linux/fs/proc, branch v3.4

Merge branch 'akpm' (Andrew's patch-bomb)

2012-05-18T22:56:25Z

Merge misc fixes from Andrew Morton. * emailed from Andrew Morton : (4 patches) frv: delete incorrect task prototypes causing compile fail slub: missing test for partial pages flush work in flush_all() fs, proc: fix ABBA deadlock in case of execution attempt of map_files/ entries drivers/rtc/rtc-pl031.c: configure correct wday for 2000-01-01

proc: move fd symlink i_mode calculations into tid_fd_revalidate()

2012-05-18T21:06:17Z

Instead of doing the i_mode calculations at proc_fd_instantiate() time, move them into tid_fd_revalidate(), which is where the other inode state (notably uid/gid information) is updated too. Otherwise we'll end up with stale i_mode information if an fd is re-used while the dentry still hangs around. Not that anything really *cares* (symlink permissions don't really matter), but Tetsuo Handa noticed that the owner read/write bits don't always match the state of the readability of the file descriptor, and we _used_ to get this right a long time ago in a galaxy far, far away. Besides, aside from fixing an ugly detail (that has apparently been this way since commit 61a28784028e: "proc: Remove the hard coded inode numbers" in 2006), this removes more lines of code than it adds. And it just makes sense to update i_mode in the same place we update i_uid/gid. Al Viro correctly points out that we could just do the inode fill in the inode iops ->getattr() function instead. However, that does require somewhat slightly more invasive changes, and adds yet *another* lookup of the file descriptor. We need to do the revalidate() for other reasons anyway, and have the file descriptor handy, so we might as well fill in the information at this point. Reported-by: Tetsuo Handa Cc: Al Viro Acked-by: Eric Biederman Signed-off-by: Linus Torvalds

fs, proc: fix ABBA deadlock in case of execution attempt of map_files/ entries

2012-05-18T01:00:51Z

map_files/ entries are never supposed to be executed, still curious minds might try to run them, which leads to the following deadlock ====================================================== [ INFO: possible circular locking dependency detected ] 3.4.0-rc4-24406-g841e6a6 #121 Not tainted ------------------------------------------------------- bash/1556 is trying to acquire lock: (&sb->s_type->i_mutex_key#8){+.+.+.}, at: do_lookup+0x267/0x2b1 but task is already holding lock: (&sig->cred_guard_mutex){+.+.+.}, at: prepare_bprm_creds+0x2d/0x69 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&sig->cred_guard_mutex){+.+.+.}: validate_chain+0x444/0x4f4 __lock_acquire+0x387/0x3f8 lock_acquire+0x12b/0x158 __mutex_lock_common+0x56/0x3a9 mutex_lock_killable_nested+0x40/0x45 lock_trace+0x24/0x59 proc_map_files_lookup+0x5a/0x165 __lookup_hash+0x52/0x73 do_lookup+0x276/0x2b1 walk_component+0x3d/0x114 do_last+0xfc/0x540 path_openat+0xd3/0x306 do_filp_open+0x3d/0x89 do_sys_open+0x74/0x106 sys_open+0x21/0x23 tracesys+0xdd/0xe2 -> #0 (&sb->s_type->i_mutex_key#8){+.+.+.}: check_prev_add+0x6a/0x1ef validate_chain+0x444/0x4f4 __lock_acquire+0x387/0x3f8 lock_acquire+0x12b/0x158 __mutex_lock_common+0x56/0x3a9 mutex_lock_nested+0x40/0x45 do_lookup+0x267/0x2b1 walk_component+0x3d/0x114 link_path_walk+0x1f9/0x48f path_openat+0xb6/0x306 do_filp_open+0x3d/0x89 open_exec+0x25/0xa0 do_execve_common+0xea/0x2f9 do_execve+0x43/0x45 sys_execve+0x43/0x5a stub_execve+0x6c/0xc0 This is because prepare_bprm_creds grabs task->signal->cred_guard_mutex and when do_lookup happens we try to grab task->signal->cred_guard_mutex again in lock_trace. Fix it using plain ptrace_may_access() helper in proc_map_files_lookup() and in proc_map_files_readdir() instead of lock_trace(), the caller must be CAP_SYS_ADMIN granted anyway. Signed-off-by: Cyrill Gorcunov Reported-by: Sasha Levin Cc: Konstantin Khlebnikov Cc: Pavel Emelyanov Cc: Dave Jones Cc: Vasiliy Kulikov Cc: Oleg Nesterov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

proc/pid/pagemap: correctly report non-present ptes and holes between vmas

2012-05-10T22:06:44Z

Reset the current pagemap-entry if the current pte isn't present, or if current vma is over. Otherwise pagemap reports last entry again and again. Non-present pte reporting was broken in commit 092b50bacd1c ("pagemap: introduce data structure for pagemap entry") Reporting for holes was broken in commit 5aaabe831eb5 ("pagemap: avoid splitting thp when reading /proc/pid/pagemap") Signed-off-by: Konstantin Khlebnikov Reported-by: Pavel Emelyanov Cc: Naoya Horiguchi Cc: KAMEZAWA Hiroyuki Cc: Andi Kleen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

revert "proc: clear_refs: do not clear reserved pages"

2012-04-26T04:26:34Z

Revert commit 85e72aa5384 ("proc: clear_refs: do not clear reserved pages"), which was a quick fix suitable for -stable until ARM had been moved over to the gate_vma mechanism: https://lkml.org/lkml/2012/1/14/55 With commit f9d4861f ("ARM: 7294/1: vectors: use gate_vma for vectors user mapping"), ARM does now use the gate_vma, so the PageReserved check can be removed from the proc code. Signed-off-by: Will Deacon Cc: Nicolas Pitre Acked-by: Hugh Dickins Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2012-04-12T22:16:26Z

Pull timer fixes from Thomas Gleixner: "The itimer removal one is not strictly a fix, but I really wanted to avoid a rebase of the urgent ones." * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: Revert "clocksource: Load the ACPI PM clocksource asynchronously" clockevents: tTack broadcast device mode change in tick_broadcast_switch_to_oneshot() itimer: Use printk_once instead of WARN_ONCE nohz: Fix stale jiffies update in tick_nohz_restart() tick: Document TICK_ONESHOT config option proc: stats: Use arch_idle_time for idle and iowait times if available itimer: Schedule silent NULL pointer fixup in setitimer() for removal

Merge branch 'akpm' (Andrew's patch-bomb)

2012-04-05T22:30:34Z

Merge batch of fixes from Andrew Morton: "The simple_open() cleanup was held back while I wanted for laggards to merge things. I still need to send a few checkpoint/restore patches. I've been wobbly about merging them because I'm wobbly about the overall prospects for success of the project. But after speaking with Pavel at the LSF conference, it sounds like they're further toward completion than I feared - apparently davem is at the "has stopped complaining" stage regarding the net changes. So I need to go back and re-review those patchs and their (lengthy) discussion." * emailed from Andrew Morton : (16 patches) memcg swap: use mem_cgroup_uncharge_swap fix backlight: add driver for DA9052/53 PMIC v1 C6X: use set_current_blocked() and block_sigmask() MAINTAINERS: add entry for sparse checker MAINTAINERS: fix REMOTEPROC F: typo alpha: use set_current_blocked() and block_sigmask() simple_open: automatically convert to simple_open() scripts/coccinelle/api/simple_open.cocci: semantic patch for simple_open() libfs: add simple_open() hugetlbfs: remove unregister_filesystem() when initializing module drivers/rtc/rtc-88pm860x.c: fix rtc irq enable callback fs/xattr.c:setxattr(): improve handling of allocation failures fs/xattr.c:listxattr(): fall back to vmalloc() if kmalloc() failed fs/xattr.c: suppress page allocation failure warnings from sys_listxattr() sysrq: use SEND_SIG_FORCED instead of force_sig() proc: fix mount -t proc -o AAA

proc: fix mount -t proc -o AAA

2012-04-05T22:25:50Z

The proc_parse_options() call from proc_mount() runs only once at boot time. So on any later mount attempt, any mount options are ignored because ->s_root is already initialized. As a consequence, "mount -o " will ignore the options. The only way to change mount options is "mount -o remount,". To fix this, parse the mount options unconditionally. Signed-off-by: Vasiliy Kulikov Reported-by: Arkadiusz Miskiewicz Tested-by: Arkadiusz Miskiewicz Cc: Alexey Dobriyan Cc: Al Viro Cc: Valdis Kletnieks Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

proc: stats: Use arch_idle_time for idle and iowait times if available

2012-03-30T13:43:33Z

Git commit a25cac5198d4ff28 "proc: Consider NO_HZ when printing idle and iowait times" changes the code for /proc/stat to use get_cpu_idle_time_us and get_cpu_iowait_time_us if the system is running with nohz enabled. For architectures which define arch_idle_time (currently s390 only) this is a change for the worse. The result of arch_idle_time is supposed to be the exact sleep time of the target cpu and should be used instead of the value kept by the scheduler. Signed-off-by: Martin Schwidefsky Reviewed-by: Michal Hocko Reviewed-by: Srivatsa S. Bhat Link: http://lkml.kernel.org/r/20120330122308.18720283@de.ibm.com Signed-off-by: Thomas Gleixner

Merge branch 'x86-x32-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2012-03-30T01:12:23Z

Pull x32 support for x86-64 from Ingo Molnar: "This tree introduces the X32 binary format and execution mode for x86: 32-bit data space binaries using 64-bit instructions and 64-bit kernel syscalls. This allows applications whose working set fits into a 32 bits address space to make use of 64-bit instructions while using a 32-bit address space with shorter pointers, more compressed data structures, etc." Fix up trivial context conflicts in arch/x86/{Kconfig,vdso/vma.c} * 'x86-x32-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (71 commits) x32: Fix alignment fail in struct compat_siginfo x32: Fix stupid ia32/x32 inversion in the siginfo format x32: Add ptrace for x32 x32: Switch to a 64-bit clock_t x32: Provide separate is_ia32_task() and is_x32_task() predicates x86, mtrr: Use explicit sizing and padding for the 64-bit ioctls x86/x32: Fix the binutils auto-detect x32: Warn and disable rather than error if binutils too old x32: Only clear TIF_X32 flag once x32: Make sure TS_COMPAT is cleared for x32 tasks fs: Remove missed ->fds_bits from cessation use of fd_set structs internally fs: Fix close_on_exec pointer in alloc_fdtable x32: Drop non-__vdso weak symbols from the x32 VDSO x32: Fix coding style violations in the x32 VDSO code x32: Add x32 VDSO support x32: Allow x32 to be configured x32: If configured, add x32 system calls to system call tables x32: Handle process creation x32: Signal-related system calls x86: Add #ifdef CONFIG_COMPAT to ...