- 22 Jan, 2013 1 commit
-
-
Namjae Jeon authored
Add __init to functions in init_f2fs_fs for code consistency. Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com> Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
-
- 15 Jan, 2013 3 commits
-
-
Namjae Jeon authored
As the "status" debugfs entry will be maintained for entire F2FS filesystem irrespective of the number of partitions. So, we can move the initialization to the init part of the f2fs and destroy will be done from exit part. After making changes, for individual partition mount - entry creation code will not be executed. Signed-off-by: Jianpeng Ma <majianpeng@gmail.com> Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com> Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
-
majianpeng authored
There is an race condition between umounting f2fs and reading f2fs/status, which results in oops. Fox example: Thread A Thread B umount f2fs cat f2fs/status f2fs_destroy_stats() { stat_show() { list_for_each_entry_safe(&f2fs_stat_list) list_del(&si->stat_list); mutex_lock(&si->stat_lock); si->sbi = NULL; mutex_unlock(&si->stat_lock); kfree(sbi->stat_info); } mutex_lock(&si->stat_lock) <- si is gone. ... } Solution with a global lock: f2fs_stat_mutex: Thread A Thread B umount f2fs cat f2fs/status f2fs_destroy_stats() { stat_show() { mutex_lock(&f2fs_stat_mutex); list_del(&si->stat_list); mutex_unlock(&f2fs_stat_mutex); kfree(sbi->stat_info); mutex_lock(&f2fs_stat_mutex); } list_for_each_entry_safe(&f2fs_stat_list) ... mutex_unlock(&f2fs_stat_mutex); } Signed-off-by: Jianpeng Ma <majianpeng@gmail.com> [jaegeuk.kim@samsung.com: fix typos, description, and remove the existing lock] Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
-
Namjae Jeon authored
Let's consider the usage of blk_plug in f2fs_write_data_pages(). We can come up with the two issues: lock contention and task awareness. 1. Merging bios prior to grabing "queue lock" The f2fs merges consecutive IOs in the file system level before submitting any bios, which is similar with the back merge by the plugging mechanism in attempt_plug_merge(). Both of them need to acquire no queue lock. 2. Merging policy with respect to tasks The f2fs merges IOs as much as possible regardless of tasks, while blk-plugging is conducted on a basis of tasks. As we can understand there are trade-offs, f2fs tries to maximize the write performance with well-merged bios. As a result, if f2fs produces many consecutive but separated bios in writepages(), it would be good to use blk-plugging since f2fs would be able to avoid queue lock contention in the block layer by merging them. But, f2fs merges IOs and submit one bio, which means that there are not much chances to merge bios by attempt_plug_merge(). However, f2fs has already been used blk_plug by triggering generic_writepages() in f2fs_write_data_pages(). So to make the overall code consistency, I'd like to remove blk_plug there. Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com> Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
-
- 14 Jan, 2013 2 commits
-
-
Namjae Jeon authored
In call to f2fs_delete_entry, 'dir' time modification code is put at two places. So, remove the redundant code for timing update. Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com> Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
-
Namjae Jeon authored
Since, f2fs supports only 4KB blocksize, which is set at the beginning in f2fs_fill_super. So, we do not need to again check this blocksize setting in such case. Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com> Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
-
- 11 Jan, 2013 2 commits
-
-
Jaegeuk Kim authored
The f2fs_fallocate() has two operations: punch_hole and expand_size. Only in the case of punch_hole, dirty node pages can be produced, so let's trigger f2fs_balance_fs() in this case only. Furthermore, let's trigger it at every data truncation routine. Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
-
Jaegeuk Kim authored
The f2fs_balance_fs() is to check the number of free sections and decide whether it needs to conduct cleaning or not. If there are not enough free sections, the cleaning job should be started. In order to control an amount of free sections even under high utilization, f2fs should call f2fs_balance_fs at all the VFS interfaces that are able to produce dirty pages. This patch adds the function calls in the missing interfaces as follows. 1. f2fs_setxattr() The f2fs_setxattr() produces dirty node pages so that we should call f2fs_balance_fs() either likewise doing in other VFS interfaces such as f2fs_lookup(), f2fs_mkdir(), and so on. 2. f2fs_sync_file() We should guarantee serving free sections for syncing metadata during fsync. Previously, there is no space check before triggering checkpoint and sync_node_pages. Therefore, if a bunch of fsync calls are triggered under 100% of FS utilization, f2fs is able to be faced with no free sections, resulting in BUG_ON(). 3. f2fs_sync_fs() Before calling write_checkpoint(), we should guarantee that there are minimum free sections. 4. f2fs_write_inode() f2fs_write_inode() is also able to produce dirty node pages. Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
-
- 09 Jan, 2013 1 commit
-
-
Jaegeuk Kim authored
I'd like to revisit the f2fs_gc flow and rewrite as follows. 1. In practical, the nGC parameter of f2fs_gc is meaningless. So, let's remove it. 2. Background GC marks victim blocks as dirty one at a time. 3. Foreground GC should do cleaning job until acquiring enough free sections. Afterwards, it needs to do checkpoint. Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
-
- 04 Jan, 2013 8 commits
-
-
Jaegeuk Kim authored
This patch resolves Coverity #753102: >>> No check of the return value of "f2fs_add_link(&dent, inode)". Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
-
Jaegeuk Kim authored
This patch resolves Coverity #751303: >>> CID 753103: Explicit null dereferenced (FORWARD_NULL) Passing null >>> pointer "value" to function "f2fs_acl_from_disk(char const *, size_t)", which dereferences it. [Error path] - value = NULL; - retval = 0 by f2fs_getxattr(); - f2fs_acl_from_disk(value:NULL, ...); Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
-
Jaegeuk Kim authored
This patch resolves Coverity #753112. In practical, the existing code flow does not fall into the reported errorneous path. But, anyway, let's avoid this for future. Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
-
Huajun Li authored
Update partition info output under debug FS to reflect segment layout correctly. Signed-off-by: Huajun Li <huajun.li.lee@gmail.com> Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
-
Huajun Li authored
document to reflect the layout generated by mkfs.f2fs . Signed-off-by: Huajun Li <huajun.li.lee@gmail.com> Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
-
Namjae Jeon authored
While creating a new entry for addition to the list(orphan inode list and fsync inode entry list), there is no need to call HEAD initialization for these entries. So, remove that init part. Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com> Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
-
Namjae Jeon authored
After doing a punch hole or expanding inode doing fallocation. The change and modification time are not update for the file. So, update time after no issue is observed in fallocate. Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com> Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
-
Namjae Jeon authored
Introduced f2fs_msg function to differentiate f2fs specific messages in the log. And, added few informative prints in the mount path, to convey proper error in case of mount failure. Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com> Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
-
- 03 Jan, 2013 17 commits
-
-
git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrlLinus Torvalds authored
Pull pinctrl fixes from Linus Walleij: "A first round of pinctrl fixes for v3.8: - i.MX5 register configuration - Swap a kfree to devm_kfree() to avoid memory corruption in the at91 driver - Add the missing device tree binding doc for the SIRF pin controller - Enable the SIRF GPIO pull up/down configuration from the device tree, it was previously retired from the hard-coded approach. - NULL check for the prcm_base in the Nomadik pin controller. - Provide the prcm_base from the device tree in the DT boot path for the Nomadik pin controller." * tag 'pinctrl-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: ARM: ux500: add pinctrl address resources pinctrl: nomadik: return if prcm_base is NULL pinctrl: sirf: enable GPIO pullup/down configuration from dts pinctrl: sirf: add missing DT-binding document pinctrl: fix comment mistake drivers/pinctrl/pinctrl-at91.c: convert kfree to devm_kfree pinctrl: imx5: fix GPIO_8 pad CAN1_RXCAN configuration
-
git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fsLinus Torvalds authored
Pull f2fs bug fixes from Jaegeuk Kim: "This patch-set includes two major bug fixes: - incorrect IUsed provided by *df -i*, and - lookup failure of parent inodes in corner cases. [Other Bug Fixes] - Fix error handling routines - Trigger recovery process correctly - Resolve build failures due to missing header files [Etc] - Add a MAINTAINERS entry for f2fs - Fix and clean up variables, functions, and equations - Avoid warnings during compilation" * tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: f2fs: unify string length declarations and usage f2fs: clean up unused variables and return values f2fs: clean up the start_bidx_of_node function f2fs: remove unneeded variable from f2fs_sync_fs f2fs: fix fsync_inode list addition logic and avoid invalid access to memory f2fs: remove unneeded initialization of nr_dirty in dirty_seglist_info f2fs: handle error from f2fs_iget_nowait f2fs: fix equation of has_not_enough_free_secs() f2fs: add MAINTAINERS entry f2fs: return a default value for non-void function f2fs: invalidate the node page if allocation is failed f2fs: add missing #include <linux/prefetch.h> f2fs: do f2fs_balance_fs in front of dir operations f2fs: should recover orphan and fsync data f2fs: fix handling errors got by f2fs_write_inode f2fs: fix up f2fs_get_parent issue to retrieve correct parent inode number f2fs: fix wrong calculation on f_files in statfs f2fs: remove set_page_dirty for atomic f2fs_end_io_write
-
git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-3.0-fixesLinus Torvalds authored
Pull GFS2 fixes from Steven Whitehouse: "Here are four small bug fixes for GFS2. There is no common theme here really, just a few items that were fixed recently. The first fixes lock name generation when the glock number is 0. The second fixes a race allocating reservation structures and the final two fix a performance issue by making small changes in the allocation code." * git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-3.0-fixes: GFS2: Reset rd_last_alloc when it reaches the end of the rgrp GFS2: Stop looking for free blocks at end of rgrp GFS2: Fix race in gfs2_rs_alloc GFS2: Initialize hex string to '0'
-
git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpcLinus Torvalds authored
Pull powerpc fixes from Ben Herrenschmidt: "Here are a couple of small powerpc fixes. They aren't new bugs (and they are both CCed to stable) but I didn't see the point of sitting on the fixes any longer." * 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: powerpc: Add missing NULL terminator to avoid boot panic on PPC40x powerpc/vdso: Remove redundant locking in update_vsyscall_tz()
-
Luck, Tony authored
Linux was granted a new system call to load modules by file descriptor in commit 34e1169d ("module: add syscall to load module from fd"). Wire it up for ia64 (ready for the Chrome port :-) Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Gabor Juhos authored
The missing NULL terminator can cause a panic on PPC405 boards during boot: Linux/PowerPC load: console=ttyS0,115200 root=/dev/mtdblock1 rootfstype=squashfs,jffs2 noinitrd init=/etc/preinit Finalizing device tree... flat tree at 0x6a5160 bootconsole [udbg0] enabled Page fault in user mode with in_atomic() = 1 mm = (null) NIP = c0275f50 MSR = fffffffe Oops: Weird page fault, sig: 11 [#1] PowerPC 40x Platform Modules linked in: NIP: c0275f50 LR: c0275f60 CTR: c0280000 REGS: c0275eb0 TRAP: 636f7265 Not tainted (3.7.1) MSR: fffffffe <VEC,VSX,EE,PR,FP,ME,SE,BE,IR,DR,PMM,RI> CR: c06a6190 XER: 00000001 TASK = c02662a8[0] 'swapper' THREAD: c0274000 GPR00: c0275ec0 c000c658 c027c4bf 00000000 c0275ee0 c000a0ec c020a1a8 c020a1f0 GPR08: c020f631 c020f404 c025f078 c025f080 c0275f10 Call Trace: ---[ end trace 31fd0ba7d8756001 ]--- Kernel panic - not syncing: Attempted to kill the idle task! The panic happens since commit 9597abe0 (sections: fix section conflicts in arch/powerpc), however the root cause of this is that the NULL terminator were not added in commit a4f740cf (of/flattree: Add of_flat_dt_match() helper function). Cc: Grant Likely <grant.likely@secretlab.ca> Cc: <stable@vger.kernel.org> Signed-off-by: Gabor Juhos <juhosg@openwrt.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
-
Shan Hai authored
The locking in update_vsyscall_tz() is not only unnecessary because the vdso code copies the data unproteced in __kernel_gettimeofday() but also introduces a hard to reproduce race condition between update_vsyscall() and update_vsyscall_tz(), which causes user space process to loop forever in vdso code. The following patch removes the locking from update_vsyscall_tz(). Locking is not only unnecessary because the vdso code copies the data unprotected in __kernel_gettimeofday() but also erroneous because updating the tb_update_count is not atomic and introduces a hard to reproduce race condition between update_vsyscall() and update_vsyscall_tz(), which further causes user space process to loop forever in vdso code. The below scenario describes the race condition, x==0 Boot CPU other CPU proc_P: x==0 timer interrupt update_vsyscall x==1 x++;sync settimeofday update_vsyscall_tz x==2 x++;sync x==3 sync;x++ sync;x++ proc_P: x==3 (loops until x becomes even) Because the ++ operator would be implemented as three instructions and not atomic on powerpc. A similar change was made for x86 in commit 6c260d58 ("x86: vdso: Remove bogus locking in update_vsyscall_tz") Signed-off-by: Shan Hai <shan.hai@windriver.com> CC: <stable@vger.kernel.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
-
Linus Torvalds authored
-
git://git.kernel.org/pub/scm/linux/kernel/git/cooloney/linux-ledsLinus Torvalds authored
Pull LED fix from Bryan Wu. * 'fixes-for-3.8' of git://git.kernel.org/pub/scm/linux/kernel/git/cooloney/linux-leds: leds: leds-gpio: set devm_gpio_request_one() flags param correctly
-
Javier Martinez Canillas authored
commit a99d76f9 leds: leds-gpio: use gpio_request_one changed the leds-gpio driver to use gpio_request_one() instead of gpio_request() + gpio_direction_output() Unfortunately, it also made a semantic change that breaks the leds-gpio driver. The gpio_request_one() flags parameter was set to: GPIOF_DIR_OUT | (led_dat->active_low ^ state) Since GPIOF_DIR_OUT is 0, the final flags value will just be the XOR'ed value of led_dat->active_low and state. This value were used to distinguish between HIGH/LOW output initial level and call gpio_direction_output() accordingly. With this new semantic gpio_request_one() will take the flags value of 1 as a configuration of input direction (GPIOF_DIR_IN) and will call gpio_direction_input() instead of gpio_direction_output(). int gpio_request_one(unsigned gpio, unsigned long flags, const char *label) { .. if (flags & GPIOF_DIR_IN) err = gpio_direction_input(gpio); else err = gpio_direction_output(gpio, (flags & GPIOF_INIT_HIGH) ? 1 : 0); .. } The right semantic is to evaluate led_dat->active_low ^ state and set the output initial level explicitly. Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk> Reported-by: Arnaud Patard <arnaud.patard@rtp-net.org> Tested-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com> Signed-off-by: Bryan Wu <cooloney@gmail.com>
-
git://www.linux-watchdog.org/linux-watchdogLinus Torvalds authored
Pull watchdog fixes from Wim Van Sebroeck: "This fixes some small errors in the new da9055 driver, eliminates a compiler warning and adds DT support for the twl4030_wdt driver (so that we can have multiple watchdogs with DT on the omap platforms)." * git://www.linux-watchdog.org/linux-watchdog: watchdog: twl4030_wdt: add DT support watchdog: omap_wdt: eliminate unused variable and a compiler warning watchdog: da9055: Don't update wdt_dev->timeout in da9055_wdt_set_timeout error path watchdog: da9055: Fix invalid free of devm_ allocated data
-
git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pciLinus Torvalds authored
Pull PCI updates from Bjorn Helgaas: "Some fixes for v3.8. They include a fix for the new SR-IOV sysfs management support, an expanded quirk for Ricoh SD card readers, a Stratus DMI quirk fix, and a PME polling fix." * tag '3.8-pci-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: PCI: Reduce Ricoh 0xe822 SD card reader base clock frequency to 50MHz PCI/PM: Do not suspend port if any subordinate device needs PME polling PCI: Add PCIe Link Capability link speed and width names PCI: Work around Stratus ftServer broken PCIe hierarchy (fix DMI check) PCI: Remove spurious error for sriov_numvfs store and simplify flow
-
David Howells authored
Commit 56c176c9 ("UAPI: strip the _UAPI prefix from header guards during header installation") strips the _UAPI prefix from header guards, but only if there's a single space between the cpp directive and the label. Make it more flexible and able to handle tabs and multiple white space characters. Signed-off-by: David Howells <dhowell@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
David Howells authored
Empty files can get deleted by the patch program, so remove empty Kbuild files and their links from the parent Kbuilds. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Linus Torvalds authored
Merge tag 'ecryptfs-3.8-rc2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tyhicks/ecryptfs Pull ecryptfs fixes from Tyler Hicks: "Two self-explanatory fixes and a third patch which improves performance: when overwriting a full page in the eCryptfs page cache, skip reading in and decrypting the corresponding lower page." * tag 'ecryptfs-3.8-rc2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tyhicks/ecryptfs: fs/ecryptfs/crypto.c: make ecryptfs_encode_for_filename() static eCryptfs: fix to use list_for_each_entry_safe() when delete items eCryptfs: Avoid unnecessary disk read and data decryption during writing
-
git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-clientLinus Torvalds authored
Pull Ceph fixes from Sage Weil: "Two of Alex's patches deal with a race when reseting server connections for open RBD images, one demotes some non-fatal BUGs to WARNs, and my patch fixes a protocol feature bit failure path." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: libceph: fix protocol feature mismatch failure path libceph: WARN, don't BUG on unexpected connection states libceph: always reset osds when kicking libceph: move linger requests sooner in kick_requests()
-
Mel Gorman authored
Sasha was fuzzing with trinity and reported the following problem: BUG: sleeping function called from invalid context at kernel/mutex.c:269 in_atomic(): 1, irqs_disabled(): 0, pid: 6361, name: trinity-main 2 locks held by trinity-main/6361: #0: (&mm->mmap_sem){++++++}, at: [<ffffffff810aa314>] __do_page_fault+0x1e4/0x4f0 #1: (&(&mm->page_table_lock)->rlock){+.+...}, at: [<ffffffff8122f017>] handle_pte_fault+0x3f7/0x6a0 Pid: 6361, comm: trinity-main Tainted: G W 3.7.0-rc2-next-20121024-sasha-00001-gd95ef01-dirty #74 Call Trace: __might_sleep+0x1c3/0x1e0 mutex_lock_nested+0x29/0x50 mpol_shared_policy_lookup+0x2e/0x90 shmem_get_policy+0x2e/0x30 get_vma_policy+0x5a/0xa0 mpol_misplaced+0x41/0x1d0 handle_pte_fault+0x465/0x6a0 This was triggered by a different version of automatic NUMA balancing but in theory the current version is vunerable to the same problem. do_numa_page -> numa_migrate_prep -> mpol_misplaced -> get_vma_policy -> shmem_get_policy It's very unlikely this will happen as shared pages are not marked pte_numa -- see the page_mapcount() check in change_pte_range() -- but it is possible. To address this, this patch restores sp->lock as originally implemented by Kosaki Motohiro. In the path where get_vma_policy() is called, it should not be calling sp_alloc() so it is not necessary to treat the PTL specially. Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Tested-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Mel Gorman <mgorman@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
- 02 Jan, 2013 6 commits
-
-
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4Linus Torvalds authored
Pull ext4 bug fixes from Ted Ts'o: "Various bug fixes for ext4. Perhaps the most serious bug fixed is one which could cause file system corruptions when performing file punch operations." * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: ext4: avoid hang when mounting non-journal filesystems with orphan list ext4: lock i_mutex when truncating orphan inodes ext4: do not try to write superblock on ro remount w/o journal ext4: include journal blocks in df overhead calcs ext4: remove unaligned AIO warning printk ext4: fix an incorrect comment about i_mutex ext4: fix deadlock in journal_unmap_buffer() ext4: split off ext4_journalled_invalidatepage() jbd2: fix assertion failure in jbd2_journal_flush() ext4: check dioread_nolock on remount ext4: fix extent tree corruption caused by hole punch
-
Hugh Dickins authored
Remove the unused argument (formerly no_context) from mpol_parse_str() and from mpol_to_str(). Signed-off-by: Hugh Dickins <hughd@google.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Hugh Dickins authored
Recently I suggested using "mount -o remount,mpol=local /tmp" in NUMA mempolicy testing. Very nasty. Reading /proc/mounts, /proc/pid/mounts or /proc/pid/mountinfo may then corrupt one bit of kernel memory, often in a page table (causing "Bad swap" or "Bad page map" warning or "Bad pagetable" oops), sometimes in a vm_area_struct or rbnode or somewhere worse. "mpol=prefer" and "mpol=prefer:Node" are equally toxic. Recent NUMA enhancements are not to blame: this dates back to 2.6.35, when commit e17f74af "mempolicy: don't call mpol_set_nodemask() when no_context" skipped mpol_parse_str()'s call to mpol_set_nodemask(), which used to initialize v.preferred_node, or set MPOL_F_LOCAL in flags. With slab poisoning, you can then rely on mpol_to_str() to set the bit for node 0x6b6b, probably in the next page above the caller's stack. mpol_parse_str() is only called from shmem_parse_options(): no_context is always true, so call it unused for now, and remove !no_context code. Set v.nodes or v.preferred_node or MPOL_F_LOCAL as mpol_to_str() might expect. Then mpol_to_str() can ignore its no_context argument also, the mpol being appropriately initialized whether contextualized or not. Rename its no_context unused too, and let subsequent patch remove them (that's not needed for stable backporting, which would involve rejects). I don't understand why MPOL_LOCAL is described as a pseudo-policy: it's a reasonable policy which suffers from a confusing implementation in terms of MPOL_PREFERRED with MPOL_F_LOCAL. I believe this would be much more robust if MPOL_LOCAL were recognized in switch statements throughout, MPOL_F_LOCAL deleted, and MPOL_PREFERRED use the (possibly empty) nodes mask like everyone else, instead of its preferred_node variant (I presume an optimization from the days before MPOL_LOCAL). But that would take me too long to get right and fully tested. Signed-off-by: Hugh Dickins <hughd@google.com> Cc: stable@vger.kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Eric Wong authored
EPOLL_CTL_MOD sets the interest mask before calling f_op->poll() to ensure events are not missed. Since the modifications to the interest mask are not protected by the same lock as ep_poll_callback, we need to ensure the change is visible to other CPUs calling ep_poll_callback. We also need to ensure f_op->poll() has an up-to-date view of past events which occured before we modified the interest mask. So this barrier also pairs with the barrier in wq_has_sleeper(). This should guarantee either ep_poll_callback or f_op->poll() (or both) will notice the readiness of a recently-ready/modified item. This issue was encountered by Andreas Voellmy and Junchang(Jason) Wang in: http://thread.gmane.org/gmane.linux.kernel/1408782/Signed-off-by: Eric Wong <normalperson@yhbt.net> Cc: Hans Verkuil <hans.verkuil@cisco.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Davide Libenzi <davidel@xmailserver.org> Cc: Hans de Goede <hdegoede@redhat.com> Cc: Mauro Carvalho Chehab <mchehab@infradead.org> Cc: David Miller <davem@davemloft.net> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andreas Voellmy <andreas.voellmy@yale.edu> Tested-by: "Junchang(Jason) Wang" <junchang.wang@yale.edu> Cc: netdev@vger.kernel.org Cc: linux-fsdevel@vger.kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Aaro Koskinen authored
Add DT support for twl4030_wdt. This is needed to get twl4030_wdt to probe when booting with DT. Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
-
Aaro Koskinen authored
We forgot to delete this in the commit 4f4753d9 (watchdog: omap_wdt: convert to devm_ functions), and as a result the following compilation warning was introduced: drivers/watchdog/omap_wdt.c: In function 'omap_wdt_remove': drivers/watchdog/omap_wdt.c:299:19: warning: unused variable 'res' [-Wunused-variable] Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi> Reviewed-by: Paul Walmsley <paul@pwsan.com> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
-