- 06 Jan, 2009 40 commits
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Harvey Harrison authored
Suppresses sparse warning: lib/proportions.c:159:16: warning: context imbalance in 'prop_get_global': wrong count at exit lib/proportions.c:159:16: context 'RCU': wanted 0, got 1 lib/proportions.c:164:2: warning: context imbalance in 'prop_put_global': unexpected unlock lib/proportions.c:164:2: context 'RCU': wanted 0, got -1 Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Harvey Harrison authored
radix_tree_preloads is unused outside of this file, make it static. Noticed by sparse: lib/radix-tree.c:84:1: warning: symbol 'per_cpu__radix_tree_preloads' was not declared. Should it be static? Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Harvey Harrison authored
pos is always set before being used, no need to declare a second one inside the if() block. lib/prio_heap.c:34:7: warning: symbol 'pos' shadows an earlier one lib/prio_heap.c:30:6: originally declared here Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Zhaolei authored
Check CLONE_SIGHAND only is enough, because combination of CLONE_THREAD and CLONE_SIGHAND is already done in copy_process(). Impact: cleanup, no functionality changed Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com> Cc: Roland McGrath <roland@redhat.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>
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Alexey Dobriyan authored
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: Gabor Gombas <gombasg@sztaki.hu> Cc: Jan Beulich <jbeulich@novell.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Ingo Molnar <mingo@elte.hu>, Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Luiz Fernando N. Capitulino authored
Untangle the error unwinding in this function, saving a test of local variable `vma'. Signed-off-by: Luiz Fernando N. Capitulino <lcapitulino@mandriva.com.br> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Marton Balint authored
In the past, I used the root=... command line parameter to specify the root filesystem to the kernel. Now it seems that specifying it is not necessary. The kernel detects the root filesystem even if the kernel command line is empty. My root fs is on a raid1 device by the way, and I am not using initrd for the boot process. If the kernel detects the root filesystem somehow, I think it should print out the result of this detection, otherwise I will not know which device has the root filesystem. Or is there an easy way to get this information on a running system? I had a quick look at the /proc and /sys filesystems, but haven't found anything useful there. Signed-off-by: Marton Balint <cus@fazekas.hu> Cc: Christoph Hellwig <hch@lst.de> 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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Viktor Rosendahl authored
This used to work unpatched with older kernels, during the development phase of mtdoops. Before commit e3e8a75d a space was printed with console_loglevel set to 15, which probably flushed the oops message as a side effect. This is another patch from the Nokia N810 kernel. Signed-off-by: Viktor Rosendahl <viktor.rosendahl@nokia.com> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Ingo Molnar <mingo@elte.hu> Cc: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Laurent Pinchart authored
Several subsystem open handlers dereference the fops_get() return value without checking it for nullness. This opens a race condition between the open handler and module unloading. A module can be marked as being unloaded (MODULE_STATE_GOING) before its exit function is called and gets the chance to unregister the driver. During that window open handlers can still be called, and fops_get() will fail in try_module_get() and return a NULL pointer. This change checks the fops_get() return value and returns -ENODEV if NULL. Reported-by: Alan Jenkins <alan-jenkins@tuffmail.co.uk> Signed-off-by: Laurent Pinchart <laurent.pinchart@skynet.be> Acked-by: Takashi Iwai <tiwai@suse.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Dave Airlie <airlied@linux.ie> Acked-by: Mauro Carvalho Chehab <mchehab@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Arjan van de Ven authored
Use the newly introduced pci_ioremap_bar() function in drivers/misc. pci_ioremap_bar() just takes a pci device and a bar number, with the goal of making it really hard to get wrong, while also having a central place to stick sanity checks. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Matthew Wilcox authored
The atomic_t type cannot currently be used in some header files because it would create an include loop with asm/atomic.h. Move the type definition to linux/types.h to break the loop. Signed-off-by: Matthew Wilcox <willy@linux.intel.com> Cc: Huang Ying <ying.huang@intel.com> Cc: <linux-arch@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Rakib Mullick authored
checkpatch warns about 'static void noinline'. It wants `static noinline void'. Both are permissible, but the kernel consistently uses `static inline' and `static noinline', and consistency is good. Hence let's keep the checkpatch warning and fix up this code site. [akpm@linux-foundation.org: rewrote changelog] Signed-off-by: Md.Rakib H. Mullick <rakib.mullick@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Cyrill Gorcunov authored
At this point we already know that 'addr' is not NULL so get rid of redundant 'if'. Probably gcc eliminate it by optimization pass. [akpm@linux-foundation.org: use __weak, too] Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> Reviewed-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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KOSAKI Motohiro authored
Wassim Dagash reported following kswapd infinite loop problem. kswapd runs in some infinite loop trying to swap until order 10 of zone highmem is OK.... kswapd will continue to try to balance order 10 of zone highmem forever (or until someone release a very large chunk of highmem). For non order-0 allocations, the system may never be balanced due to fragmentation but kswapd should not infinitely loop as a result. Instead, recheck all watermarks at order-0 as they are the most important. If watermarks are ok, kswapd will go back to sleep. [akpm@linux-foundation.org: fix comment] Reported-by: wassim dagash <wassim.dagash@gmail.com> Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Reviewed-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Mel Gorman <mel@csn.ul.ie> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Johannes Weiner authored
Moving the request details print-out before the sanity checks that might panic() enables us to analyse invalid requests without having access to the line information of the stack dump. Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Johannes Weiner authored
When dup_mmap() ooms we can end up with mm->mmap == NULL. The error path does mmput() and unmap_vmas() gets a NULL vma which it dereferences. In exit_mmap() there is nothing to do at all for this case, we can cancel the callpath right there. [akpm@linux-foundation.org: add sorely-needed comment] Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Reported-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Cc: Hugh Dickins <hugh@veritas.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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KOSAKI Motohiro authored
page_queue_congested() was introduced in 2002, but it was never used Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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KOSAKI Motohiro authored
No architectures use CONFIG_OUT_OF_LINE_PFN_TO_PAGE - it can be removed. Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Oleg Nesterov authored
xacct_add_tsk() relies on do_exit()->update_hiwater_xxx() and uses mm->hiwater_xxx directly, this leads to 2 problems: - taskstats_user_cmd() can call fill_pid()->xacct_add_tsk() at any moment before the task exits, so we should check the current values of rss/vm anyway. - do_exit()->update_hiwater_xxx() calls are racy. An exiting thread can be preempted right before mm->hiwater_xxx = new_val, and another thread can use A_LOT of memory and exit in between. When the first thread resumes it can be the last thread in the thread group, in that case we report the wrong hiwater_xxx values which do not take A_LOT into account. Introduce get_mm_hiwater_rss() and get_mm_hiwater_vm() helpers and change xacct_add_tsk() to use them. The first helper will also be used by rusage->ru_maxrss accounting. Kill do_exit()->update_hiwater_xxx() calls. Unless we are going to decrease rss/vm there is no point to update mm->hiwater_xxx, and nobody can look at this mm_struct when exit_mmap() actually unmaps the memory. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Hugh Dickins <hugh@veritas.com> Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Acked-by: Balbir Singh <balbir@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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Nick Piggin authored
Frustratingly, gfp_t is really divided into two classes of flags. One are the context dependent ones (can we sleep? can we enter filesystem? block subsystem? should we use some extra reserves, etc.). The other ones are the type of memory required and depend on how the algorithm is implemented rather than the point at which the memory is allocated (highmem? dma memory? etc). Some of the functions which allocate a page and add it to page cache take a gfp_t, but sometimes those functions or their callers aren't really doing the right thing: when allocating pagecache page, the memory type should be mapping_gfp_mask(mapping). When allocating radix tree nodes, the memory type should be kernel mapped (not highmem) memory. The gfp_t argument should only really be needed for context dependent options. This patch doesn't really solve that tangle in a nice way, but it does attempt to fix a couple of bugs. - find_or_create_page changes its radix-tree allocation to only include the main context dependent flags in order so the pagecache page may be allocated from arbitrary types of memory without affecting the radix-tree. In practice, slab allocations don't come from highmem anyway, and radix-tree only uses slab allocations. So there isn't a practical change (unless some fs uses GFP_DMA for pages). - grab_cache_page_nowait() is changed to allocate radix-tree nodes with GFP_NOFS, because it is not supposed to reenter the filesystem. This bug could cause lock recursion if a filesystem is not expecting the function to reenter the fs (as-per documentation). Filesystems should be careful about exactly what semantics they want and what they get when fiddling with gfp_t masks to allocate pagecache. One should be as liberal as possible with the type of memory that can be used, and same for the the context specific flags. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Nick Piggin authored
s_syncing livelock avoidance was breaking data integrity guarantee of sys_sync, by allowing sys_sync to skip writing or waiting for superblocks if there is a concurrent sys_sync happening. This livelock avoidance is much less important now that we don't have the get_super_to_sync() call after every sb that we sync. This was replaced by __put_super_and_need_restart. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Nick Piggin authored
Fix data integrity semantics required by sys_sync, by iterating over all inodes and waiting for any writeback pages after the initial writeout. Comments explain the exact problem. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Nick Piggin authored
Remove WB_SYNC_HOLD. The primary motiviation is the design of my anti-starvation code for fsync. It requires taking an inode lock over the sync operation, so we could run into lock ordering problems with multiple inodes. It is possible to take a single global lock to solve the ordering problem, but then that would prevent a future nice implementation of "sync multiple inodes" based on lock order via inode address. Seems like a backward step to remove this, but actually it is busted anyway: we can't use the inode lists for data integrity wait: an inode can be taken off the dirty lists but still be under writeback. In order to satisfy data integrity semantics, we should wait for it to finish writeback, but if we only search the dirty lists, we'll miss it. It would be possible to have a "writeback" list, for sys_sync, I suppose. But why complicate things by prematurely optimise? For unmounting, we could avoid the "livelock avoidance" code, which would be easier, but again premature IMO. Fixing the existing data integrity problem will come next. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Artem Bityutskiy authored
WB_SYNC_HOLD is going to be zapped so we should not use it. Use %WB_SYNC_NONE instead. Here is what akpm said: "I think I'll just switch that to WB_SYNC_NONE. The `wait==0' mode is just an advisory thing to help the fs shove lots of data into the queues. If some gets missed then it'll be picked up on the second ->sync_fs call, with wait==1." Thanks to Randy Dunlap for catching this. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com> Cc: Nick Piggin <npiggin@suse.de> Cc: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Nick Piggin authored
Direct IO can invalidate and sync a lot of pagecache pages in the mapping. A 4K direct IO will actually try to sync and/or invalidate the pagecache of the entire file, for example (which might be many GB or TB large). Improve this by doing range syncs. Also, memory no longer has to be unmapped to catch the dirty bits for syncing, as dirty bits would remain coherent due to dirty mmap accounting. This fixes the immediate DM deadlocks when doing direct IO reads to block device with a mounted filesystem, if only by papering over the problem somewhat rather than addressing the fsync starvation cases. Signed-off-by: Nick Piggin <npiggin@suse.de> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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ZhenwenXu authored
Fix a little of the coding style in mm/mmap.c [akpm@linux-foundation.org: cleanup] Signed-off-by: ZhenwenXu <helight.xu@gmail.com> Signed-off-by: Hugh Dickins <hugh@veritas.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Matt Mackall authored
tiny-shmem shares most of its 130 lines of code with shmem and tends to break when particular bits of shmem get modified. Unifying saves code and makes keeping these two in sync much easier. before: 14367 392 24 14783 39bf mm/shmem.o 396 72 8 476 1dc mm/tiny-shmem.o after: 14367 392 24 14783 39bf mm/shmem.o 412 72 8 492 1ec mm/shmem.o tiny Signed-off-by: Matt Mackall <mpm@selenic.com> Acked-by: Hugh Dickins <hugh@veritas.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Franck Bui-Huu authored
Signed-off-by: Franck Bui-Huu <fbuihuu@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Ying Han authored
The initial implementation of checking TIF_MEMDIE covers the cases of OOM killing. If the process has been OOM killed, the TIF_MEMDIE is set and it return immediately. This patch includes: 1. add the case that the SIGKILL is sent by user processes. The process can try to get_user_pages() unlimited memory even if a user process has sent a SIGKILL to it(maybe a monitor find the process exceed its memory limit and try to kill it). In the old implementation, the SIGKILL won't be handled until the get_user_pages() returns. 2. change the return value to be ERESTARTSYS. It makes no sense to return ENOMEM if the get_user_pages returned by getting a SIGKILL signal. Considering the general convention for a system call interrupted by a signal is ERESTARTNOSYS, so the current return value is consistant to that. Lee: An unfortunate side effect of "make-get_user_pages-interruptible" is that it prevents a SIGKILL'd task from munlock-ing pages that it had mlocked, resulting in freeing of mlocked pages. Freeing of mlocked pages, in itself, is not so bad. We just count them now--altho' I had hoped to remove this stat and add PG_MLOCKED to the free pages flags check. However, consider pages in shared libraries mapped by more than one task that a task mlocked--e.g., via mlockall(). If the task that mlocked the pages exits via SIGKILL, these pages would be left mlocked and unevictable. Proposed fix: Add another GUP flag to ignore sigkill when calling get_user_pages from munlock()--similar to Kosaki Motohiro's 'IGNORE_VMA_PERMISSIONS flag for the same purpose. We are not actually allocating memory in this case, which "make-get_user_pages-interruptible" intends to avoid. We're just munlocking pages that are already resident and mapped, and we're reusing get_user_pages() to access those pages. ?? Maybe we should combine 'IGNORE_VMA_PERMISSIONS and '_IGNORE_SIGKILL into a single flag: GUP_FLAGS_MUNLOCK ??? [Lee.Schermerhorn@hp.com: ignore sigkill in get_user_pages during munlock] Signed-off-by: Paul Menage <menage@google.com> Signed-off-by: Ying Han <yinghan@google.com> Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Reviewed-by: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Cc: Hugh Dickins <hugh@veritas.com> Cc: Oleg Nesterov <oleg@tv-sign.ru> Cc: Lee Schermerhorn <lee.schermerhorn@hp.com> Cc: Rohit Seth <rohitseth@google.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Roel Kluin authored
unsigned long ret cannot be negative, but ret can get -EFAULT. Signed-off-by: Roel Kluin <roel.kluin@gmail.com> Cc: Hugh Dickins <hugh@veritas.com> Cc: Christoph Lameter <clameter@sgi.com> Cc: Adam Litke <agl@us.ibm.com> Cc: David Gibson <david@gibson.dropbear.id.au> Cc: Ken Chen <kenchen@google.com> Cc: Nick Piggin <npiggin@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Andrew Morton authored
These three statements manipulate local variables and do not need the lock coverage. Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com> Cc: Rik van Riel <riel@redhat.com Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Hugh Dickins authored
bad_page() and rmap Eeek messages have said KERN_EMERG for a few years, which I've followed in print_bad_pte(). These are serious system errors, on a par with BUGs, but they're not quite emergencies, and we do our best to carry on: say KERN_ALERT "BUG: " like the x86 oops does. And remove the "Trying to fix it up, but a reboot is needed" line: it's not untrue, but I hope the KERN_ALERT "BUG: " conveys as much. Signed-off-by: Hugh Dickins <hugh@veritas.com> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Cc: Christoph Lameter <cl@linux-foundation.org> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Hugh Dickins authored
print_bad_pte() and bad_page() might each need ratelimiting - especially for their dump_stacks, almost never of interest, yet not quite dispensible. Correlating corruption across neighbouring entries can be very helpful, so allow a burst of 60 reports before keeping quiet for the remainder of that minute (or allow a steady drip of one report per second). Signed-off-by: Hugh Dickins <hugh@veritas.com> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Cc: Christoph Lameter <cl@linux-foundation.org> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Hugh Dickins authored
Remove page_remove_rmap()'s vma arg, which was only for the Eeek message. And remove the BUG_ON(page_mapcount(page) == 0) from CONFIG_DEBUG_VM's page_dup_rmap(): we're trying to be more resilient about that than BUGs. Signed-off-by: Hugh Dickins <hugh@veritas.com> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Cc: Christoph Lameter <cl@linux-foundation.org> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Hugh Dickins authored
Complete zap_pte_range()'s coverage of bad pagetable entries by calling print_bad_pte() on a pte_file in a linear vma and on a bad swap entry. That needs free_swap_and_cache() to tell it, which will also have shown one of those "swap_free" errors (but with much less information). Similar checks in fork's copy_one_pte()? No, that would be more noisy than helpful: we'll see them when parent and child exec or exit. Where do_nonlinear_fault() calls print_bad_pte(): omit !VM_CAN_NONLINEAR case, that could only be a bug in sys_remap_file_pages(), not a bad pte. VM_FAULT_OOM rather than VM_FAULT_SIGBUS? Well, okay, that is consistent with what happens if do_swap_page() operates a bad swap entry; but don't we have patches to be more careful about killing when VM_FAULT_OOM? Signed-off-by: Hugh Dickins <hugh@veritas.com> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Cc: Christoph Lameter <cl@linux-foundation.org> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Hugh Dickins authored
print_bad_pte() is so far being called only when zap_pte_range() finds negative page_mapcount, or there's a fault on a pte_file where it does not belong. That's weak coverage when we suspect pagetable corruption. Originally, it was called when vm_normal_page() found an invalid pfn: but pfn_valid is expensive on some architectures and configurations, so 2.6.24 put that under CONFIG_DEBUG_VM (which doesn't help in the field), then 2.6.26 replaced it by a VM_BUG_ON (likewise). Reinstate the print_bad_pte() in vm_normal_page(), but use a cheaper test than pfn_valid(): memmap_init_zone() (used in bootup and hotplug) keep a __read_mostly note of the highest_memmap_pfn, vm_normal_page() then check pfn against that. We could call this pfn_plausible() or pfn_sane(), but I doubt we'll need it elsewhere: of course it's not reliable, but gives much stronger pagetable validation on many boxes. Also use print_bad_pte() when the pte_special bit is found outside a VM_PFNMAP or VM_MIXEDMAP area, instead of VM_BUG_ON. Signed-off-by: Hugh Dickins <hugh@veritas.com> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Cc: Christoph Lameter <cl@linux-foundation.org> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Hugh Dickins authored
Now that bad pages are kept out of circulation, there is no need for the infamous page_remove_rmap() BUG() - once that page is freed, its negative mapcount will issue a "Bad page state" message and the page won't be freed. Removing the BUG() allows more info, on subsequent pages, to be gathered. We do have more info about the page at this point than bad_page() can know - notably, what the pmd is, which might pinpoint something like low 64kB corruption - but page_remove_rmap() isn't given the address to find that. In practice, there is only one call to page_remove_rmap() which has ever reported anything, that from zap_pte_range() (usually on exit, sometimes on munmap). It has all the info, so remove page_remove_rmap()'s "Eeek" message and leave it all to zap_pte_range(). mm/memory.c already has a hardly used print_bad_pte() function, showing some of the appropriate info: extend it to show what we want for the rmap case: pte info, page info (when there is a page) and vma info to compare. zap_pte_range() already knows the pmd, but print_bad_pte() is easier to use if it works that out for itself. Some of this info is also shown in bad_page()'s "Bad page state" message. Keep them separate, but adjust them to match each other as far as possible. Say "Bad page map" in print_bad_pte(), and add a TAINT_BAD_PAGE there too. print_bad_pte() show current->comm unconditionally (though it should get repeated in the usually irrelevant stack trace): sorry, I misled Nick Piggin to make it conditional on vm_mm == current->mm, but current->mm is already NULL in the exit case. Usually current->comm is good, though exceptionally it may not be that of the mm (when "swapoff" for example). Signed-off-by: Hugh Dickins <hugh@veritas.com> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Cc: Christoph Lameter <cl@linux-foundation.org> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Hugh Dickins authored
Until now the bad_page() checkers have special-cased PageReserved, keeping those pages out of circulation thereafter. Now extend the special case to all: we want to keep ANY page with bad state out of circulation - the "free" page may well be in use by something. Leave the bad state of those pages untouched, for examination by debuggers; except for PageBuddy - leaving that set would risk bringing the page back. Signed-off-by: Hugh Dickins <hugh@veritas.com> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Cc: Christoph Lameter <cl@linux-foundation.org> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Hugh Dickins authored
Simplify the PAGE_FLAGS checking and clearing when freeing and allocating a page: check the same flags as before when freeing, clear ALL the flags (unless PageReserved) when freeing, check ALL flags off when allocating. Signed-off-by: Hugh Dickins <hugh@veritas.com> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Cc: Christoph Lameter <cl@linux-foundation.org> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Dmitri Monakhov authored
In case of error extending write may have instantiated a few blocks outside i_size. We need to trim these blocks. We have to do it *regardless* to blocksize. At least ext2, ext3 and reiserfs interpret (i_size < biggest block) condition as error. Fsck will complain about wrong i_size. Then fsck will fix the error by changing i_size according to the biggest block. This is bad because this blocks contain garbage from previous write attempt. And result in data corruption. ####TESTCASE_BEGIN $touch /mnt/test/BIG_FILE ## at this moment /mnt/test/BIG_FILE size and blocks equal to zero open("/mnt/test/BIG_FILE", O_WRONLY|O_CREAT|O_DIRECT, 0666) = 3 write(3, "aaaaaaaaaaaa"..., 104857600) = -1 ENOSPC (No space left on device) ## size and block sould't be changed because write op failed. $stat /mnt/test/BIG_FILE File: `/mnt/test/BIG_FILE' Size: 0 Blocks: 110896 IO Block: 1024 regular empty file <<<<<<<<^^^^^^^^^^^^^^^^^^^^^^^^^^^^^file size is less than biggest block idx Device: fe07h/65031d Inode: 14 Links: 1 Access: (0644/-rw-r--r--) Uid: ( 0/ root) Gid: ( 0/ root) Access: 2007-01-24 20:03:38.000000000 +0300 Modify: 2007-01-24 20:03:38.000000000 +0300 Change: 2007-01-24 20:03:39.000000000 +0300 #fsck.ext3 -f /dev/VG/test e2fsck 1.39 (29-May-2006) Pass 1: Checking inodes, blocks, and sizes Inode 14, i_size is 0, should be 56556544. Fix<y>? yes Pass 2: Checking directory structure .... #####TESTCASE_ENDdiff --git a/fs/direct-io.c b/fs/direct-io.c index af0558d..4e88bea 100644 [akpm@linux-foundation.org: use i_size_read()] Signed-off-by: Dmitri Monakhov <dmonakhov@openvz.org> Cc: Zach Brown <zach.brown@oracle.com> Cc: Nick Piggin <npiggin@suse.de> Cc: Badari Pulavarty <pbadari@us.ibm.com> Cc: Chris Mason <chris.mason@oracle.com> Cc: Dave Chinner <david@fromorbit.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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