - EI_ETYPE_ERRNO_NULL : means the function will return -ERRNO (ERR_PTR) or NULL. ALLOW_ERROR_INJECTION() macro is expanded to get one of NULL, ERRNO, ERRNO_NULL to record the error type for each function. e.g. ALLOW_ERROR_INJECTION(open_ctree, ERRNO) This error types are shown in debugfs as below. ==== / # cat /sys/kernel/debug/error_injection/list open_ctree [btrfs] ERRNO io_ctl_init [btrfs] ERRNO ==== Signed-off-by: NMasami Hiramatsu <mhiramat@kernel.org> Reviewed-by: NJosef Bacik <jbacik@fb.com> Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
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由 Masami Hiramatsu 提交于
Since error-injection framework is not limited to be used by kprobes, nor bpf. Other kernel subsystems can use it freely for checking safeness of error-injection, e.g. livepatch, ftrace etc. So this separate error-injection framework from kprobes. Some differences has been made: - "kprobe" word is removed from any APIs/structures. - BPF_ALLOW_ERROR_INJECTION() is renamed to ALLOW_ERROR_INJECTION() since it is not limited for BPF too. - CONFIG_FUNCTION_ERROR_INJECTION is the config item of this feature. It is automatically enabled if the arch supports error injection feature for kprobe or ftrace etc. Signed-off-by: NMasami Hiramatsu <mhiramat@kernel.org> Reviewed-by: NJosef Bacik <jbacik@fb.com> Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
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- 12 1月, 2018 1 次提交
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由 Eric Biggers 提交于
For chacha20_block(), use the existing 32-bit left-rotate function instead of defining one ourselves. Signed-off-by: NEric Biggers <ebiggers@google.com> Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
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- 10 1月, 2018 2 次提交
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由 Christoph Hellwig 提交于
phys_to_dma, dma_to_phys and dma_capable are helpers published by architecture code for use of swiotlb and xen-swiotlb only. Drivers are not supposed to use these directly, but use the DMA API instead. Move these to a new asm/dma-direct.h helper, included by a linux/dma-direct.h wrapper that provides the default linear mapping unless the architecture wants to override it. In the MIPS case the existing dma-coherent.h is reused for now as untangling it will take a bit of work. Signed-off-by: NChristoph Hellwig <hch@lst.de> Acked-by: NRobin Murphy <robin.murphy@arm.com>
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由 Alexei Starovoitov 提交于
The BPF interpreter has been used as part of the spectre 2 attack CVE-2017-5715. A quote from goolge project zero blog: "At this point, it would normally be necessary to locate gadgets in the host kernel code that can be used to actually leak data by reading from an attacker-controlled location, shifting and masking the result appropriately and then using the result of that as offset to an attacker-controlled address for a load. But piecing gadgets together and figuring out which ones work in a speculation context seems annoying. So instead, we decided to use the eBPF interpreter, which is built into the host kernel - while there is no legitimate way to invoke it from inside a VM, the presence of the code in the host kernel's text section is sufficient to make it usable for the attack, just like with ordinary ROP gadgets." To make attacker job harder introduce BPF_JIT_ALWAYS_ON config option that removes interpreter from the kernel in favor of JIT-only mode. So far eBPF JIT is supported by: x64, arm64, arm32, sparc64, s390, powerpc64, mips64 The start of JITed program is randomized and code page is marked as read-only. In addition "constant blinding" can be turned on with net.core.bpf_jit_harden v2->v3: - move __bpf_prog_ret0 under ifdef (Daniel) v1->v2: - fix init order, test_bpf and cBPF (Daniel's feedback) - fix offloaded bpf (Jakub's feedback) - add 'return 0' dummy in case something can invoke prog->bpf_func - retarget bpf tree. For bpf-next the patch would need one extra hunk. It will be sent when the trees are merged back to net-next Considered doing: int bpf_jit_enable __read_mostly = BPF_EBPF_JIT_DEFAULT; but it seems better to land the patch as-is and in bpf-next remove bpf_jit_enable global variable from all JITs, consolidate in one place and remove this jit_init() function. Signed-off-by: NAlexei Starovoitov <ast@kernel.org> Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
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- 09 1月, 2018 2 次提交
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由 Joe Perches 提交于
Convert DEVICE_ATTR uses to DEVICE_ATTR_RW where possible. Done with perl script: $ git grep -w --name-only DEVICE_ATTR | \ xargs perl -i -e 'local $/; while (<>) { s/\bDEVICE_ATTR\s*\(\s*(\w+)\s*,\s*\(?(\s*S_IRUGO\s*\|\s*S_IWUSR|\s*S_IWUSR\s*\|\s*S_IRUGO\s*|\s*0644\s*)\)?\s*,\s*\1_show\s*,\s*\1_store\s*\)/DEVICE_ATTR_RW(\1)/g; print;}' Signed-off-by: NJoe Perches <joe@perches.com> Acked-by: NFelipe Balbi <felipe.balbi@linux.intel.com> Acked-by: NAndy Shevchenko <andy.shevchenko@gmail.com> Acked-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Acked-by: NZhang Rui <rui.zhang@intel.com> Acked-by: NJarkko Nikula <jarkko.nikula@bitmer.com> Acked-by: NJani Nikula <jani.nikula@intel.com> Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
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由 Sergey Senozhatsky 提交于
dereference_symbol_descriptor() invokes appropriate ARCH specific function descriptor dereference callbacks: - dereference_kernel_function_descriptor() if the pointer is a kernel symbol; - dereference_module_function_descriptor() if the pointer is a module symbol. This is the last step needed to make '%pS/%ps' smart enough to handle function descriptor dereference on affected ARCHs and to retire '%pF/%pf'. To refresh it: Some architectures (ia64, ppc64, parisc64) use an indirect pointer for C function pointers - the function pointer points to a function descriptor and we need to dereference it to get the actual function pointer. Function descriptors live in .opd elf section and all affected ARCHs (ia64, ppc64, parisc64) handle it properly for kernel and modules. So we, technically, can decide if the dereference is needed by simply looking at the pointer: if it belongs to .opd section then we need to dereference it. The kernel and modules have their own .opd sections, obviously, that's why we need to split dereference_function_descriptor() and use separate kernel and module dereference arch callbacks. Link: http://lkml.kernel.org/r/20171206043649.GB15885@jagdpanzerIV Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: James Bottomley <jejb@parisc-linux.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Jessica Yu <jeyu@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: linux-ia64@vger.kernel.org Cc: linux-parisc@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-kernel@vger.kernel.org Signed-off-by: NSergey Senozhatsky <sergey.senozhatsky@gmail.com> Tested-by: Tony Luck <tony.luck@intel.com> #ia64 Tested-by: Santosh Sivaraj <santosh@fossix.org> #powerpc Tested-by: Helge Deller <deller@gmx.de> #parisc64 Signed-off-by: NPetr Mladek <pmladek@suse.com>
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- 08 1月, 2018 1 次提交
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由 Andrew Morton 提交于
In support of a soon to be published MFD driver using serdev to talk to a supervisory processor that uses the CCITT-FALSE CRC16 variant in it's protocol, this patch was tested successfully on an i.MX6 ARM platform. Link: http://lkml.kernel.org/r/20170413142932.27287-1-andrew.smirnov@gmail.comSigned-off-by: NAndrey Vostrikov <andrey.vostrikov@cogentembedded.com> Signed-off-by: NAndrey Smirnov <andrew.smirnov@gmail.com> Tested-by: NChris Healy <cphealy@gmail.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLee Jones <lee.jones@linaro.org>
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- 07 1月, 2018 1 次提交
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由 Bart Van Assche 提交于
Many kernel drivers contain code that allocates and frees both a scatterlist and the pages that populate that scatterlist. Introduce functions in lib/scatterlist.c that perform these tasks instead of duplicating this functionality in multiple drivers. Only include these functions in the build if CONFIG_SGL_ALLOC=y to avoid that the kernel size increases if this functionality is not used. Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com> Reviewed-by: NHannes Reinecke <hare@suse.com> Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de> Signed-off-by: NJens Axboe <axboe@kernel.dk>
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