1. 03 3月, 2020 3 次提交
    • M
      kbuild: use KBUILD_DEFCONFIG as the fallback for DEFCONFIG_LIST · 2a86f661
      Masahiro Yamada 提交于
      Most of the Kconfig commands (except defconfig and all*config) read
      the .config file as a base set of CONFIG options.
      
      When it does not exist, the files in DEFCONFIG_LIST are searched in
      this order and loaded if found.
      
      I do not see much sense in the last two lines in DEFCONFIG_LIST.
      
      [1] ARCH_DEFCONFIG
      
      The entry for DEFCONFIG_LIST is guarded by 'depends on !UML'. So, the
      ARCH_DEFCONFIG definition in arch/x86/um/Kconfig is meaningless.
      
      arch/{sh,sparc,x86}/Kconfig define ARCH_DEFCONFIG depending on 32 or
      64 bit variant symbols. This is a little bit strange; ARCH_DEFCONFIG
      should be a fixed string because the base config file is loaded before
      the symbol evaluation stage.
      
      Using KBUILD_DEFCONFIG makes more sense because it is fixed before
      Kconfig is invoked. Fortunately, arch/{sh,sparc,x86}/Makefile define it
      in the same way, and it works as expected. Hence, replace ARCH_DEFCONFIG
      with "arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG)".
      
      [2] arch/$(ARCH)/defconfig
      
      This file path is no longer valid. The defconfig files are always located
      in the arch configs/ directories.
      
        $ find arch -name defconfig | sort
        arch/alpha/configs/defconfig
        arch/arm64/configs/defconfig
        arch/csky/configs/defconfig
        arch/nds32/configs/defconfig
        arch/riscv/configs/defconfig
        arch/s390/configs/defconfig
        arch/unicore32/configs/defconfig
      
      The path arch/*/configs/defconfig is already covered by
      "arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG)". So, this file path is
      not necessary.
      
      I moved the default KBUILD_DEFCONFIG to the top Makefile. Otherwise,
      the 7 architectures listed above would end up with endless loop of
      syncconfig.
      Signed-off-by: NMasahiro Yamada <masahiroy@kernel.org>
      2a86f661
    • N
      Documentation/llvm: add documentation on building w/ Clang/LLVM · fcf1b6a3
      Nick Desaulniers 提交于
      Added to kbuild documentation. Provides more official info on building
      kernels with Clang and LLVM than our wiki.
      Suggested-by: NKees Cook <keescook@chromium.org>
      Reviewed-by: NKees Cook <keescook@chromium.org>
      Reviewed-by: NNathan Chancellor <natechancellor@gmail.com>
      Reviewed-by: NSedat Dilek <sedat.dilek@gmail.com>
      Signed-off-by: NNick Desaulniers <ndesaulniers@google.com>
      Signed-off-by: NMasahiro Yamada <masahiroy@kernel.org>
      fcf1b6a3
    • M
      kbuild: remove trailing slash from devicetree/binding/ for descending · a1af8d71
      Masahiro Yamada 提交于
      obj-* needs a trailing slash for a directory, but subdir-* does not
      because it already implies a directory.
      
      Also, change subdir-y to subdir- to ensure this is effective only
      for cleaning targets.
      
      This makes the cleaning log consistent. (no trailing slash)
      
      Before:
      
        $ make clean
        CLEAN   Documentation/devicetree/bindings/
      
      After:
      
        $ make clean
        CLEAN   Documentation/devicetree/bindings
      Signed-off-by: NMasahiro Yamada <masahiroy@kernel.org>
      a1af8d71
  2. 02 3月, 2020 8 次提交
    • M
      fixdep: remove redundant null character check · 3f9070a6
      Masahiro Yamada 提交于
      If *q is '\0', the condition (isalnum(*q) || *q == '_') is false anyway.
      
      It is redundant to ensure non-zero *q.
      Signed-off-by: NMasahiro Yamada <masahiroy@kernel.org>
      3f9070a6
    • M
      fixdep: remove unneeded code and comments about *.ver files · 87d660f0
      Masahiro Yamada 提交于
      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: NMasahiro Yamada <masahiroy@kernel.org>
      87d660f0
    • M
      kbuild: remove cc-option switch from -Wframe-larger-than= · a83e4ca2
      Masahiro Yamada 提交于
      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: NMasahiro Yamada <masahiroy@kernel.org>
      Reviewed-by: NNathan Chancellor <natechancellor@gmail.com>
      Reviewed-by: NNick Desaulniers <ndesaulniers@google.com>
      a83e4ca2
    • M
      kbuild: remove the owner check in mkcompile_h · f84fdf8d
      Masahiro Yamada 提交于
      This reverts a very old commit, which dates back to the pre-git era:
      
      |commit 5d1cfb5b12f72145d30ba0f53c9f238144b122b8
      |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: NMasahiro Yamada <masahiroy@kernel.org>
      f84fdf8d
    • L
      Linux 5.6-rc4 · 98d54f81
      Linus Torvalds 提交于
      98d54f81
    • L
      Merge tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 · e7086982
      Linus Torvalds 提交于
      Pull ext4 fixes from Ted Ts'o:
       "Two more bug fixes (including a regression) for 5.6"
      
      * tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
        ext4: potential crash on allocation error in ext4_alloc_flex_bg_array()
        jbd2: fix data races at struct journal_head
      e7086982
    • L
      Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm · f853ed90
      Linus Torvalds 提交于
      Pull KVM fixes from Paolo Bonzini:
       "More bugfixes, including a few remaining "make W=1" issues such as too
        large frame sizes on some configurations.
      
        On the ARM side, the compiler was messing up shadow stacks between EL1
        and EL2 code, which is easily fixed with __always_inline"
      
      * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
        KVM: VMX: check descriptor table exits on instruction emulation
        kvm: x86: Limit the number of "kvm: disabled by bios" messages
        KVM: x86: avoid useless copy of cpufreq policy
        KVM: allow disabling -Werror
        KVM: x86: allow compiling as non-module with W=1
        KVM: Pre-allocate 1 cpumask variable per cpu for both pv tlb and pv ipis
        KVM: Introduce pv check helpers
        KVM: let declaration of kvm_get_running_vcpus match implementation
        KVM: SVM: allocate AVIC data structures based on kvm_amd module parameter
        arm64: Ask the compiler to __always_inline functions used by KVM at HYP
        KVM: arm64: Define our own swab32() to avoid a uapi static inline
        KVM: arm64: Ask the compiler to __always_inline functions used at HYP
        kvm: arm/arm64: Fold VHE entry/exit work into kvm_vcpu_run_vhe()
        KVM: arm/arm64: Fix up includes for trace.h
      f853ed90
    • O
      KVM: VMX: check descriptor table exits on instruction emulation · 86f7e90c
      Oliver Upton 提交于
      KVM emulates UMIP on hardware that doesn't support it by setting the
      'descriptor table exiting' VM-execution control and performing
      instruction emulation. When running nested, this emulation is broken as
      KVM refuses to emulate L2 instructions by default.
      
      Correct this regression by allowing the emulation of descriptor table
      instructions if L1 hasn't requested 'descriptor table exiting'.
      
      Fixes: 07721fee ("KVM: nVMX: Don't emulate instructions in guest mode")
      Reported-by: NJan Kiszka <jan.kiszka@web.de>
      Cc: stable@vger.kernel.org
      Cc: Paolo Bonzini <pbonzini@redhat.com>
      Cc: Jim Mattson <jmattson@google.com>
      Signed-off-by: NOliver Upton <oupton@google.com>
      Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      86f7e90c
  3. 01 3月, 2020 4 次提交
    • L
      Merge branch 'i2c/for-current-fixed' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux · fb279f4e
      Linus Torvalds 提交于
      Pull i2c fixes from Wolfram Sang:
       "I2C has three driver bugfixes for you. We agreed on the Mac regression
        to go in via I2C"
      
      * 'i2c/for-current-fixed' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
        macintosh: therm_windtunnel: fix regression when instantiating devices
        i2c: altera: Fix potential integer overflow
        i2c: jz4780: silence log flood on txabrt
      fb279f4e
    • D
      ext4: potential crash on allocation error in ext4_alloc_flex_bg_array() · 37b0b6b8
      Dan Carpenter 提交于
      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: NSuraj Jitindar Singh <surajjs@amazon.com>
      Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
      Cc: stable@kernel.org
      Link: https://lore.kernel.org/r/20200228092142.7irbc44yaz3by7nb@kili.mountainSigned-off-by: NTheodore Ts'o <tytso@mit.edu>
      37b0b6b8
    • W
      macintosh: therm_windtunnel: fix regression when instantiating devices · 38b17afb
      Wolfram Sang 提交于
      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: NErhard Furtner <erhard_f@mailbox.org>
      Tested-by: NErhard Furtner <erhard_f@mailbox.org>
      Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
      Signed-off-by: NWolfram Sang <wsa@the-dreams.de>
      Cc: stable@kernel.org # v4.19+
      38b17afb
    • Q
      jbd2: fix data races at struct journal_head · 6c5d9112
      Qian Cai 提交于
      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: NJan Kara <jack@suse.cz>
      Signed-off-by: NQian Cai <cai@lca.pw>
      Link: https://lore.kernel.org/r/20200222043111.2227-1-cai@lca.pwSigned-off-by: NTheodore Ts'o <tytso@mit.edu>
      6c5d9112
  4. 29 2月, 2020 8 次提交
  5. 28 2月, 2020 17 次提交