1. 02 Mar, 2020 4 commits
    • Masahiro Yamada's avatar
      fixdep: remove redundant null character check · 3f9070a6
      Masahiro Yamada authored
      If *q is '\0', the condition (isalnum(*q) || *q == '_') is false anyway.
      
      It is redundant to ensure non-zero *q.
      Signed-off-by: default avatarMasahiro Yamada <masahiroy@kernel.org>
      3f9070a6
    • Masahiro Yamada's avatar
      fixdep: remove unneeded code and comments about *.ver files · 87d660f0
      Masahiro Yamada authored
      This is probably stale code. In old days (~ Linux 2.5.59), Kbuild made
      genksyms generate include/linux/modules/*.ver files.
      
      The currenct Kbuild does not generate *.ver files at all.
      Signed-off-by: default avatarMasahiro Yamada <masahiroy@kernel.org>
      87d660f0
    • Masahiro Yamada's avatar
      kbuild: remove cc-option switch from -Wframe-larger-than= · a83e4ca2
      Masahiro Yamada authored
      This CONFIG option was added by commit 35bb5b1e ("Add option to
      enable -Wframe-larger-than= on gcc 4.4"). At that time, the cc-option
      check was needed.
      
      According to Documentation/process/changes.rst, the current minimal
      supported version of GCC is 4.6, so you can assume GCC supports it.
      Clang supports it as well.
      
      Remove the cc-option switch and redundant comments.
      Signed-off-by: default avatarMasahiro Yamada <masahiroy@kernel.org>
      Reviewed-by: default avatarNathan Chancellor <natechancellor@gmail.com>
      Reviewed-by: default avatarNick Desaulniers <ndesaulniers@google.com>
      a83e4ca2
    • Masahiro Yamada's avatar
      kbuild: remove the owner check in mkcompile_h · f84fdf8d
      Masahiro Yamada authored
      This reverts a very old commit, which dates back to the pre-git era:
      
      |commit 5d1cfb5b
      |Author: Kai Germaschewski <kai@tp1.ruhr-uni-bochum.de>
      |Date:   Sat Jul 27 02:53:19 2002 -0500
      |
      |    kbuild: Fix compiling/installing as different users
      |
      |    "make bzImage && sudo make install" had the problem that during
      |    the "sudo make install" the build system would notice that the information
      |    in include/linux/compile.h is not accurate (it says "compiled by <user>",
      |    but we are root), thus causing compile.h to be updated and leading to
      |    some recompiles.
      |
      |    We now only update "compile.h" if the current user is the owner of
      |    include/linux/autoconf.h, i.e. the user who did the "make *config". So the
      |    above sequence will correctly state "compiled by <user>".
      |
      |diff --git a/scripts/mkcompile_h b/scripts/mkcompile_h
      |index 6313db96172..cd956380978 100755
      |--- a/scripts/mkcompile_h
      |+++ b/scripts/mkcompile_h
      |@@ -3,6 +3,17 @@ ARCH=$2
      | SMP=$3
      | CC=$4
      |
      |+# If compile.h exists already and we don't own autoconf.h
      |+# (i.e. we're not the same user who did make *config), don't
      |+# modify compile.h
      |+# So "sudo make install" won't change the "compiled by <user>"
      |+# do "compiled by root"
      |+
      |+if [ -r $TARGET -a ! -O ../include/linux/autoconf.h ]; then
      |+  echo ' (not modified)'
      |+  exit 0
      |+fi
      |+
      | if [ -r ../.version ]; then
      |   VERSION=`cat ../.version`
      | else
      
      The 'make bzImage && sudo make install' problem no longer happens
      because commit 1648e4f8 ("x86, kbuild: make "make install" not
      depend on vmlinux") fixed the root cause.
      
      Commit 19514fc6 ("arm, kbuild: make "make install" not depend on
      vmlinux") fixed the similar issue on ARM, with detailed explanation.
      
      So, the rule is that the installation targets should never trigger
      the builds of any build artifact. By following it, this check is
      unneeded.
      Signed-off-by: default avatarMasahiro Yamada <masahiroy@kernel.org>
      f84fdf8d
  2. 01 Mar, 2020 5 commits
  3. 29 Feb, 2020 4 commits
    • Dan Carpenter's avatar
      ext4: potential crash on allocation error in ext4_alloc_flex_bg_array() · 37b0b6b8
      Dan Carpenter authored
      If sbi->s_flex_groups_allocated is zero and the first allocation fails
      then this code will crash.  The problem is that "i--" will set "i" to
      -1 but when we compare "i >= sbi->s_flex_groups_allocated" then the -1
      is type promoted to unsigned and becomes UINT_MAX.  Since UINT_MAX
      is more than zero, the condition is true so we call kvfree(new_groups[-1]).
      The loop will carry on freeing invalid memory until it crashes.
      
      Fixes: 7c990728 ("ext4: fix potential race between s_flex_groups online resizing and access")
      Reviewed-by: default avatarSuraj Jitindar Singh <surajjs@amazon.com>
      Signed-off-by: default avatarDan Carpenter <dan.carpenter@oracle.com>
      Cc: stable@kernel.org
      Link: https://lore.kernel.org/r/20200228092142.7irbc44yaz3by7nb@kili.mountainSigned-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
      37b0b6b8
    • Wolfram Sang's avatar
      macintosh: therm_windtunnel: fix regression when instantiating devices · 38b17afb
      Wolfram Sang authored
      Removing attach_adapter from this driver caused a regression for at
      least some machines. Those machines had the sensors described in their
      DT, too, so they didn't need manual creation of the sensor devices. The
      old code worked, though, because manual creation came first. Creation of
      DT devices then failed later and caused error logs, but the sensors
      worked nonetheless because of the manually created devices.
      
      When removing attach_adaper, manual creation now comes later and loses
      the race. The sensor devices were already registered via DT, yet with
      another binding, so the driver could not be bound to it.
      
      This fix refactors the code to remove the race and only manually creates
      devices if there are no DT nodes present. Also, the DT binding is updated
      to match both, the DT and manually created devices. Because we don't
      know which device creation will be used at runtime, the code to start
      the kthread is moved to do_probe() which will be called by both methods.
      
      Fixes: 3e7bed52 ("macintosh: therm_windtunnel: drop using attach_adapter")
      Link: https://bugzilla.kernel.org/show_bug.cgi?id=201723Reported-by: default avatarErhard Furtner <erhard_f@mailbox.org>
      Tested-by: default avatarErhard Furtner <erhard_f@mailbox.org>
      Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
      Signed-off-by: default avatarWolfram Sang <wsa@the-dreams.de>
      Cc: stable@kernel.org # v4.19+
      38b17afb
    • Qian Cai's avatar
      jbd2: fix data races at struct journal_head · 6c5d9112
      Qian Cai authored
      journal_head::b_transaction and journal_head::b_next_transaction could
      be accessed concurrently as noticed by KCSAN,
      
       LTP: starting fsync04
       /dev/zero: Can't open blockdev
       EXT4-fs (loop0): mounting ext3 file system using the ext4 subsystem
       EXT4-fs (loop0): mounted filesystem with ordered data mode. Opts: (null)
       ==================================================================
       BUG: KCSAN: data-race in __jbd2_journal_refile_buffer [jbd2] / jbd2_write_access_granted [jbd2]
      
       write to 0xffff99f9b1bd0e30 of 8 bytes by task 25721 on cpu 70:
        __jbd2_journal_refile_buffer+0xdd/0x210 [jbd2]
        __jbd2_journal_refile_buffer at fs/jbd2/transaction.c:2569
        jbd2_journal_commit_transaction+0x2d15/0x3f20 [jbd2]
        (inlined by) jbd2_journal_commit_transaction at fs/jbd2/commit.c:1034
        kjournald2+0x13b/0x450 [jbd2]
        kthread+0x1cd/0x1f0
        ret_from_fork+0x27/0x50
      
       read to 0xffff99f9b1bd0e30 of 8 bytes by task 25724 on cpu 68:
        jbd2_write_access_granted+0x1b2/0x250 [jbd2]
        jbd2_write_access_granted at fs/jbd2/transaction.c:1155
        jbd2_journal_get_write_access+0x2c/0x60 [jbd2]
        __ext4_journal_get_write_access+0x50/0x90 [ext4]
        ext4_mb_mark_diskspace_used+0x158/0x620 [ext4]
        ext4_mb_new_blocks+0x54f/0xca0 [ext4]
        ext4_ind_map_blocks+0xc79/0x1b40 [ext4]
        ext4_map_blocks+0x3b4/0x950 [ext4]
        _ext4_get_block+0xfc/0x270 [ext4]
        ext4_get_block+0x3b/0x50 [ext4]
        __block_write_begin_int+0x22e/0xae0
        __block_write_begin+0x39/0x50
        ext4_write_begin+0x388/0xb50 [ext4]
        generic_perform_write+0x15d/0x290
        ext4_buffered_write_iter+0x11f/0x210 [ext4]
        ext4_file_write_iter+0xce/0x9e0 [ext4]
        new_sync_write+0x29c/0x3b0
        __vfs_write+0x92/0xa0
        vfs_write+0x103/0x260
        ksys_write+0x9d/0x130
        __x64_sys_write+0x4c/0x60
        do_syscall_64+0x91/0xb05
        entry_SYSCALL_64_after_hwframe+0x49/0xbe
      
       5 locks held by fsync04/25724:
        #0: ffff99f9911093f8 (sb_writers#13){.+.+}, at: vfs_write+0x21c/0x260
        #1: ffff99f9db4c0348 (&sb->s_type->i_mutex_key#15){+.+.}, at: ext4_buffered_write_iter+0x65/0x210 [ext4]
        #2: ffff99f5e7dfcf58 (jbd2_handle){++++}, at: start_this_handle+0x1c1/0x9d0 [jbd2]
        #3: ffff99f9db4c0168 (&ei->i_data_sem){++++}, at: ext4_map_blocks+0x176/0x950 [ext4]
        #4: ffffffff99086b40 (rcu_read_lock){....}, at: jbd2_write_access_granted+0x4e/0x250 [jbd2]
       irq event stamp: 1407125
       hardirqs last  enabled at (1407125): [<ffffffff980da9b7>] __find_get_block+0x107/0x790
       hardirqs last disabled at (1407124): [<ffffffff980da8f9>] __find_get_block+0x49/0x790
       softirqs last  enabled at (1405528): [<ffffffff98a0034c>] __do_softirq+0x34c/0x57c
       softirqs last disabled at (1405521): [<ffffffff97cc67a2>] irq_exit+0xa2/0xc0
      
       Reported by Kernel Concurrency Sanitizer on:
       CPU: 68 PID: 25724 Comm: fsync04 Tainted: G L 5.6.0-rc2-next-20200221+ #7
       Hardware name: HPE ProLiant DL385 Gen10/ProLiant DL385 Gen10, BIOS A40 07/10/2019
      
      The plain reads are outside of jh->b_state_lock critical section which result
      in data races. Fix them by adding pairs of READ|WRITE_ONCE().
      Reviewed-by: default avatarJan Kara <jack@suse.cz>
      Signed-off-by: default avatarQian Cai <cai@lca.pw>
      Link: https://lore.kernel.org/r/20200222043111.2227-1-cai@lca.pwSigned-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
      6c5d9112
    • Linus Torvalds's avatar
      Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi · 7557c1b3
      Linus Torvalds authored
      Pull SCSI fixes from James Bottomley:
       "Four small fixes.
      
        Three are in drivers for fairly obvious bugs. The fourth is a set of
        regressions introduced by the compat_ioctl changes because some of the
        compat updates wrongly replaced .ioctl instead of .compat_ioctl"
      
      * tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
        scsi: compat_ioctl: cdrom: Replace .ioctl with .compat_ioctl in four appropriate places
        scsi: zfcp: fix wrong data and display format of SFP+ temperature
        scsi: sd_sbc: Fix sd_zbc_report_zones()
        scsi: libfc: free response frame from GPN_ID
      7557c1b3
  4. 28 Feb, 2020 21 commits
  5. 27 Feb, 2020 6 commits