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  1. Aug 09, 2013
  2. Aug 06, 2013
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  5. Jul 30, 2013
  6. Jul 26, 2013
  7. Jul 22, 2013
    • Linus Torvalds's avatar
      Linux 3.11-rc2 · 3b2f64d0
      Linus Torvalds authored
      3b2f64d0
    • Linus Torvalds's avatar
      Merge tag 'acpi-video-3.11' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm · ea45ea70
      Linus Torvalds authored
      Pull ACPI video support fixes from Rafael Wysocki:
       "I'm sending a separate pull request for this as it may be somewhat
        controversial.  The breakage addressed here is not really new and the
        fixes may not satisfy all users of the affected systems, but we've had
        so much back and forth dance in this area over the last several weeks
        that I think it's time to actually make some progress.
      
        The source of the problem is that about a year ago we started to tell
        BIOSes that we're compatible with Windows 8, which we really need to
        do, because some systems shipping with Windows 8 are tested with it
        and nothing else, so if we tell their BIOSes that we aren't compatible
        with Windows 8, we expose our users to untested BIOS/AML code paths.
      
        However, as it turns out, some Windows 8-specific AML code paths are
        not tested either, because Windows 8 actually doesn't use the ACPI
        methods containing them, so if we declare Windows 8 compatibility and
        attempt to use those ACPI methods, things break.  That occurs mostly
        in the backlight support area where in particular the _BCM and _BQC
        methods are plain unusable on some systems if the OS declares Windows
        8 compatibility.
      
        [ The additional twist is that they actually become usable if the OS
          says it is not compatible with Windows 8, but that may cause
          problems to show up elsewhere ]
      
        Investigation carried out by Matthew Garrett indicates that what
        Windows 8 does about backlight is to leave backlight control up to
        individual graphics drivers.  At least there's evidence that it does
        that if the Intel graphics driver is used, so we've decided to follow
        Windows 8 in that respect and allow i915 to control backlight (Daniel
        likes that part).
      
        The first commit from Aaron Lu makes ACPICA export the variable from
        which we can infer whether or not the BIOS believes that we are
        compatible with Windows 8.
      
        The second commit from Matthew Garrett prepares the ACPI video driver
        by making it initialize the ACPI backlight even if it is not going to
        be used afterward (that is needed for backlight control to work on
        Thinkpads).
      
        The third commit implements the actual workaround making i915 take
        over backlight control if the firmware thinks it's dealing with
        Windows 8 and is based on the work of multiple developers, including
        Matthew Garrett, Chun-Yi Lee, Seth Forshee, and Aaron Lu.
      
        The final commit from Aaron Lu makes us follow Windows 8 by informing
        the firmware through the _DOS method that it should not carry out
        automatic brightness changes, so that brightness can be controlled by
        GUI.
      
        Hopefully, this approach will allow us to avoid using blacklists of
        systems that should not declare Windows 8 compatibility just to avoid
        backlight control problems in the future.
      
         - Change from Aaron Lu makes ACPICA export a variable which can be
           used by driver code to determine whether or not the BIOS believes
           that we are compatible with Windows 8.
      
         - Change from Matthew Garrett makes the ACPI video driver initialize
           the ACPI backlight even if it is not going to be used afterward
           (that is needed for backlight control to work on Thinkpads).
      
         - Fix from Rafael J Wysocki implements Windows 8 backlight support
           workaround making i915 take over bakclight control if the firmware
           thinks it's dealing with Windows 8.  Based on the work of multiple
           developers including Matthew Garrett, Chun-Yi Lee, Seth Forshee,
           and Aaron Lu.
      
         - Fix from Aaron Lu makes the kernel follow Windows 8 by informing
           the firmware through the _DOS method that it should not carry out
           automatic brightness changes, so that brightness can be controlled
           by GUI"
      
      * tag 'acpi-video-3.11' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
        ACPI / video: no automatic brightness changes by win8-compatible firmware
        ACPI / video / i915: No ACPI backlight if firmware expects Windows 8
        ACPI / video: Always call acpi_video_init_brightness() on init
        ACPICA: expose OSI version
      ea45ea70
  8. Jul 21, 2013
    • Linus Torvalds's avatar
      Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 · 90db76e8
      Linus Torvalds authored
      Pull ext[34] tmpfile bugfix from Ted Ts'o:
       "Fix regression caused by commit af51a2ac which added ->tmpfile()
        support (along with a similar fix for ext3)"
      
      * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
        ext3: fix a BUG when opening a file with O_TMPFILE flag
        ext4: fix a BUG when opening a file with O_TMPFILE flag
      90db76e8
    • Zheng Liu's avatar
      ext3: fix a BUG when opening a file with O_TMPFILE flag · dda5690d
      Zheng Liu authored
      
      
      When we try to open a file with O_TMPFILE flag, we will trigger a bug.
      The root cause is that in ext4_orphan_add() we check ->i_nlink == 0 and
      this check always fails because we set ->i_nlink = 1 in
      inode_init_always().  We can use the following program to trigger it:
      
      int main(int argc, char *argv[])
      {
      	int fd;
      
      	fd = open(argv[1], O_TMPFILE, 0666);
      	if (fd < 0) {
      		perror("open ");
      		return -1;
      	}
      	close(fd);
      	return 0;
      }
      
      The oops message looks like this:
      
      kernel: kernel BUG at fs/ext3/namei.c:1992!
      kernel: invalid opcode: 0000 [#1] SMP
      kernel: Modules linked in: ext4 jbd2 crc16 cpufreq_ondemand ipv6 dm_mirror dm_region_hash dm_log dm_mod parport_pc parport serio_raw sg dcdbas pcspkr i2c_i801 ehci_pci ehci_hcd button acpi_cpufreq mperf e1000e ptp pps_core ttm drm_kms_helper drm hwmon i2c_algo_bit i2c_core ext3 jbd sd_mod ahci libahci libata scsi_mod uhci_hcd
      kernel: CPU: 0 PID: 2882 Comm: tst_tmpfile Not tainted 3.11.0-rc1+ #4
      kernel: Hardware name: Dell Inc. OptiPlex 780 /0V4W66, BIOS A05 08/11/2010
      kernel: task: ffff880112d30050 ti: ffff8801124d4000 task.ti: ffff8801124d4000
      kernel: RIP: 0010:[<ffffffffa00db5ae>] [<ffffffffa00db5ae>] ext3_orphan_add+0x6a/0x1eb [ext3]
      kernel: RSP: 0018:ffff8801124d5cc8  EFLAGS: 00010202
      kernel: RAX: 0000000000000000 RBX: ffff880111510128 RCX: ffff8801114683a0
      kernel: RDX: 0000000000000000 RSI: ffff880111510128 RDI: ffff88010fcf65a8
      kernel: RBP: ffff8801124d5d18 R08: 0080000000000000 R09: ffffffffa00d3b7f
      kernel: R10: ffff8801114683a0 R11: ffff8801032a2558 R12: 0000000000000000
      kernel: R13: ffff88010fcf6800 R14: ffff8801032a2558 R15: ffff8801115100d8
      kernel: FS:  00007f5d172b5700(0000) GS:ffff880117c00000(0000) knlGS:0000000000000000
      kernel: CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
      kernel: CR2: 00007f5d16df15d0 CR3: 0000000110b1d000 CR4: 00000000000407f0
      kernel: Stack:
      kernel: 000000000000000c ffff8801048a7dc8 ffff8801114685a8 ffffffffa00b80d7
      kernel: ffff8801124d5e38 ffff8801032a2558 ffff88010ce24d68 0000000000000000
      kernel: ffff88011146b300 ffff8801124d5d44 ffff8801124d5d78 ffffffffa00db7e1
      kernel: Call Trace:
      kernel: [<ffffffffa00b80d7>] ? journal_start+0x8c/0xbd [jbd]
      kernel: [<ffffffffa00db7e1>] ext3_tmpfile+0xb2/0x13b [ext3]
      kernel: [<ffffffff821076f8>] path_openat+0x11f/0x5e7
      kernel: [<ffffffff821c86b4>] ? list_del+0x11/0x30
      kernel: [<ffffffff82065fa2>] ?  __dequeue_entity+0x33/0x38
      kernel: [<ffffffff82107cd5>] do_filp_open+0x3f/0x8d
      kernel: [<ffffffff82112532>] ? __alloc_fd+0x50/0x102
      kernel: [<ffffffff820f9296>] do_sys_open+0x13b/0x1cd
      kernel: [<ffffffff820f935c>] SyS_open+0x1e/0x20
      kernel: [<ffffffff82398c02>] system_call_fastpath+0x16/0x1b
      kernel: Code: 39 c7 0f 85 67 01 00 00 0f b7 03 25 00 f0 00 00 3d 00 40 00 00 74 18 3d 00 80 00 00 74 11 3d 00 a0 00 00 74 0a 83 7b 48 00 74 04 <0f> 0b eb fe 49 8b 85 50 03 00 00 4c 89 f6 48 c7 c7 c0 99 0e a0
      kernel: RIP  [<ffffffffa00db5ae>] ext3_orphan_add+0x6a/0x1eb [ext3]
      kernel: RSP <ffff8801124d5cc8>
      
      Here we couldn't call clear_nlink() directly because in d_tmpfile() we
      will call inode_dec_link_count() to decrease ->i_nlink.  So this commit
      tries to call d_tmpfile() before ext4_orphan_add() to fix this problem.
      
      Signed-off-by: default avatarZheng Liu <wenqing.lz@taobao.com>
      Signed-off-by: default avatar"Theodore Ts'o" <tytso@mit.edu>
      Cc: Jan Kara <jack@suse.cz>
      Cc: Al Viro <viro@zeniv.linux.org.uk>
      dda5690d