- 08 Aug, 2014 40 commits
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Fabian Frederick authored
Warns or generates patch for NULL check before the following functions: kfree usb_free_urb debugfs_remove debugfs_remove_recursive Signed-off-by: Fabian Frederick <fabf@skynet.be> Acked-by: Julia Lawall <Julia.Lawall@lip6.fr> Cc: Gilles Muller <Gilles.Muller@lip6.fr> Cc: Joe Perches <joe@perches.com> Cc: Markus Elfring <elfring@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Laura Abbott authored
There's no need to have an architecture version of scatterlist.h if the only thing the file does is include asm-generic/scatterlist.h. Switch to the asm-generic versions directly. Acked-by: Jesper Nilsson <jesper.nilsson@axis.com> Acked-by: David Howells <dhowells@redhat.com> Signed-off-by: Laura Abbott <lauraa@codeaurora.org> Cc: Lennox Wu <lennox.wu@gmail.com> Cc: Chen Liqin <liqin.linux@gmail.com>, Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com> Cc: Michal Simek <monstr@monstr.eu> Cc: Hirokazu Takata <takata@linux-m32r.org> Cc: Mikael Starvik <starvik@axis.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Tony Luck <tony.luck@intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: "James E.J. Bottomley" <JBottomley@parallels.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Laura Abbott authored
Rather than have architectures #define ARCH_HAS_SG_CHAIN in an architecture specific scatterlist.h, make it a proper Kconfig option and use that instead. At same time, remove the header files are are now mostly useless and just include asm-generic/scatterlist.h. [sfr@canb.auug.org.au: powerpc files now need asm/dma.h] Signed-off-by: Laura Abbott <lauraa@codeaurora.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> [x86] Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> [powerpc] Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Tony Luck <tony.luck@intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: "James E.J. Bottomley" <JBottomley@parallels.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Jack Miller authored
A small cleanup while changing adjacent code. Extern is not needed for functions and only one declaration had it so remove it from the odd line. Signed-off-by: Milton Miller <miltonm@bga.com> Signed-off-by: Jack Miller <millerjo@us.ibm.com> Cc: Davidlohr Bueso <davidlohr@hp.com> Cc: Manfred Spraul <manfred@colorfullife.com> Cc: Anton Blanchard <anton@samba.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Jack Miller authored
If shm_rmid_force (the default state) is not set then the shmids are only marked as orphaned and does not require any add, delete, or locking of the tree structure. Seperate the sysctl on and off case, and only obtain the read lock. The newly added list head can be deleted under the read lock because we are only called with current and will only change the semids allocated by this task and not manipulate the list. This commit assumes that up_read includes a sufficient memory barrier for the writes to be seen my others that later obtain a write lock. Signed-off-by: Milton Miller <miltonm@bga.com> Signed-off-by: Jack Miller <millerjo@us.ibm.com> Cc: Davidlohr Bueso <davidlohr@hp.com> Cc: Manfred Spraul <manfred@colorfullife.com> Cc: Anton Blanchard <anton@samba.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Jack Miller authored
This is small set of patches our team has had kicking around for a few versions internally that fixes tasks getting hung on shm_exit when there are many threads hammering it at once. Anton wrote a simple test to cause the issue: http://ozlabs.org/~anton/junkcode/bust_shm_exit.c Before applying this patchset, this test code will cause either hanging tracebacks or pthread out of memory errors. After this patchset, it will still produce output like: root@somehost:~# ./bust_shm_exit 1024 160 ... INFO: rcu_sched detected stalls on CPUs/tasks: {} (detected by 116, t=2111 jiffies, g=241, c=240, q=7113) INFO: Stall ended before state dump start ... But the task will continue to run along happily, so we consider this an improvement over hanging, even if it's a bit noisy. This patch (of 3): exit_shm obtains the ipc_ns shm rwsem for write and holds it while it walks every shared memory segment in the namespace. Thus the amount of work is related to the number of shm segments in the namespace not the number of segments that might need to be cleaned. In addition, this occurs after the task has been notified the thread has exited, so the number of tasks waiting for the ns shm rwsem can grow without bound until memory is exausted. Add a list to the task struct of all shmids allocated by this task. Init the list head in copy_process. Use the ns->rwsem for locking. Add segments after id is added, remove before removing from id. On unshare of NEW_IPCNS orphan any ids as if the task had exited, similar to handling of semaphore undo. I chose a define for the init sequence since its a simple list init, otherwise it would require a function call to avoid include loops between the semaphore code and the task struct. Converting the list_del to list_del_init for the unshare cases would remove the exit followed by init, but I left it blow up if not inited. Signed-off-by: Milton Miller <miltonm@bga.com> Signed-off-by: Jack Miller <millerjo@us.ibm.com> Cc: Davidlohr Bueso <davidlohr@hp.com> Cc: Manfred Spraul <manfred@colorfullife.com> Cc: Anton Blanchard <anton@samba.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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David Engraf authored
On a system with low memory extracting the initramfs may fail. If this happens the user gets "Failed to execute /init" instead of an initramfs error. Check return value of sys_write and call error() when the write was incomplete or failed. Signed-off-by: David Engraf <david.engraf@sysgo.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Yinghai Lu authored
Now with 64bit bzImage and kexec tools, we support ramdisk that size is bigger than 2g, as we could put it above 4G. Found compressed initramfs image could not be decompressed properly. It turns out that image length is int during decompress detection, and it will become < 0 when length is more than 2G. Furthermore, during decompressing len as int is used for inbuf count, that has problem too. Change len to long, that should be ok as on 32 bit platform long is 32bits. Tested with following compressed initramfs image as root with kexec. gzip, bzip2, xz, lzma, lzop, lz4. run time for populate_rootfs(): size name Nehalem-EX Westmere-EX Ivybridge-EX 9034400256 root_img : 26s 24s 30s 3561095057 root_img.lz4 : 28s 27s 27s 3459554629 root_img.lzo : 29s 29s 28s 3219399480 root_img.gz : 64s 62s 49s 2251594592 root_img.xz : 262s 260s 183s 2226366598 root_img.lzma: 386s 376s 277s 2901482513 root_img.bz2 : 635s 599s Signed-off-by: Yinghai Lu <yinghai@kernel.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Rashika Kheria <rashika.kheria@gmail.com> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Kyungsik Lee <kyungsik.lee@lge.com> Cc: P J P <ppandit@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> Cc: "Daniel M. Weeks" <dan@danweeks.net> Cc: Alexandre Courbot <acourbot@nvidia.com> Cc: Jan Beulich <JBeulich@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Yinghai Lu authored
When initrd (compressed or not) is used, kernel report data corrupted with /dev/ram0. The root cause: During initramfs checking, if it is initrd, it will be transferred to /initrd.image with sys_write. sys_write only support 2G-4K write, so if the initrd ram is more than that, /initrd.image will not complete at all. Add local xwrite to loop calling sys_write to workaround the problem. Also need to use xwrite in write_buffer() to handle: image is uncompressed cpio and there is one big file (>2G) in it. unpack_to_rootfs ===> write_buffer ===> actions[]/do_copy At the same time, we don't need to worry about sys_read/sys_write in do_mounts_rd.c::crd_load. As decompressor will have fill/flush and local buffer that is smaller than 2G. Test with uncompressed initrd, and compressed ones with gz, bz2, lzma,xz, lzop. Signed-off-by: Yinghai Lu <yinghai@kernel.org> Acked-by: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> Cc: "Daniel M. Weeks" <dan@danweeks.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Yinghai Lu authored
During testing initrd (>2G) support, find decompress/lz4 does not work with initrd at all. decompress_* should support: 1. inbuf[]/outbuf[] for kernel preboot. 2. inbuf[]/flush() for initramfs 3. fill()/flush() for initrd. in the unlz4 does not handle case 3, as input len is passed as 0, and it failed in first try. Fix that add one extra if (fill) checking, and get out if EOF from the fill(). Signed-off-by: Yinghai Lu <yinghai@kernel.org> Cc: Kyungsik Lee <kyungsik.lee@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Fabian Frederick authored
Add DDEBUG in Makefile when CONFIG_QNX6FS_DEBUG is set. All QNX6DEBUG messages are replaced by pr_debug which means debugging will be emitted in debug level only and no more in error and info levels. debug uses now pr_fmt and __func__ QNX6DEBUG definition has been removed. Signed-off-by: Fabian Frederick <fabf@skynet.be> Cc: Joe Perches <joe@perches.com> Cc: Kai Bankett <chaosman@ontika.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Fabian Frederick authored
Remove "qnx6:" and "qnx6: " from each logging instruction. Signed-off-by: Fabian Frederick <fabf@skynet.be> Cc: Joe Perches <joe@perches.com> Cc: Kai Bankett <chaosman@ontika.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Fabian Frederick authored
Use current logging functions. Coalesce formats. Signed-off-by: Fabian Frederick <fabf@skynet.be> Cc: Joe Perches <joe@perches.com> Cc: Kai Bankett <chaosman@ontika.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Fabian Frederick authored
Fix checkpatch warning: WARNING: Missing a blank line after declarations Signed-off-by: Fabian Frederick <fabf@skynet.be> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Fabian Frederick authored
- Remove "Error" in format logging (already in pr_ level) - Use modulename in pr_fmt instead of ROMFS: in each pr_ callsites. Signed-off-by: Fabian Frederick <fabf@skynet.be> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Fabian Frederick authored
Use current logging functions. Coalesce formats. Signed-off-by: Fabian Frederick <fabf@skynet.be> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Fabian Frederick authored
Fixes checkpatch warning: WARNING: Use #include <linux/uaccess.h> instead of <asm/uaccess.h> Signed-off-by: Fabian Frederick <fabf@skynet.be> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Fabian Frederick authored
Fixes some checkpatch errors/warnings: WARNING: Missing a blank line after declarations ERROR: spaces required around that '=' (ctx:VxV) ERROR: "foo * bar" should be "foo *bar" ERROR: space prohibited after that open parenthesis '(' Signed-off-by: Fabian Frederick <fabf@skynet.be> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Fabian Frederick authored
Use module name for "cramfs: " prefix. (note that uncompress.c printk had no prefix). Signed-off-by: Fabian Frederick <fabf@skynet.be> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Fabian Frederick authored
Use current logging functions. No level printk converted to pr_err Signed-off-by: Fabian Frederick <fabf@skynet.be> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Thierry Fauck authored
On IBM powerpc where multiple page size value are supported, current ppc64 and ppc64el distro don't define the PAGE_SIZE variable in /usr/include as this is a dynamic value retrieved by the getpagesize() or sysconf() defined in unistd.h. The PAGE_SIZE variable sounds defined when only one value is supported by the kernel. As such, when the PAGE_SIZE definition doesn't exist system should retrieve the dynamic value. Signed-off-by: Thierry Fauck <thierry@linux.vnet.ibm.com> Cc: Andrey Vagin <avagin@openvz.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Himangi Saraogi authored
Use BUG_ON(x) rather than if(x) BUG(); The semantic patch that fixes this problem is as follows: // <smpl> @@ identifier x; @@ -if (!x) BUG(); +BUG_ON(!x); // </smpl> Signed-off-by: Himangi Saraogi <himangi774@gmail.com> Acked-by: Julia Lawall <julia.lawall@lip6.fr> Cc: Stefani Seibold <stefani@seibold.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Fabian Frederick authored
kcalloc manages count*sizeof overflow. Signed-off-by: Fabian Frederick <fabf@skynet.be> Acked-by: Bob Copeland <me@bobcopeland.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Fabian Frederick authored
kmalloc_array manages count*sizeof overflow. Signed-off-by: Fabian Frederick <fabf@skynet.be> Cc: Anton Vorontsov <anton@enomsg.org> Cc: Colin Cross <ccross@android.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Fabian Frederick authored
replace IS_ERR/PTR_ERR Signed-off-by: Fabian Frederick <fabf@skynet.be> Cc: Wolfram Sang <wsa@the-dreams.de> Cc: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Josh Hunt authored
This taint flag will be set if the system has ever entered a softlockup state. Similar to TAINT_WARN it is useful to know whether or not the system has been in a softlockup state when debugging. [akpm@linux-foundation.org: apply the taint before calling panic()] Signed-off-by: Josh Hunt <johunt@akamai.com> Cc: Jason Baron <jbaron@akamai.com> Cc: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Fabian Frederick authored
All bfs related functions use bfs_ prefix. This patch also moves extern declaration to bfs.h and removes prototype from inode.c This fixes checkpatch warning: WARNING: externs should be avoided in .c files Signed-off-by: Fabian Frederick <fabf@skynet.be> Cc: "Tigran A. Aivazian" <tigran@aivazian.fsnet.co.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Joe Perches authored
Might as well do the right thing. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Fabian Frederick authored
kcalloc manages count*sizeof overflow. Signed-off-by: Fabian Frederick <fabf@skynet.be> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Fabian Frederick authored
Use kernel.h definition. Signed-off-by: Fabian Frederick <fabf@skynet.be> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Fabian Frederick authored
This fixes checkpatch warning: WARNING: debugfs_remove(NULL) is safe this check is probably not required Signed-off-by: Fabian Frederick <fabf@skynet.be> Cc: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Fabian Frederick authored
kcalloc manages count*sizeof overflow. Signed-off-by: Fabian Frederick <fabf@skynet.be> Acked-by: Boaz Harrosh <bharrosh@panasas.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Joe Perches authored
Remove the final user, and the typedef itself. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Wei Yang authored
In case 1, it passes down the BLACK color from G to p and u, and maintains the color of n. By doing so, it maintains the black height of the sub-tree. While in the comment, it marks the color of n to BLACK. This is a typo and not consistents with the code. This patch fixs this typo in comment. Signed-off-by: Wei Yang <weiyang@linux.vnet.ibm.com> Acked-by: Michel Lespinasse <walken@google.com> Cc: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Alexandre Bounine authored
Rework Tsi721 RapidIO DMA engine support to allow handling data scatter/gather lists longer than number of hardware buffer descriptors in the DMA channel's descriptor list. The current implementation of Tsi721 DMA transfers requires that number of entries in a scatter/gather list provided by a caller of dmaengine_prep_rio_sg() should not exceed number of allocated hardware buffer descriptors. This patch removes the limitation by processing long scatter/gather lists by sections that can be transferred using hardware descriptor ring of configured size. It also introduces a module parameter "dma_desc_per_channel" to allow run-time configuration of Tsi721 hardware buffer descriptor rings. Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com> Cc: Matt Porter <mporter@kernel.crashing.org> Cc: Andre van Herk <andre.van.herk@prodrive-technologies.com> Cc: Stef van Os <stef.van.os@prodrive-technologies.com> Cc: Vinod Koul <vinod.koul@intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Alexandre Bounine authored
Add RapidIO DMA interface routines that directly use reference to the mport device object and/or target device destination ID as parameters. This allows to perform RapidIO DMA transfer requests by modules that do not have an access to the RapidIO device list. Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com> Cc: Matt Porter <mporter@kernel.crashing.org> Cc: Andre van Herk <andre.van.herk@prodrive-technologies.com> Cc: Stef van Os <stef.van.os@prodrive-technologies.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Andrey Ryabinin authored
I'm working on address sanitizer project for kernel. Recently we started experiments with stack instrumentation, to detect out-of-bounds read/write bugs on stack. Just after booting I've hit out-of-bounds read on stack in idr_for_each (and in __idr_remove_all as well): struct idr_layer **paa = &pa[0]; while (id >= 0 && id <= max) { ... while (n < fls(id)) { n += IDR_BITS; p = *--paa; <--- here we are reading pa[-1] value. } } Despite the fact that after this dereference we are exiting out of loop and never use p, such behaviour is undefined and should be avoided. Fix this by moving pointer derference to the beggining of the loop, right before we will use it. Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com> Reviewed-by: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Tejun Heo <tj@kernel.org> Cc: Alexey Preobrazhensky <preobr@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Konstantin Khlebnikov <koct9i@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Vitaly Kuznetsov authored
We have a special check in read_vmcore() handler to check if the page was reported as ram or not by the hypervisor (pfn_is_ram()). However, when vmcore is read with mmap() no such check is performed. That can lead to unpredictable results, e.g. when running Xen PVHVM guest memcpy() after mmap() on /proc/vmcore will hang processing HVMMEM_mmio_dm pages creating enormous load in both DomU and Dom0. Fix the issue by mapping each non-ram page to the zero page. Keep direct path with remap_oldmem_pfn_range() to avoid looping through all pages on bare metal. The issue can also be solved by overriding remap_oldmem_pfn_range() in xen-specific code, as remap_oldmem_pfn_range() was been designed for. That, however, would involve non-obvious xen code path for all x86 builds with CONFIG_XEN_PVHVM=y and would prevent all other hypervisor-specific code on x86 arch from doing the same override. [fengguang.wu@intel.com: remap_oldmem_pfn_checked() can be static] [akpm@linux-foundation.org: clean up layout] Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: Andrew Jones <drjones@redhat.com> Cc: Michael Holzheu <holzheu@linux.vnet.ibm.com> Acked-by: Vivek Goyal <vgoyal@redhat.com> Cc: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Vladimir Davydov authored
It's only used in fork.c:mm_init(). Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Vladimir Davydov authored
If a forking process has a thread calling (un)mmap (silly but still), the child process may have some of its mm's vm usage counters (total_vm and friends) screwed up, because currently they are copied from oldmm w/o holding any locks (memcpy in dup_mm). This patch moves the counters initialization to dup_mmap() to be called under oldmm->mmap_sem, which eliminates any possibility of race. Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: David Rientjes <rientjes@google.com> Cc: Christoph Lameter <cl@linux.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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