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2016-06-24tree wide: get rid of __GFP_REPEAT for order-0 allocations part IMichal Hocko
This is the third version of the patchset previously sent [1]. I have basically only rebased it on top of 4.7-rc1 tree and dropped "dm: get rid of superfluous gfp flags" which went through dm tree. I am sending it now because it is tree wide and chances for conflicts are reduced considerably when we want to target rc2. I plan to send the next step and rename the flag and move to a better semantic later during this release cycle so we will have a new semantic ready for 4.8 merge window hopefully. Motivation: While working on something unrelated I've checked the current usage of __GFP_REPEAT in the tree. It seems that a majority of the usage is and always has been bogus because __GFP_REPEAT has always been about costly high order allocations while we are using it for order-0 or very small orders very often. It seems that a big pile of them is just a copy&paste when a code has been adopted from one arch to another. I think it makes some sense to get rid of them because they are just making the semantic more unclear. Please note that GFP_REPEAT is documented as * __GFP_REPEAT: Try hard to allocate the memory, but the allocation attempt * _might_ fail. This depends upon the particular VM implementation. while !costly requests have basically nofail semantic. So one could reasonably expect that order-0 request with __GFP_REPEAT will not loop for ever. This is not implemented right now though. I would like to move on with __GFP_REPEAT and define a better semantic for it. $ git grep __GFP_REPEAT origin/master | wc -l 111 $ git grep __GFP_REPEAT | wc -l 36 So we are down to the third after this patch series. The remaining places really seem to be relying on __GFP_REPEAT due to large allocation requests. This still needs some double checking which I will do later after all the simple ones are sorted out. I am touching a lot of arch specific code here and I hope I got it right but as a matter of fact I even didn't compile test for some archs as I do not have cross compiler for them. Patches should be quite trivial to review for stupid compile mistakes though. The tricky parts are usually hidden by macro definitions and thats where I would appreciate help from arch maintainers. [1] http://lkml.kernel.org/r/1461849846-27209-1-git-send-email-mhocko@kernel.org This patch (of 19): __GFP_REPEAT has a rather weak semantic but since it has been introduced around 2.6.12 it has been ignored for low order allocations. Yet we have the full kernel tree with its usage for apparently order-0 allocations. This is really confusing because __GFP_REPEAT is explicitly documented to allow allocation failures which is a weaker semantic than the current order-0 has (basically nofail). Let's simply drop __GFP_REPEAT from those places. This would allow to identify place which really need allocator to retry harder and formulate a more specific semantic for what the flag is supposed to do actually. Link: http://lkml.kernel.org/r/1464599699-30131-2-git-send-email-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Andy Lutomirski <luto@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chen Liqin <liqin.linux@gmail.com> Cc: Chris Metcalf <cmetcalf@mellanox.com> [for tile] Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Helge Deller <deller@gmx.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jan Kara <jack@suse.cz> Cc: John Crispin <blogic@openwrt.org> Cc: Lennox Wu <lennox.wu@gmail.com> Cc: Ley Foon Tan <lftan@altera.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Rich Felker <dalias@libc.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-24Merge tag 'asm-generic-4.7' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic Pull asm-generic cleanup from Arnd Bergmann: "I have only one patch for asm-generic in this release, this one is from James Hogan and updates the generic system call table for renameat2 so we don't need to provide both renameat and renameat2 in newly added architectures" * tag 'asm-generic-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: asm-generic: Drop renameat syscall from default list
2016-05-20lib/GCD.c: use binary GCD algorithm instead of EuclideanZhaoxiu Zeng
The binary GCD algorithm is based on the following facts: 1. If a and b are all evens, then gcd(a,b) = 2 * gcd(a/2, b/2) 2. If a is even and b is odd, then gcd(a,b) = gcd(a/2, b) 3. If a and b are all odds, then gcd(a,b) = gcd((a-b)/2, b) = gcd((a+b)/2, b) Even on x86 machines with reasonable division hardware, the binary algorithm runs about 25% faster (80% the execution time) than the division-based Euclidian algorithm. On platforms like Alpha and ARMv6 where division is a function call to emulation code, it's even more significant. There are two variants of the code here, depending on whether a fast __ffs (find least significant set bit) instruction is available. This allows the unpredictable branches in the bit-at-a-time shifting loop to be eliminated. If fast __ffs is not available, the "even/odd" GCD variant is used. I use the following code to benchmark: #include <stdio.h> #include <stdlib.h> #include <stdint.h> #include <string.h> #include <time.h> #include <unistd.h> #define swap(a, b) \ do { \ a ^= b; \ b ^= a; \ a ^= b; \ } while (0) unsigned long gcd0(unsigned long a, unsigned long b) { unsigned long r; if (a < b) { swap(a, b); } if (b == 0) return a; while ((r = a % b) != 0) { a = b; b = r; } return b; } unsigned long gcd1(unsigned long a, unsigned long b) { unsigned long r = a | b; if (!a || !b) return r; b >>= __builtin_ctzl(b); for (;;) { a >>= __builtin_ctzl(a); if (a == b) return a << __builtin_ctzl(r); if (a < b) swap(a, b); a -= b; } } unsigned long gcd2(unsigned long a, unsigned long b) { unsigned long r = a | b; if (!a || !b) return r; r &= -r; while (!(b & r)) b >>= 1; for (;;) { while (!(a & r)) a >>= 1; if (a == b) return a; if (a < b) swap(a, b); a -= b; a >>= 1; if (a & r) a += b; a >>= 1; } } unsigned long gcd3(unsigned long a, unsigned long b) { unsigned long r = a | b; if (!a || !b) return r; b >>= __builtin_ctzl(b); if (b == 1) return r & -r; for (;;) { a >>= __builtin_ctzl(a); if (a == 1) return r & -r; if (a == b) return a << __builtin_ctzl(r); if (a < b) swap(a, b); a -= b; } } unsigned long gcd4(unsigned long a, unsigned long b) { unsigned long r = a | b; if (!a || !b) return r; r &= -r; while (!(b & r)) b >>= 1; if (b == r) return r; for (;;) { while (!(a & r)) a >>= 1; if (a == r) return r; if (a == b) return a; if (a < b) swap(a, b); a -= b; a >>= 1; if (a & r) a += b; a >>= 1; } } static unsigned long (*gcd_func[])(unsigned long a, unsigned long b) = { gcd0, gcd1, gcd2, gcd3, gcd4, }; #define TEST_ENTRIES (sizeof(gcd_func) / sizeof(gcd_func[0])) #if defined(__x86_64__) #define rdtscll(val) do { \ unsigned long __a,__d; \ __asm__ __volatile__("rdtsc" : "=a" (__a), "=d" (__d)); \ (val) = ((unsigned long long)__a) | (((unsigned long long)__d)<<32); \ } while(0) static unsigned long long benchmark_gcd_func(unsigned long (*gcd)(unsigned long, unsigned long), unsigned long a, unsigned long b, unsigned long *res) { unsigned long long start, end; unsigned long long ret; unsigned long gcd_res; rdtscll(start); gcd_res = gcd(a, b); rdtscll(end); if (end >= start) ret = end - start; else ret = ~0ULL - start + 1 + end; *res = gcd_res; return ret; } #else static inline struct timespec read_time(void) { struct timespec time; clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &time); return time; } static inline unsigned long long diff_time(struct timespec start, struct timespec end) { struct timespec temp; if ((end.tv_nsec - start.tv_nsec) < 0) { temp.tv_sec = end.tv_sec - start.tv_sec - 1; temp.tv_nsec = 1000000000ULL + end.tv_nsec - start.tv_nsec; } else { temp.tv_sec = end.tv_sec - start.tv_sec; temp.tv_nsec = end.tv_nsec - start.tv_nsec; } return temp.tv_sec * 1000000000ULL + temp.tv_nsec; } static unsigned long long benchmark_gcd_func(unsigned long (*gcd)(unsigned long, unsigned long), unsigned long a, unsigned long b, unsigned long *res) { struct timespec start, end; unsigned long gcd_res; start = read_time(); gcd_res = gcd(a, b); end = read_time(); *res = gcd_res; return diff_time(start, end); } #endif static inline unsigned long get_rand() { if (sizeof(long) == 8) return (unsigned long)rand() << 32 | rand(); else return rand(); } int main(int argc, char **argv) { unsigned int seed = time(0); int loops = 100; int repeats = 1000; unsigned long (*res)[TEST_ENTRIES]; unsigned long long elapsed[TEST_ENTRIES]; int i, j, k; for (;;) { int opt = getopt(argc, argv, "n:r:s:"); /* End condition always first */ if (opt == -1) break; switch (opt) { case 'n': loops = atoi(optarg); break; case 'r': repeats = atoi(optarg); break; case 's': seed = strtoul(optarg, NULL, 10); break; default: /* You won't actually get here. */ break; } } res = malloc(sizeof(unsigned long) * TEST_ENTRIES * loops); memset(elapsed, 0, sizeof(elapsed)); srand(seed); for (j = 0; j < loops; j++) { unsigned long a = get_rand(); /* Do we have args? */ unsigned long b = argc > optind ? strtoul(argv[optind], NULL, 10) : get_rand(); unsigned long long min_elapsed[TEST_ENTRIES]; for (k = 0; k < repeats; k++) { for (i = 0; i < TEST_ENTRIES; i++) { unsigned long long tmp = benchmark_gcd_func(gcd_func[i], a, b, &res[j][i]); if (k == 0 || min_elapsed[i] > tmp) min_elapsed[i] = tmp; } } for (i = 0; i < TEST_ENTRIES; i++) elapsed[i] += min_elapsed[i]; } for (i = 0; i < TEST_ENTRIES; i++) printf("gcd%d: elapsed %llu\n", i, elapsed[i]); k = 0; srand(seed); for (j = 0; j < loops; j++) { unsigned long a = get_rand(); unsigned long b = argc > optind ? strtoul(argv[optind], NULL, 10) : get_rand(); for (i = 1; i < TEST_ENTRIES; i++) { if (res[j][i] != res[j][0]) break; } if (i < TEST_ENTRIES) { if (k == 0) { k = 1; fprintf(stderr, "Error:\n"); } fprintf(stderr, "gcd(%lu, %lu): ", a, b); for (i = 0; i < TEST_ENTRIES; i++) fprintf(stderr, "%ld%s", res[j][i], i < TEST_ENTRIES - 1 ? ", " : "\n"); } } if (k == 0) fprintf(stderr, "PASS\n"); free(res); return 0; } Compiled with "-O2", on "VirtualBox 4.4.0-22-generic #38-Ubuntu x86_64" got: zhaoxiuzeng@zhaoxiuzeng-VirtualBox:~/develop$ ./gcd -r 500000 -n 10 gcd0: elapsed 10174 gcd1: elapsed 2120 gcd2: elapsed 2902 gcd3: elapsed 2039 gcd4: elapsed 2812 PASS zhaoxiuzeng@zhaoxiuzeng-VirtualBox:~/develop$ ./gcd -r 500000 -n 10 gcd0: elapsed 9309 gcd1: elapsed 2280 gcd2: elapsed 2822 gcd3: elapsed 2217 gcd4: elapsed 2710 PASS zhaoxiuzeng@zhaoxiuzeng-VirtualBox:~/develop$ ./gcd -r 500000 -n 10 gcd0: elapsed 9589 gcd1: elapsed 2098 gcd2: elapsed 2815 gcd3: elapsed 2030 gcd4: elapsed 2718 PASS zhaoxiuzeng@zhaoxiuzeng-VirtualBox:~/develop$ ./gcd -r 500000 -n 10 gcd0: elapsed 9914 gcd1: elapsed 2309 gcd2: elapsed 2779 gcd3: elapsed 2228 gcd4: elapsed 2709 PASS [akpm@linux-foundation.org: avoid #defining a CONFIG_ variable] Signed-off-by: Zhaoxiu Zeng <zhaoxiu.zeng@gmail.com> Signed-off-by: George Spelvin <linux@horizon.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-20exit_thread: remove empty bodiesJiri Slaby
Define HAVE_EXIT_THREAD for archs which want to do something in exit_thread. For others, let's define exit_thread as an empty inline. This is a cleanup before we change the prototype of exit_thread to accept a task parameter. [akpm@linux-foundation.org: fix mips] Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: "David S. Miller" <davem@davemloft.net> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Aurelien Jacquiot <a-jacquiot@ti.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chen Liqin <liqin.linux@gmail.com> Cc: Chris Metcalf <cmetcalf@mellanox.com> Cc: Chris Zankel <chris@zankel.net> Cc: David Howells <dhowells@redhat.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Cc: Haavard Skinnemoen <hskinnemoen@gmail.com> Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Helge Deller <deller@gmx.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: James Hogan <james.hogan@imgtec.com> Cc: Jeff Dike <jdike@addtoit.com> Cc: Jesper Nilsson <jesper.nilsson@axis.com> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Jonas Bonn <jonas@southpole.se> Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com> Cc: Lennox Wu <lennox.wu@gmail.com> Cc: Ley Foon Tan <lftan@altera.com> Cc: Mark Salter <msalter@redhat.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Matt Turner <mattst88@gmail.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Mikael Starvik <starvik@axis.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Rich Felker <dalias@libc.org> Cc: Richard Henderson <rth@twiddle.net> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: Richard Weinberger <richard@nod.at> Cc: Russell King <linux@arm.linux.org.uk> Cc: Steven Miao <realmz6@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-05asm-generic: Drop renameat syscall from default listJames Hogan
The newer renameat2 syscall provides all the functionality provided by the renameat syscall and adds flags, so future architectures won't need to include renameat. Therefore drop the renameat syscall from the generic syscall list unless __ARCH_WANT_RENAMEAT is defined by the architecture's unistd.h prior to including asm-generic/unistd.h, and adjust all architectures using the generic syscall list to define it so that no in-tree architectures are affected. Signed-off-by: James Hogan <james.hogan@imgtec.com> Acked-by: Vineet Gupta <vgupta@synopsys.com> Cc: linux-arch@vger.kernel.org Cc: linux-snps-arc@lists.infradead.org Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-arm-kernel@lists.infradead.org Cc: Mark Salter <msalter@redhat.com> Cc: Aurelien Jacquiot <a-jacquiot@ti.com> Cc: linux-c6x-dev@linux-c6x.org Cc: Richard Kuo <rkuo@codeaurora.org> Cc: linux-hexagon@vger.kernel.org Cc: linux-metag@vger.kernel.org Cc: Jonas Bonn <jonas@southpole.se> Cc: linux@lists.openrisc.net Cc: Chen Liqin <liqin.linux@gmail.com> Cc: Lennox Wu <lennox.wu@gmail.com> Cc: Chris Metcalf <cmetcalf@mellanox.com> Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Cc: Ley Foon Tan <lftan@altera.com> Cc: nios2-dev@lists.rocketboards.org Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: uclinux-h8-devel@lists.sourceforge.jp Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2016-04-22openrisc: drop wrongly typed definition of page_to_virt()Ard Biesheuvel
To align with generic code and other architectures that expect the macro page_to_virt to produce an expression whose type is 'void*', drop the arch specific definition, which is never referenced anyway. Acked-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-03-25arch, ftrace: for KASAN put hard/soft IRQ entries into separate sectionsAlexander Potapenko
KASAN needs to know whether the allocation happens in an IRQ handler. This lets us strip everything below the IRQ entry point to reduce the number of unique stack traces needed to be stored. Move the definition of __irq_entry to <linux/interrupt.h> so that the users don't need to pull in <linux/ftrace.h>. Also introduce the __softirq_entry macro which is similar to __irq_entry, but puts the corresponding functions to the .softirqentry.text section. Signed-off-by: Alexander Potapenko <glider@google.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Andrey Konovalov <adech.fo@gmail.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Konstantin Serebryany <kcc@google.com> Cc: Dmitry Chernenkov <dmitryc@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-24Merge tag 'asm-generic-4.6' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic Pull asm-generic updates from Arnd Bergmann: "There are only three patches this time, most other changes to files in include/asm-generic tend to go through the tree of whoever depends on the change. Two patches are cleanups for stuff that is no longer needed, the main change is to adapt the generic version of BUG_ON() for CONFIG_BUG=n to make it behave consistently with BUG(). This avoids undefined behavior along with a number of warnings about that undefined behavior in randconfig builds when we keep going on after hitting a BUG_ON()" * tag 'asm-generic-4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: asm-generic: remove old nonatomic-io wrapper files asm-generic: default BUG_ON(x) to if(x)BUG() asm-generic: page.h: Remove useless get_user_page and free_user_page
2016-02-26asm-generic: page.h: Remove useless get_user_page and free_user_pageChen Gang
They are not symmetric with each other, neither are used in real world (can not be found by grep command in source code root directory), so remove them. Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com> Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> Acked-by: Greg Ungerer <gerg@uclinux.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2016-02-16gpio: Remove unused asm/gpio.h filesBjorn Helgaas
asm/gpio.h is included only by linux/gpio.h, and then only when the arch selects ARCH_HAVE_CUSTOM_GPIO_H. Only the following arches select it: arm avr32 blackfin m68k (COLDFIRE only) sh unicore32. Remove the unused asm/gpio.h files for the arches that do not select ARCH_HAVE_CUSTOM_GPIO_H. This is a follow-on to 7563bbf89d06 ("gpiolib/arches: Centralise bolierplate asm/gpio.h"). Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-01-20dma-mapping: always provide the dma_map_ops based implementationChristoph Hellwig
Move the generic implementation to <linux/dma-mapping.h> now that all architectures support it and remove the HAVE_DMA_ATTR Kconfig symbol now that everyone supports them. [valentinrothberg@gmail.com: remove leftovers in Kconfig] Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: "David S. Miller" <davem@davemloft.net> Cc: Aurelien Jacquiot <a-jacquiot@ti.com> Cc: Chris Metcalf <cmetcalf@ezchip.com> Cc: David Howells <dhowells@redhat.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Haavard Skinnemoen <hskinnemoen@gmail.com> Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no> Cc: Helge Deller <deller@gmx.de> Cc: James Hogan <james.hogan@imgtec.com> Cc: Jesper Nilsson <jesper.nilsson@axis.com> Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com> Cc: Ley Foon Tan <lftan@altera.com> Cc: Mark Salter <msalter@redhat.com> Cc: Mikael Starvik <starvik@axis.com> Cc: Steven Miao <realmz6@gmail.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Joerg Roedel <jroedel@suse.de> Cc: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Valentin Rothberg <valentinrothberg@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-10dma-mapping: consolidate dma_set_maskChristoph Hellwig
Almost everyone implements dma_set_mask the same way, although some time that's hidden in ->set_dma_mask methods. This patch consolidates those into a common implementation that either calls ->set_dma_mask if present or otherwise uses the default implementation. Some architectures used to only call ->set_dma_mask after the initial checks, and those instance have been fixed to do the full work. h8300 implemented dma_set_mask bogusly as a no-ops and has been fixed. Unfortunately some architectures overload unrelated semantics like changing the dma_ops into it so we still need to allow for an architecture override for now. [jcmvbkbc@gmail.com: fix xtensa] Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Russell King <linux@arm.linux.org.uk> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Michal Simek <monstr@monstr.eu> Cc: Jonas Bonn <jonas@southpole.se> Cc: Chris Metcalf <cmetcalf@ezchip.com> Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-10dma-mapping: consolidate dma_supportedChristoph Hellwig
Most architectures just call into ->dma_supported, but some also return 1 if the method is not present, or 0 if no dma ops are present (although that should never happeb). Consolidate this more broad version into common code. Also fix h8300 which inorrectly always returned 0, which would have been a problem if it's dma_set_mask implementation wasn't a similarly buggy noop. As a few architectures have much more elaborate implementations, we still allow for arch overrides. [jcmvbkbc@gmail.com: fix xtensa] Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Russell King <linux@arm.linux.org.uk> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Michal Simek <monstr@monstr.eu> Cc: Jonas Bonn <jonas@southpole.se> Cc: Chris Metcalf <cmetcalf@ezchip.com> Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-10dma-mapping: cosolidate dma_mapping_errorChristoph Hellwig
Currently there are three valid implementations of dma_mapping_error: (1) call ->mapping_error (2) check for a hardcoded error code (3) always return 0 This patch provides a common implementation that calls ->mapping_error if present, then checks for DMA_ERROR_CODE if defined or otherwise returns 0. [jcmvbkbc@gmail.com: fix xtensa] Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Russell King <linux@arm.linux.org.uk> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Michal Simek <monstr@monstr.eu> Cc: Jonas Bonn <jonas@southpole.se> Cc: Chris Metcalf <cmetcalf@ezchip.com> Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-10dma-mapping: consolidate dma_{alloc,free}_noncoherentChristoph Hellwig
Most architectures do not support non-coherent allocations and either define dma_{alloc,free}_noncoherent to their coherent versions or stub them out. Openrisc uses dma_{alloc,free}_attrs to implement them, and only Mips implements them directly. This patch moves the Openrisc version to common code, and handles the DMA_ATTR_NON_CONSISTENT case in the mips dma_map_ops instance. Note that actual non-coherent allocations require a dma_cache_sync implementation, so if non-coherent allocations didn't work on an architecture before this patch they still won't work after it. [jcmvbkbc@gmail.com: fix xtensa] Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Russell King <linux@arm.linux.org.uk> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Michal Simek <monstr@monstr.eu> Cc: Jonas Bonn <jonas@southpole.se> Cc: Chris Metcalf <cmetcalf@ezchip.com> Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-10dma-mapping: consolidate dma_{alloc,free}_{attrs,coherent}Christoph Hellwig
Since 2009 we have a nice asm-generic header implementing lots of DMA API functions for architectures using struct dma_map_ops, but unfortunately it's still missing a lot of APIs that all architectures still have to duplicate. This series consolidates the remaining functions, although we still need arch opt outs for two of them as a few architectures have very non-standard implementations. This patch (of 5): The coherent DMA allocator works the same over all architectures supporting dma_map operations. This patch consolidates them and converges the minor differences: - the debug_dma helpers are now called from all architectures, including those that were previously missing them - dma_alloc_from_coherent and dma_release_from_coherent are now always called from the generic alloc/free routines instead of the ops dma-mapping-common.h always includes dma-coherent.h to get the defintions for them, or the stubs if the architecture doesn't support this feature - checks for ->alloc / ->free presence are removed. There is only one magic instead of dma_map_ops without them (mic_dma_ops) and that one is x86 only anyway. Besides that only x86 needs special treatment to replace a default devices if none is passed and tweak the gfp_flags. An optional arch hook is provided for that. [linux@roeck-us.net: fix build] [jcmvbkbc@gmail.com: fix xtensa] Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Russell King <linux@arm.linux.org.uk> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Michal Simek <monstr@monstr.eu> Cc: Jonas Bonn <jonas@southpole.se> Cc: Chris Metcalf <cmetcalf@ezchip.com> Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-08-10openrisc/time: Migrate to new 'set-state' interfaceViresh Kumar
Migrate openrisc driver to the new 'set-state' interface provided by clockevents core, the earlier 'set-mode' interface is marked obsolete now. This also enables us to implement callbacks for new states of clockevent devices, for example: ONESHOT_STOPPED. We weren't doing anything in the ->set_mode() callback. So, this patch doesn't provide any set-state callbacks. Cc: Jonas Bonn <jonas@southpole.se> Cc: linux@lists.openrisc.net Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2015-07-17mm: clean up per architecture MM hook header filesLaurent Dufour
Commit 2ae416b142b6 ("mm: new mm hook framework") introduced an empty header file (mm-arch-hooks.h) for every architecture, even those which doesn't need to define mm hooks. As suggested by Geert Uytterhoeven, this could be cleaned through the use of a generic header file included via each per architecture asm/include/Kbuild file. The PowerPC architecture is not impacted here since this architecture has to defined the arch_remap MM hook. Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com> Suggested-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Vineet Gupta <vgupta@synopsys.com> Cc: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-07-17openrisc: fix CONFIG_UID16 settingAndrew Morton
openrisc-allnoconfig: kernel/uid16.c: In function 'SYSC_setgroups16': kernel/uid16.c:184:2: error: implicit declaration of function 'groups_alloc' kernel/uid16.c:184:13: warning: assignment makes pointer from integer without a cast openrisc shouldn't be setting CONFIG_UID16 when CONFIG_MULTIUSER=n. Fixes: 2813893f8b197a1 ("kernel: conditionally support non-root users, groups and capabilities") Reported-by: Fengguang Wu <fengguang.wu@gmail.com> Cc: Iulia Manda <iulia.manda21@gmail.com> Cc: Josh Triplett <josh@joshtriplett.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-06-25Merge branch 'for-4.2/sg' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull asm/scatterlist.h removal from Jens Axboe: "We don't have any specific arch scatterlist anymore, since parisc finally switched over. Kill the include" * 'for-4.2/sg' of git://git.kernel.dk/linux-block: remove scatterlist.h generation from arch Kbuild files remove <asm/scatterlist.h>
2015-06-24mm: new mm hook frameworkLaurent Dufour
CRIU is recreating the process memory layout by remapping the checkpointee memory area on top of the current process (criu). This includes remapping the vDSO to the place it has at checkpoint time. However some architectures like powerpc are keeping a reference to the vDSO base address to build the signal return stack frame by calling the vDSO sigreturn service. So once the vDSO has been moved, this reference is no more valid and the signal frame built later are not usable. This patch serie is introducing a new mm hook framework, and a new arch_remap hook which is called when mremap is done and the mm lock still hold. The next patch is adding the vDSO remap and unmap tracking to the powerpc architecture. This patch (of 3): This patch introduces a new set of header file to manage mm hooks: - per architecture empty header file (arch/x/include/asm/mm-arch-hooks.h) - a generic header (include/linux/mm-arch-hooks.h) The architecture which need to overwrite a hook as to redefine it in its header file, while architecture which doesn't need have nothing to do. The default hooks are defined in the generic header and are used in the case the architecture is not defining it. In a next step, mm hooks defined in include/asm-generic/mm_hooks.h should be moved here. Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com> Suggested-by: Andrew Morton <akpm@linux-foundation.org> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Hugh Dickins <hughd@google.com> Cc: Rik van Riel <riel@redhat.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Ingo Molnar <mingo@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-05-19remove scatterlist.h generation from arch Kbuild filesChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de> Reported-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-04-15Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge second patchbomb from Andrew Morton: - the rest of MM - various misc bits - add ability to run /sbin/reboot at reboot time - printk/vsprintf changes - fiddle with seq_printf() return value * akpm: (114 commits) parisc: remove use of seq_printf return value lru_cache: remove use of seq_printf return value tracing: remove use of seq_printf return value cgroup: remove use of seq_printf return value proc: remove use of seq_printf return value s390: remove use of seq_printf return value cris fasttimer: remove use of seq_printf return value cris: remove use of seq_printf return value openrisc: remove use of seq_printf return value ARM: plat-pxa: remove use of seq_printf return value nios2: cpuinfo: remove use of seq_printf return value microblaze: mb: remove use of seq_printf return value ipc: remove use of seq_printf return value rtc: remove use of seq_printf return value power: wakeup: remove use of seq_printf return value x86: mtrr: if: remove use of seq_printf return value linux/bitmap.h: improve BITMAP_{LAST,FIRST}_WORD_MASK MAINTAINERS: CREDITS: remove Stefano Brivio from B43 .mailmap: add Ricardo Ribalda CREDITS: add Ricardo Ribalda Delgado ...
2015-04-15openrisc: remove use of seq_printf return valueJoe Perches
The seq_printf return value, because it's frequently misused, will eventually be converted to void. See: commit 1f33c41c03da ("seq_file: Rename seq_overflow() to seq_has_overflowed() and make public") Signed-off-by: Joe Perches <joe@perches.com> Cc: Jonas Bonn <jonas@southpole.se> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-15Merge branch 'exec_domain_rip_v2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rw/misc Pull exec domain removal from Richard Weinberger: "This series removes execution domain support from Linux. The idea behind exec domains was to support different ABIs. The feature was never complete nor stable. Let's rip it out and make the kernel signal handling code less complicated" * 'exec_domain_rip_v2' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/misc: (27 commits) arm64: Removed unused variable sparc: Fix execution domain removal Remove rest of exec domains. arch: Remove exec_domain from remaining archs arc: Remove signal translation and exec_domain xtensa: Remove signal translation and exec_domain xtensa: Autogenerate offsets in struct thread_info x86: Remove signal translation and exec_domain unicore32: Remove signal translation and exec_domain um: Remove signal translation and exec_domain tile: Remove signal translation and exec_domain sparc: Remove signal translation and exec_domain sh: Remove signal translation and exec_domain s390: Remove signal translation and exec_domain mn10300: Remove signal translation and exec_domain microblaze: Remove signal translation and exec_domain m68k: Remove signal translation and exec_domain m32r: Remove signal translation and exec_domain m32r: Autogenerate offsets in struct thread_info frv: Remove signal translation and exec_domain ...
2015-04-12arch: Remove exec_domain from remaining archsRichard Weinberger
Signed-off-by: Richard Weinberger <richard@nod.at>
2015-04-11whack-a-mole: no need to set_fs(USER_DS) in {start,flush}_thread()Al Viro
flush_old_exec() has already done that. Back on 2011 a bunch of instances like that had been kicked out, but that hadn't taken care of then-out-of-tree architectures, obviously, and they served as reinfection vector... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-02-18Merge tag 'asm-generic-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic Pull asm-generic uaccess.h cleanup from Arnd Bergmann: "Like in 3.19, I once more have a multi-stage cleanup for one asm-generic header file, this time the work was done by Michael Tsirkin and cleans up the uaccess.h file in asm-generic, as well as all architectures for which the respective maintainers did not pick up his patches directly" * tag 'asm-generic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: (37 commits) sparc32: nocheck uaccess coding style tweaks sparc64: nocheck uaccess coding style tweaks xtensa: macro whitespace fixes sh: macro whitespace fixes parisc: macro whitespace fixes m68k: macro whitespace fixes m32r: macro whitespace fixes frv: macro whitespace fixes cris: macro whitespace fixes avr32: macro whitespace fixes arm64: macro whitespace fixes arm: macro whitespace fixes alpha: macro whitespace fixes blackfin: macro whitespace fixes sparc64: uaccess_64 macro whitespace fixes sparc32: uaccess_32 macro whitespace fixes avr32: whitespace fix sh: fix put_user sparse errors metag: fix put_user sparse errors ia64: fix put_user sparse errors ...
2015-02-12all arches, signal: move restart_block to struct task_structAndy Lutomirski
If an attacker can cause a controlled kernel stack overflow, overwriting the restart block is a very juicy exploit target. This is because the restart_block is held in the same memory allocation as the kernel stack. Moving the restart block to struct task_struct prevents this exploit by making the restart_block harder to locate. Note that there are other fields in thread_info that are also easy targets, at least on some architectures. It's also a decent simplification, since the restart code is more or less identical on all architectures. [james.hogan@imgtec.com: metag: align thread_info::supervisor_stack] Signed-off-by: Andy Lutomirski <luto@amacapital.net> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Kees Cook <keescook@chromium.org> Cc: David Miller <davem@davemloft.net> Acked-by: Richard Weinberger <richard@nod.at> Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Matt Turner <mattst88@gmail.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Haavard Skinnemoen <hskinnemoen@gmail.com> Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no> Cc: Steven Miao <realmz6@gmail.com> Cc: Mark Salter <msalter@redhat.com> Cc: Aurelien Jacquiot <a-jacquiot@ti.com> Cc: Mikael Starvik <starvik@axis.com> Cc: Jesper Nilsson <jesper.nilsson@axis.com> Cc: David Howells <dhowells@redhat.com> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Michal Simek <monstr@monstr.eu> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Jonas Bonn <jonas@southpole.se> Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Helge Deller <deller@gmx.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc) Tested-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc) Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Chen Liqin <liqin.linux@gmail.com> Cc: Lennox Wu <lennox.wu@gmail.com> Cc: Chris Metcalf <cmetcalf@ezchip.com> Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Cc: Chris Zankel <chris@zankel.net> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Guenter Roeck <linux@roeck-us.net> Signed-off-by: James Hogan <james.hogan@imgtec.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-11mm: make FIRST_USER_ADDRESS unsigned long on all archsKirill A. Shutemov
LKP has triggered a compiler warning after my recent patch "mm: account pmd page tables to the process": mm/mmap.c: In function 'exit_mmap': >> mm/mmap.c:2857:2: warning: right shift count >= width of type [enabled by default] The code: > 2857 WARN_ON(mm_nr_pmds(mm) > 2858 round_up(FIRST_USER_ADDRESS, PUD_SIZE) >> PUD_SHIFT); In this, on tile, we have FIRST_USER_ADDRESS defined as 0. round_up() has the same type -- int. PUD_SHIFT. I think the best way to fix it is to define FIRST_USER_ADDRESS as unsigned long. On every arch for consistency. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reported-by: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-10openrisc: drop _PAGE_FILE and pte_file()-related helpersKirill A. Shutemov
We've replaced remap_file_pages(2) implementation with emulation. Nobody creates non-linear mapping anymore. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Jonas Bonn <jonas@southpole.se> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-01-29vm: add VM_FAULT_SIGSEGV handling supportLinus Torvalds
The core VM already knows about VM_FAULT_SIGBUS, but cannot return a "you should SIGSEGV" error, because the SIGSEGV case was generally handled by the caller - usually the architecture fault handler. That results in lots of duplication - all the architecture fault handlers end up doing very similar "look up vma, check permissions, do retries etc" - but it generally works. However, there are cases where the VM actually wants to SIGSEGV, and applications _expect_ SIGSEGV. In particular, when accessing the stack guard page, libsigsegv expects a SIGSEGV. And it usually got one, because the stack growth is handled by that duplicated architecture fault handler. However, when the generic VM layer started propagating the error return from the stack expansion in commit fee7e49d4514 ("mm: propagate error from stack expansion even for guard page"), that now exposed the existing VM_FAULT_SIGBUS result to user space. And user space really expected SIGSEGV, not SIGBUS. To fix that case, we need to add a VM_FAULT_SIGSEGV, and teach all those duplicate architecture fault handlers about it. They all already have the code to handle SIGSEGV, so it's about just tying that new return value to the existing code, but it's all a bit annoying. This is the mindless minimal patch to do this. A more extensive patch would be to try to gather up the mostly shared fault handling logic into one generic helper routine, and long-term we really should do that cleanup. Just from this patch, you can generally see that most architectures just copied (directly or indirectly) the old x86 way of doing things, but in the meantime that original x86 model has been improved to hold the VM semaphore for shorter times etc and to handle VM_FAULT_RETRY and other "newer" things, so it would be a good idea to bring all those improvements to the generic case and teach other architectures about them too. Reported-and-tested-by: Takashi Iwai <tiwai@suse.de> Tested-by: Jan Engelhardt <jengelh@inai.de> Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> # "s390 still compiles and boots" Cc: linux-arch@vger.kernel.org Cc: stable@vger.kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-01-13openrisc/uaccess: fix sparse errorsMichael S. Tsirkin
virtio wants to read bitwise types from userspace using get_user. At the moment this triggers sparse errors, since the value is passed through an integer. Fix that up using __force. Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-12-10net, lib: kill arch_fast_hash library bitsDaniel Borkmann
As there are now no remaining users of arch_fast_hash(), lets kill it entirely. This basically reverts commit 71ae8aac3e19 ("lib: introduce arch optimized hash library") and follow-up work, that is f.e., commit 237217546d44 ("lib: hash: follow-up fixups for arch hash"), commit e3fec2f74f7f ("lib: Add missing arch generic-y entries for asm-generic/hash.h") and last but not least commit 6a02652df511 ("perf tools: Fix include for non x86 architectures"). Cc: Francesco Fusco <fusco@ntop.org> Cc: Thomas Graf <tgraf@suug.ch> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-19Merge git://git.infradead.org/users/eparis/auditLinus Torvalds
Pull audit updates from Eric Paris: "So this change across a whole bunch of arches really solves one basic problem. We want to audit when seccomp is killing a process. seccomp hooks in before the audit syscall entry code. audit_syscall_entry took as an argument the arch of the given syscall. Since the arch is part of what makes a syscall number meaningful it's an important part of the record, but it isn't available when seccomp shoots the syscall... For most arch's we have a better way to get the arch (syscall_get_arch) So the solution was two fold: Implement syscall_get_arch() everywhere there is audit which didn't have it. Use syscall_get_arch() in the seccomp audit code. Having syscall_get_arch() everywhere meant it was a useless flag on the stack and we could get rid of it for the typical syscall entry. The other changes inside the audit system aren't grand, fixed some records that had invalid spaces. Better locking around the task comm field. Removing some dead functions and structs. Make some things static. Really minor stuff" * git://git.infradead.org/users/eparis/audit: (31 commits) audit: rename audit_log_remove_rule to disambiguate for trees audit: cull redundancy in audit_rule_change audit: WARN if audit_rule_change called illegally audit: put rule existence check in canonical order next: openrisc: Fix build audit: get comm using lock to avoid race in string printing audit: remove open_arg() function that is never used audit: correct AUDIT_GET_FEATURE return message type audit: set nlmsg_len for multicast messages. audit: use union for audit_field values since they are mutually exclusive audit: invalid op= values for rules audit: use atomic_t to simplify audit_serial() kernel/audit.c: use ARRAY_SIZE instead of sizeof/sizeof[0] audit: reduce scope of audit_log_fcaps audit: reduce scope of audit_net_id audit: arm64: Remove the audit arch argument to audit_syscall_entry arm64: audit: Add audit hook in syscall_trace_enter/exit() audit: x86: drop arch from __audit_syscall_entry() interface sparc: implement is_32bit_task sparc: properly conditionalize use of TIF_32BIT ...
2014-10-09Merge branch 'irq-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq updates from Thomas Gleixner: "The irq departement delivers: - a cleanup series to get rid of mindlessly copied code. - another bunch of new pointlessly different interrupt chip drivers. Adding homebrewn irq chips (and timers) to SoCs must provide a value add which is beyond the imagination of mere mortals. - the usual SoC irq controller updates, IOW my second cat herding project" * 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (44 commits) irqchip: gic-v3: Implement CPU PM notifier irqchip: gic-v3: Refactor gic_enable_redist to support both enabling and disabling irqchip: renesas-intc-irqpin: Add minimal runtime PM support irqchip: renesas-intc-irqpin: Add helper variable dev = &pdev->dev irqchip: atmel-aic5: Add sama5d4 support irqchip: atmel-aic5: The sama5d3 has 48 IRQs Documentation: bcm7120-l2: Add Broadcom BCM7120-style L2 binding irqchip: bcm7120-l2: Add Broadcom BCM7120-style Level 2 interrupt controller irqchip: renesas-irqc: Add binding docs for new R-Car Gen2 SoCs irqchip: renesas-irqc: Add DT binding documentation irqchip: renesas-intc-irqpin: Document SoC-specific bindings openrisc: Get rid of handle_IRQ arm64: Get rid of handle_IRQ ARM: omap2: irq: Convert to handle_domain_irq ARM: imx: tzic: Convert to handle_domain_irq ARM: imx: avic: Convert to handle_domain_irq irqchip: or1k-pic: Convert to handle_domain_irq irqchip: atmel-aic5: Convert to handle_domain_irq irqchip: atmel-aic: Convert to handle_domain_irq irqchip: gic-v3: Convert to handle_domain_irq ...
2014-09-26next: openrisc: Fix buildGuenter Roeck
openrisc:defconfig fails to build in next-20140926 with the following error. In file included from arch/openrisc/kernel/signal.c:31:0: ./arch/openrisc/include/asm/syscall.h: In function 'syscall_get_arch': ./arch/openrisc/include/asm/syscall.h:77:9: error: 'EM_OPENRISC' undeclared Fix by moving EM_OPENRISC to include/uapi/linux/elf-em.h. Fixes: ce5d112827e5 ("ARCH: AUDIT: implement syscall_get_arch for all arches") Cc: Eric Paris <eparis@redhat.com> Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Eric Paris <eparis@redhat.com>
2014-09-23ARCH: AUDIT: audit_syscall_entry() should not require the archEric Paris
We have a function where the arch can be queried, syscall_get_arch(). So rather than have every single piece of arch specific code use and/or duplicate syscall_get_arch(), just have the audit code use the syscall_get_arch() code. Based-on-patch-by: Richard Briggs <rgb@redhat.com> Signed-off-by: Eric Paris <eparis@redhat.com> Cc: linux-alpha@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-ia64@vger.kernel.org Cc: microblaze-uclinux@itee.uq.edu.au Cc: linux-mips@linux-mips.org Cc: linux@lists.openrisc.net Cc: linux-parisc@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-s390@vger.kernel.org Cc: linux-sh@vger.kernel.org Cc: sparclinux@vger.kernel.org Cc: user-mode-linux-devel@lists.sourceforge.net Cc: linux-xtensa@linux-xtensa.org Cc: x86@kernel.org
2014-09-23ARCH: AUDIT: implement syscall_get_arch for all archesEric Paris
For all arches which support audit implement syscall_get_arch() They are all pretty easy and straight forward, stolen from how the call to audit_syscall_entry() determines the arch. Based-on-patch-by: Richard Briggs <rgb@redhat.com> Signed-off-by: Eric Paris <eparis@redhat.com> Cc: linux-ia64@vger.kernel.org Cc: microblaze-uclinux@itee.uq.edu.au Cc: linux-mips@linux-mips.org Cc: linux@lists.openrisc.net Cc: linux-parisc@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: sparclinux@vger.kernel.org
2014-09-13irq_work: Introduce arch_irq_work_has_interrupt()Peter Zijlstra
The nohz full code needs irq work to trigger its own interrupt so that the subsystem can work even when the tick is stopped. Lets introduce arch_irq_work_has_interrupt() that archs can override to tell about their support for this ability. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2014-09-03openrisc: Get rid of handle_IRQMarc Zyngier
The openrisc irqchip driver has been converted to handle_domain_irq, making it possible to remove the handle_IRQ stub entierely. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Acked-by: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi> Link: https://lkml.kernel.org/r/1409047421-27649-27-git-send-email-marc.zyngier@arm.com Signed-off-by: Jason Cooper <jason@lakedaemon.net>
2014-09-03openrisc: Convert handle_IRQ to use __handle_domain_irqMarc Zyngier
In order to limit code duplication, convert the architecture specific handle_IRQ to use the generic __handle_domain_irq function. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Acked-by: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi> Link: https://lkml.kernel.org/r/1409047421-27649-5-git-send-email-marc.zyngier@arm.com Signed-off-by: Jason Cooper <jason@lakedaemon.net>
2014-08-09Merge branch 'signal-cleanup' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rw/misc Pull arch signal handling cleanup from Richard Weinberger: "This patch series moves all remaining archs to the get_signal(), signal_setup_done() and sigsp() functions. Currently these archs use open coded variants of the said functions. Further, unused parameters get removed from get_signal_to_deliver(), tracehook_signal_handler() and signal_delivered(). At the end of the day we save around 500 lines of code." * 'signal-cleanup' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/misc: (43 commits) powerpc: Use sigsp() openrisc: Use sigsp() mn10300: Use sigsp() mips: Use sigsp() microblaze: Use sigsp() metag: Use sigsp() m68k: Use sigsp() m32r: Use sigsp() hexagon: Use sigsp() frv: Use sigsp() cris: Use sigsp() c6x: Use sigsp() blackfin: Use sigsp() avr32: Use sigsp() arm64: Use sigsp() arc: Use sigsp() sas_ss_flags: Remove nested ternary if Rip out get_signal_to_deliver() Clean up signal_delivered() tracehook_signal_handler: Remove sig, info, ka and regs ...
2014-08-06openrisc: Use sigsp()Richard Weinberger
Use sigsp() instead of the open coded variant. Signed-off-by: Richard Weinberger <richard@nod.at>
2014-08-05Merge branch 'irq-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq updates from Thomas Gleixner: "Nothing spectacular from the irq department this time: - overhaul of the crossbar chip driver - overhaul of the spear shirq chip driver - support for the atmel-aic chip - code move from arch to drivers - the usual tiny fixlets - two reverts worth to mention which undo the too simple attempt of supporting wakeup interrupts on shared interrupt lines" * 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (41 commits) Revert "irq: Warn when shared interrupts do not match on NO_SUSPEND" Revert "PM / sleep / irq: Do not suspend wakeup interrupts" irq: Warn when shared interrupts do not match on NO_SUSPEND irqchip: atmel-aic: Define irq fixups for atmel SoCs irqchip: atmel-aic: Implement RTC irq fixup irqchip: atmel-aic: Add irq fixup infrastructure irqchip: atmel-aic: Add atmel AIC/AIC5 drivers irqchip: atmel-aic: Move binding doc to interrupt-controller directory genirq: generic chip: Export irq_map_generic_chip function PM / sleep / irq: Do not suspend wakeup interrupts irqchip: or1k-pic: Migrate from arch/openrisc/ irqchip: crossbar: Allow for quirky hardware with direct hardwiring of GIC documentation: dt: omap: crossbar: Add description for interrupt consumer irqchip: crossbar: Introduce centralized check for crossbar write irqchip: crossbar: Introduce ti, max-crossbar-sources to identify valid crossbar mapping irqchip: crossbar: Add kerneldoc for crossbar_domain_unmap callback irqchip: crossbar: Set cb pointer to null in case of error irqchip: crossbar: Change the goto naming irqchip: crossbar: Return proper error value irqchip: crossbar: Fix kerneldoc warning ...
2014-07-17arch, locking: Ciao arch_mutex_cpu_relax()Davidlohr Bueso
The arch_mutex_cpu_relax() function, introduced by 34b133f, is hacky and ugly. It was added a few years ago to address the fact that common cpu_relax() calls include yielding on s390, and thus impact the optimistic spinning functionality of mutexes. Nowadays we use this function well beyond mutexes: rwsem, qrwlock, mcs and lockref. Since the macro that defines the call is in the mutex header, any users must include mutex.h and the naming is misleading as well. This patch (i) renames the call to cpu_relax_lowlatency ("relax, but only if you can do it with very low latency") and (ii) defines it in each arch's asm/processor.h local header, just like for regular cpu_relax functions. On all archs, except s390, cpu_relax_lowlatency is simply cpu_relax, and thus we can take it out of mutex.h. While this can seem redundant, I believe it is a good choice as it allows us to move out arch specific logic from generic locking primitives and enables future(?) archs to transparently define it, similarly to System Z. Signed-off-by: Davidlohr Bueso <davidlohr@hp.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Anton Blanchard <anton@samba.org> Cc: Aurelien Jacquiot <a-jacquiot@ti.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Bharat Bhushan <r65777@freescale.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chen Liqin <liqin.linux@gmail.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Chris Zankel <chris@zankel.net> Cc: David Howells <dhowells@redhat.com> Cc: David S. Miller <davem@davemloft.net> Cc: Deepthi Dharwar <deepthi@linux.vnet.ibm.com> Cc: Dominik Dingel <dingel@linux.vnet.ibm.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Cc: Haavard Skinnemoen <hskinnemoen@gmail.com> Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Helge Deller <deller@gmx.de> Cc: Hirokazu Takata <takata@linux-m32r.org> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: James E.J. Bottomley <jejb@parisc-linux.org> Cc: James Hogan <james.hogan@imgtec.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Jesper Nilsson <jesper.nilsson@axis.com> Cc: Joe Perches <joe@perches.com> Cc: Jonas Bonn <jonas@southpole.se> Cc: Joseph Myers <joseph@codesourcery.com> Cc: Kees Cook <keescook@chromium.org> Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com> Cc: Lennox Wu <lennox.wu@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mark Salter <msalter@redhat.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Matt Turner <mattst88@gmail.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Neuling <mikey@neuling.org> Cc: Michal Simek <monstr@monstr.eu> Cc: Mikael Starvik <starvik@axis.com> Cc: Nicolas Pitre <nico@linaro.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Qais Yousef <qais.yousef@imgtec.com> Cc: Qiaowei Ren <qiaowei.ren@intel.com> Cc: Rafael Wysocki <rafael.j.wysocki@intel.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Richard Henderson <rth@twiddle.net> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Steven Miao <realmz6@gmail.com> Cc: Steven Rostedt <srostedt@redhat.com> Cc: Stratos Karafotis <stratosk@semaphore.gr> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Vasily Kulikov <segoon@openwall.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Vineet Gupta <Vineet.Gupta1@synopsys.com> Cc: Waiman Long <Waiman.Long@hp.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Wolfram Sang <wsa@the-dreams.de> Cc: adi-buildroot-devel@lists.sourceforge.net Cc: linux390@de.ibm.com Cc: linux-alpha@vger.kernel.org Cc: linux-am33-list@redhat.com Cc: linux-arm-kernel@lists.infradead.org Cc: linux-c6x-dev@linux-c6x.org Cc: linux-cris-kernel@axis.com Cc: linux-hexagon@vger.kernel.org Cc: linux-ia64@vger.kernel.org Cc: linux@lists.openrisc.net Cc: linux-m32r-ja@ml.linux-m32r.org Cc: linux-m32r@ml.linux-m32r.org Cc: linux-m68k@lists.linux-m68k.org Cc: linux-metag@vger.kernel.org Cc: linux-mips@linux-mips.org Cc: linux-parisc@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-s390@vger.kernel.org Cc: linux-sh@vger.kernel.org Cc: linux-xtensa@linux-xtensa.org Cc: sparclinux@vger.kernel.org Link: http://lkml.kernel.org/r/1404079773.2619.4.camel@buesod1.americas.hpqcorp.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-07-01irqchip: or1k-pic: Migrate from arch/openrisc/Stefan Kristiansson
In addition to consolidating the or1k-pic with other interrupt controllers, this makes OpenRISC less tied to its on-cpu interrupt controller. All or1k-pic specific parts are moved out of irq.c and into drivers/irqchip/irq-or1k-pic.c In that transition, the functionality have been divided into three chip variants. One that handles level triggered interrupts, one that handles edge triggered interrupts and one that handles the interrupt controller that is present in the or1200 OpenRISC cpu implementation. Signed-off-by: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi> Link: https://lkml.kernel.org/r/1401136302-27654-1-git-send-email-stefan.kristiansson@saunalahti.fi Acked-by: Jonas Bonn <jonas@southpole.se> Signed-off-by: Jason Cooper <jason@lakedaemon.net>
2014-06-04Merge tag 'devicetree-for-3.16' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux into next Pull DeviceTree updates from Rob Herring: - Another round of clean-up of FDT related code in architecture code. This removes knowledge of internal FDT details from most architectures except powerpc. - Conversion of kernel's custom FDT parsing code to use libfdt. - DT based initialization for generic serial earlycon. The introduction of generic serial earlycon support went in through the tty tree. - Improve the platform device naming for DT probed devices to ensure unique naming and use parent names instead of a global index. - Fix a race condition in of_update_property. - Unify the various linker section OF match tables and fix several function prototype errors. - Update platform_get_irq_byname to work in deferred probe cases. - 2 binding doc updates * tag 'devicetree-for-3.16' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (58 commits) of: handle NULL node in next_child iterators of/irq: provide more wrappers for !CONFIG_OF devicetree: bindings: Document micrel vendor prefix dt: bindings: dwc2: fix required value for the phy-names property of_pci_irq: kill useless variable in of_irq_parse_pci() of/irq: do irq resolution in platform_get_irq_byname() of: Add a testcase for of_find_node_by_path() of: Make of_find_node_by_path() handle /aliases of: Create unlocked version of for_each_child_of_node() lib: add glibc style strchrnul() variant of: Handle memory@0 node on PPC32 only pci/of: Remove dead code of: fix race between search and remove in of_update_property() of: Use NULL for pointers of: Stop naming platform_device using dcr address of: Ensure unique names without sacrificing determinism tty/serial: pl011: add DT based earlycon support of/fdt: add FDT serial scanning for earlycon of/fdt: add FDT address translation support serial: earlycon: add DT support ...
2014-04-30of/fdt: consolidate built-in dtb section variablesRob Herring
Unify the various architectures __dtb_start and __dtb_end definitions moving them into of_fdt.h. Signed-off-by: Rob Herring <robh@kernel.org> Acked-by: Vineet Gupta <vgupta@synopsys.com> Acked-by: James Hogan <james.hogan@imgtec.com> Tested-by: Michal Simek <michal.simek@xilinx.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Jonas Bonn <jonas@southpole.se> Cc: Chris Zankel <chris@zankel.net> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: linux-metag@vger.kernel.org Cc: linux-mips@linux-mips.org Cc: linux@lists.openrisc.net Cc: linux-xtensa@linux-xtensa.org Tested-by: Grant Likely <grant.likely@linaro.org> Tested-by: Stephen Chivers <schivers@csc.com>
2014-04-18arch,openrisc: Convert smp_mb__*()Peter Zijlstra
Openrisc fully relies on asm-generic/barrier.h and therefore its smp_mb() is barrier(). Signed-off-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Link: http://lkml.kernel.org/n/tip-sxgxgqag9tond4kji07d22oh@git.kernel.org Cc: Jonas Bonn <jonas@southpole.se> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: linux-kernel@vger.kernel.org Cc: linux@lists.openrisc.net Signed-off-by: Ingo Molnar <mingo@kernel.org>