1. 22 Jan, 2019 1 commit
    • Paul Burton's avatar
      kbuild: Disable LD_DEAD_CODE_DATA_ELIMINATION with ftrace & GCC <= 4.7 · f20e6ccb
      Paul Burton authored
      commit 16fd20aa upstream.
      
      When building using GCC 4.7 or older, -ffunction-sections & the -pg flag
      used by ftrace are incompatible. This causes warnings or build failures
      (where -Werror applies) such as the following:
      
        arch/mips/generic/init.c:
          error: -ffunction-sections disabled; it makes profiling impossible
      
      This used to be taken into account by the ordering of calls to cc-option
      from within the top-level Makefile, which was introduced by commit
      90ad4052 ("kbuild: avoid conflict between -ffunction-sections and
      -pg on gcc-4.7"). Unfortunately this was broken when the
      CONFIG_LD_DEAD_CODE_DATA_ELIMINATION cc-option check was moved to
      Kconfig in commit e85d1d65 ("kbuild: test dead code/data elimination
      support in Kconfig"), because the flags used by this check no longer
      include -pg.
      
      Fix this by not allowing CONFIG_LD_DEAD_CODE_DATA_ELIMINATION to be
      enabled at the same time as ftrace/CONFIG_FUNCTION_TRACER when building
      using GCC 4.7 or older.
      Signed-off-by: 's avatarPaul Burton <paul.burton@mips.com>
      Fixes: e85d1d65 ("kbuild: test dead code/data elimination support in Kconfig")
      Reported-by: 's avatarGeert Uytterhoeven <geert@linux-m68k.org>
      Cc: Nicholas Piggin <npiggin@gmail.com>
      Cc: stable@vger.kernel.org # v4.19+
      Signed-off-by: 's avatarMasahiro Yamada <yamada.masahiro@socionext.com>
      Signed-off-by: 's avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      f20e6ccb
  2. 14 Dec, 2018 1 commit
  3. 30 Nov, 2018 2 commits
    • Li Zhijian's avatar
      initramfs: clean old path before creating a hardlink · 7c0950d4
      Li Zhijian authored
      sys_link() can fail due to the new path already existing.  This case
      ofen occurs when we use a concated initrd, for example:
      
      1) prepare a basic rootfs, it contains a regular files rc.local
      lizhijian@:~/yocto-tiny-i386-2016-04-22$ cat etc/rc.local
       #!/bin/sh
       echo "Running /etc/rc.local..."
      yocto-tiny-i386-2016-04-22$ find . | sed 's,^\./,,' | cpio -o -H newc | gzip -n -9 >../rootfs.cgz
      
      2) create a extra initrd which also includes a etc/rc.local
      lizhijian@:~/lkp-x86_64/etc$ echo "append initrd" >rc.local
      lizhijian@:~/lkp/lkp-x86_64/etc$ cat rc.local
      append initrd
      lizhijian@:~/lkp/lkp-x86_64/etc$ ln rc.local rc.local.hardlink
      append initrd
      lizhijian@:~/lkp/lkp-x86_64/etc$ stat rc.local rc.local.hardlink
        File: 'rc.local'
        Size: 14        	Blocks: 8          IO Block: 4096   regular file
      Device: 801h/2049d	Inode: 11296086    Links: 2
      Access: (0664/-rw-rw-r--)  Uid: ( 1002/lizhijian)   Gid: ( 1002/lizhijian)
      Access: 2018-11-15 16:08:28.654464815 +0800
      Modify: 2018-11-15 16:07:57.514903210 +0800
      Change: 2018-11-15 16:08:24.180228872 +0800
       Birth: -
        File: 'rc.local.hardlink'
        Size: 14        	Blocks: 8          IO Block: 4096   regular file
      Device: 801h/2049d	Inode: 11296086    Links: 2
      Access: (0664/-rw-rw-r--)  Uid: ( 1002/lizhijian)   Gid: ( 1002/lizhijian)
      Access: 2018-11-15 16:08:28.654464815 +0800
      Modify: 2018-11-15 16:07:57.514903210 +0800
      Change: 2018-11-15 16:08:24.180228872 +0800
       Birth: -
      
      lizhijian@:~/lkp/lkp-x86_64$ find . | sed 's,^\./,,' | cpio -o -H newc | gzip -n -9 >../rc-local.cgz
      lizhijian@:~/lkp/lkp-x86_64$ gzip -dc ../rc-local.cgz | cpio -t
      .
      etc
      etc/rc.local.hardlink <<< it will be extracted first at this initrd
      etc/rc.local
      
      3) concate 2 initrds and boot
      lizhijian@:~/lkp$ cat rootfs.cgz rc-local.cgz >concate-initrd.cgz
      lizhijian@:~/lkp$ qemu-system-x86_64 -nographic -enable-kvm -cpu host -smp 1 -m 1024 -kernel ~/lkp/linux/arch/x86/boot/bzImage -append "console=ttyS0 earlyprint=ttyS0 ignore_loglevel" -initrd ./concate-initr.cgz -serial stdio -nodefaults
      
      In this case, sys_link(2) will fail and return -EEXIST, so we can only get
      the rc.local at rootfs.cgz instead of rc-local.cgz
      
      [akpm@linux-foundation.org: move code to avoid forward declaration]
      Link: http://lkml.kernel.org/r/1542352368-13299-1-git-send-email-lizhijian@cn.fujitsu.comSigned-off-by: 's avatarLi Zhijian <lizhijian@cn.fujitsu.com>
      Cc: Philip Li <philip.li@intel.com>
      Cc: Dominik Brodowski <linux@dominikbrodowski.net>
      Cc: Li Zhijian <zhijianx.li@intel.com>
      Cc: Al Viro <viro@zeniv.linux.org.uk>
      Signed-off-by: 's avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: 's avatarLinus Torvalds <torvalds@linux-foundation.org>
      7c0950d4
    • Johannes Weiner's avatar
      psi: make disabling/enabling easier for vendor kernels · e0c27447
      Johannes Weiner authored
      Mel Gorman reports a hackbench regression with psi that would prohibit
      shipping the suse kernel with it default-enabled, but he'd still like
      users to be able to opt in at little to no cost to others.
      
      With the current combination of CONFIG_PSI and the psi_disabled bool set
      from the commandline, this is a challenge.  Do the following things to
      make it easier:
      
      1. Add a config option CONFIG_PSI_DEFAULT_DISABLED that allows distros
         to enable CONFIG_PSI in their kernel but leave the feature disabled
         unless a user requests it at boot-time.
      
         To avoid double negatives, rename psi_disabled= to psi=.
      
      2. Make psi_disabled a static branch to eliminate any branch costs
         when the feature is disabled.
      
      In terms of numbers before and after this patch, Mel says:
      
      : The following is a comparision using CONFIG_PSI=n as a baseline against
      : your patch and a vanilla kernel
      :
      :                          4.20.0-rc4             4.20.0-rc4             4.20.0-rc4
      :                 kconfigdisable-v1r1                vanilla        psidisable-v1r1
      : Amean     1       1.3100 (   0.00%)      1.3923 (  -6.28%)      1.3427 (  -2.49%)
      : Amean     3       3.8860 (   0.00%)      4.1230 *  -6.10%*      3.8860 (  -0.00%)
      : Amean     5       6.8847 (   0.00%)      8.0390 * -16.77%*      6.7727 (   1.63%)
      : Amean     7       9.9310 (   0.00%)     10.8367 *  -9.12%*      9.9910 (  -0.60%)
      : Amean     12     16.6577 (   0.00%)     18.2363 *  -9.48%*     17.1083 (  -2.71%)
      : Amean     18     26.5133 (   0.00%)     27.8833 *  -5.17%*     25.7663 (   2.82%)
      : Amean     24     34.3003 (   0.00%)     34.6830 (  -1.12%)     32.0450 (   6.58%)
      : Amean     30     40.0063 (   0.00%)     40.5800 (  -1.43%)     41.5087 (  -3.76%)
      : Amean     32     40.1407 (   0.00%)     41.2273 (  -2.71%)     39.9417 (   0.50%)
      :
      : It's showing that the vanilla kernel takes a hit (as the bisection
      : indicated it would) and that disabling PSI by default is reasonably
      : close in terms of performance for this particular workload on this
      : particular machine so;
      
      Link: http://lkml.kernel.org/r/20181127165329.GA29728@cmpxchg.orgSigned-off-by: 's avatarJohannes Weiner <hannes@cmpxchg.org>
      Tested-by: Mel Gorman's avatarMel Gorman <mgorman@techsingularity.net>
      Reported-by: Mel Gorman's avatarMel Gorman <mgorman@techsingularity.net>
      Signed-off-by: 's avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: 's avatarLinus Torvalds <torvalds@linux-foundation.org>
      e0c27447
  4. 31 Oct, 2018 5 commits
    • Mike Rapoport's avatar
      memblock: stop using implicit alignment to SMP_CACHE_BYTES · 7e1c4e27
      Mike Rapoport authored
      When a memblock allocation APIs are called with align = 0, the alignment
      is implicitly set to SMP_CACHE_BYTES.
      
      Implicit alignment is done deep in the memblock allocator and it can
      come as a surprise.  Not that such an alignment would be wrong even
      when used incorrectly but it is better to be explicit for the sake of
      clarity and the prinicple of the least surprise.
      
      Replace all such uses of memblock APIs with the 'align' parameter
      explicitly set to SMP_CACHE_BYTES and stop implicit alignment assignment
      in the memblock internal allocation functions.
      
      For the case when memblock APIs are used via helper functions, e.g.  like
      iommu_arena_new_node() in Alpha, the helper functions were detected with
      Coccinelle's help and then manually examined and updated where
      appropriate.
      
      The direct memblock APIs users were updated using the semantic patch below:
      
      @@
      expression size, min_addr, max_addr, nid;
      @@
      (
      |
      - memblock_alloc_try_nid_raw(size, 0, min_addr, max_addr, nid)
      + memblock_alloc_try_nid_raw(size, SMP_CACHE_BYTES, min_addr, max_addr,
      nid)
      |
      - memblock_alloc_try_nid_nopanic(size, 0, min_addr, max_addr, nid)
      + memblock_alloc_try_nid_nopanic(size, SMP_CACHE_BYTES, min_addr, max_addr,
      nid)
      |
      - memblock_alloc_try_nid(size, 0, min_addr, max_addr, nid)
      + memblock_alloc_try_nid(size, SMP_CACHE_BYTES, min_addr, max_addr, nid)
      |
      - memblock_alloc(size, 0)
      + memblock_alloc(size, SMP_CACHE_BYTES)
      |
      - memblock_alloc_raw(size, 0)
      + memblock_alloc_raw(size, SMP_CACHE_BYTES)
      |
      - memblock_alloc_from(size, 0, min_addr)
      + memblock_alloc_from(size, SMP_CACHE_BYTES, min_addr)
      |
      - memblock_alloc_nopanic(size, 0)
      + memblock_alloc_nopanic(size, SMP_CACHE_BYTES)
      |
      - memblock_alloc_low(size, 0)
      + memblock_alloc_low(size, SMP_CACHE_BYTES)
      |
      - memblock_alloc_low_nopanic(size, 0)
      + memblock_alloc_low_nopanic(size, SMP_CACHE_BYTES)
      |
      - memblock_alloc_from_nopanic(size, 0, min_addr)
      + memblock_alloc_from_nopanic(size, SMP_CACHE_BYTES, min_addr)
      |
      - memblock_alloc_node(size, 0, nid)
      + memblock_alloc_node(size, SMP_CACHE_BYTES, nid)
      )
      
      [mhocko@suse.com: changelog update]
      [akpm@linux-foundation.org: coding-style fixes]
      [rppt@linux.ibm.com: fix missed uses of implicit alignment]
        Link: http://lkml.kernel.org/r/20181016133656.GA10925@rapoport-lnx
      Link: http://lkml.kernel.org/r/1538687224-17535-1-git-send-email-rppt@linux.vnet.ibm.comSigned-off-by: 's avatarMike Rapoport <rppt@linux.vnet.ibm.com>
      Suggested-by: 's avatarMichal Hocko <mhocko@suse.com>
      Acked-by: Paul Burton <paul.burton@mips.com>	[MIPS]
      Acked-by: Michael Ellerman <mpe@ellerman.id.au>	[powerpc]
      Acked-by: 's avatarMichal Hocko <mhocko@suse.com>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Chris Zankel <chris@zankel.net>
      Cc: Geert Uytterhoeven <geert@linux-m68k.org>
      Cc: Guan Xuetao <gxt@pku.edu.cn>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Matt Turner <mattst88@gmail.com>
      Cc: Michal Simek <monstr@monstr.eu>
      Cc: Richard Weinberger <richard@nod.at>
      Cc: Russell King <linux@armlinux.org.uk>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Tony Luck <tony.luck@intel.com>
      Signed-off-by: 's avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: 's avatarLinus Torvalds <torvalds@linux-foundation.org>
      7e1c4e27
    • Mike Rapoport's avatar
      mm: remove include/linux/bootmem.h · 57c8a661
      Mike Rapoport authored
      Move remaining definitions and declarations from include/linux/bootmem.h
      into include/linux/memblock.h and remove the redundant header.
      
      The includes were replaced with the semantic patch below and then
      semi-automated removal of duplicated '#include <linux/memblock.h>
      
      @@
      @@
      - #include <linux/bootmem.h>
      + #include <linux/memblock.h>
      
      [sfr@canb.auug.org.au: dma-direct: fix up for the removal of linux/bootmem.h]
        Link: http://lkml.kernel.org/r/20181002185342.133d1680@canb.auug.org.au
      [sfr@canb.auug.org.au: powerpc: fix up for removal of linux/bootmem.h]
        Link: http://lkml.kernel.org/r/20181005161406.73ef8727@canb.auug.org.au
      [sfr@canb.auug.org.au: x86/kaslr, ACPI/NUMA: fix for linux/bootmem.h removal]
        Link: http://lkml.kernel.org/r/20181008190341.5e396491@canb.auug.org.au
      Link: http://lkml.kernel.org/r/1536927045-23536-30-git-send-email-rppt@linux.vnet.ibm.comSigned-off-by: 's avatarMike Rapoport <rppt@linux.vnet.ibm.com>
      Signed-off-by: 's avatarStephen Rothwell <sfr@canb.auug.org.au>
      Acked-by: 's avatarMichal Hocko <mhocko@suse.com>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Chris Zankel <chris@zankel.net>
      Cc: "David S. Miller" <davem@davemloft.net>
      Cc: Geert Uytterhoeven <geert@linux-m68k.org>
      Cc: Greentime Hu <green.hu@gmail.com>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: Guan Xuetao <gxt@pku.edu.cn>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
      Cc: Jonas Bonn <jonas@southpole.se>
      Cc: Jonathan Corbet <corbet@lwn.net>
      Cc: Ley Foon Tan <lftan@altera.com>
      Cc: Mark Salter <msalter@redhat.com>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Matt Turner <mattst88@gmail.com>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Michal Simek <monstr@monstr.eu>
      Cc: Palmer Dabbelt <palmer@sifive.com>
      Cc: Paul Burton <paul.burton@mips.com>
      Cc: Richard Kuo <rkuo@codeaurora.org>
      Cc: Richard Weinberger <richard@nod.at>
      Cc: Rich Felker <dalias@libc.org>
      Cc: Russell King <linux@armlinux.org.uk>
      Cc: Serge Semin <fancer.lancer@gmail.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Tony Luck <tony.luck@intel.com>
      Cc: Vineet Gupta <vgupta@synopsys.com>
      Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
      Signed-off-by: 's avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: 's avatarLinus Torvalds <torvalds@linux-foundation.org>
      57c8a661
    • Mike Rapoport's avatar
      memblock: replace alloc_bootmem with memblock_alloc · 2a5bda5a
      Mike Rapoport authored
      The alloc_bootmem(size) is a shortcut for allocation of SMP_CACHE_BYTES
      aligned memory. When the align parameter of memblock_alloc() is 0, the
      alignment is implicitly set to SMP_CACHE_BYTES and thus alloc_bootmem(size)
      and memblock_alloc(size, 0) are equivalent.
      
      The conversion is done using the following semantic patch:
      
      @@
      expression size;
      @@
      - alloc_bootmem(size)
      + memblock_alloc(size, 0)
      
      Link: http://lkml.kernel.org/r/1536927045-23536-22-git-send-email-rppt@linux.vnet.ibm.comSigned-off-by: 's avatarMike Rapoport <rppt@linux.vnet.ibm.com>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Chris Zankel <chris@zankel.net>
      Cc: "David S. Miller" <davem@davemloft.net>
      Cc: Geert Uytterhoeven <geert@linux-m68k.org>
      Cc: Greentime Hu <green.hu@gmail.com>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: Guan Xuetao <gxt@pku.edu.cn>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
      Cc: Jonas Bonn <jonas@southpole.se>
      Cc: Jonathan Corbet <corbet@lwn.net>
      Cc: Ley Foon Tan <lftan@altera.com>
      Cc: Mark Salter <msalter@redhat.com>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Matt Turner <mattst88@gmail.com>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Michal Hocko <mhocko@suse.com>
      Cc: Michal Simek <monstr@monstr.eu>
      Cc: Palmer Dabbelt <palmer@sifive.com>
      Cc: Paul Burton <paul.burton@mips.com>
      Cc: Richard Kuo <rkuo@codeaurora.org>
      Cc: Richard Weinberger <richard@nod.at>
      Cc: Rich Felker <dalias@libc.org>
      Cc: Russell King <linux@armlinux.org.uk>
      Cc: Serge Semin <fancer.lancer@gmail.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Tony Luck <tony.luck@intel.com>
      Cc: Vineet Gupta <vgupta@synopsys.com>
      Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
      Signed-off-by: 's avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: 's avatarLinus Torvalds <torvalds@linux-foundation.org>
      2a5bda5a
    • Mike Rapoport's avatar
      memblock: remove _virt from APIs returning virtual address · eb31d559
      Mike Rapoport authored
      The conversion is done using
      
      sed -i 's@memblock_virt_alloc@memblock_alloc@g' \
      	$(git grep -l memblock_virt_alloc)
      
      Link: http://lkml.kernel.org/r/1536927045-23536-8-git-send-email-rppt@linux.vnet.ibm.comSigned-off-by: 's avatarMike Rapoport <rppt@linux.vnet.ibm.com>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Chris Zankel <chris@zankel.net>
      Cc: "David S. Miller" <davem@davemloft.net>
      Cc: Geert Uytterhoeven <geert@linux-m68k.org>
      Cc: Greentime Hu <green.hu@gmail.com>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: Guan Xuetao <gxt@pku.edu.cn>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
      Cc: Jonas Bonn <jonas@southpole.se>
      Cc: Jonathan Corbet <corbet@lwn.net>
      Cc: Ley Foon Tan <lftan@altera.com>
      Cc: Mark Salter <msalter@redhat.com>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Matt Turner <mattst88@gmail.com>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Michal Hocko <mhocko@suse.com>
      Cc: Michal Simek <monstr@monstr.eu>
      Cc: Palmer Dabbelt <palmer@sifive.com>
      Cc: Paul Burton <paul.burton@mips.com>
      Cc: Richard Kuo <rkuo@codeaurora.org>
      Cc: Richard Weinberger <richard@nod.at>
      Cc: Rich Felker <dalias@libc.org>
      Cc: Russell King <linux@armlinux.org.uk>
      Cc: Serge Semin <fancer.lancer@gmail.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Tony Luck <tony.luck@intel.com>
      Cc: Vineet Gupta <vgupta@synopsys.com>
      Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
      Signed-off-by: 's avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: 's avatarLinus Torvalds <torvalds@linux-foundation.org>
      eb31d559
    • Nikolaus Voss's avatar
      init/do_mounts.c: add root=PARTLABEL=<name> support · f027c34d
      Nikolaus Voss authored
      Support referencing the root partition label from GPT as argument
      to the root= option on the kernel command line in analogy to
      referencing the partition uuid as root=PARTUUID=<uuid>.
      
      Specifying the partition label instead of the uuid is often much
      easier, e.g. in embedded environments when there is an
      A/B rootfs partition scheme for interruptible firmware updates
      (i.e. rootfsA/ rootfsB).
      
      The partition label can be queried with the blkid command.
      
      Link: http://lkml.kernel.org/r/20180822060904.828E510665E@pc-niv.weinmann.comSigned-off-by: 's avatarNikolaus Voss <nikolaus.voss@loewensteinmedical.de>
      Reviewed-by: 's avatarAndrew Morton <akpm@linux-foundation.org>
      Cc: Dominik Brodowski <linux@dominikbrodowski.net>
      Cc: Sasha Levin <Alexander.Levin@microsoft.com>
      Cc: Al Viro <viro@zeniv.linux.org.uk>
      Cc: Jens Axboe <axboe@kernel.dk>
      Signed-off-by: 's avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: 's avatarLinus Torvalds <torvalds@linux-foundation.org>
      f027c34d
  5. 26 Oct, 2018 2 commits
  6. 09 Oct, 2018 1 commit
    • Martin Schwidefsky's avatar
      init: add arch_call_rest_init to allow stack switching · 53c99bd6
      Martin Schwidefsky authored
      With CONFIG_VMAP_STACK=y the kernel stack of all tasks should be
      allocated in the vmalloc space. The initial stack used for all
      the early init code is in the init_thread_union. To be able to
      switch from this early stack to a properly allocated stack
      from vmalloc the architecture needs a switch-over point.
      
      Introduce the arch_call_rest_init() function with a weak definition
      in init/main.c with the only purpose to call rest_init() from the
      end of start_kernel(). The architecture override can then do the
      necessary magic to switch to the new vmalloc'ed stack.
      Signed-off-by: 's avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
      53c99bd6
  7. 02 Oct, 2018 1 commit
  8. 27 Sep, 2018 1 commit
    • Ard Biesheuvel's avatar
      jump_label: Annotate entries that operate on __init code earlier · 19483677
      Ard Biesheuvel authored
      Jump table entries are mostly read-only, with the exception of the
      init and module loader code that defuses entries that point into init
      code when the code being referred to is freed.
      
      For robustness, it would be better to move these entries into the
      ro_after_init section, but clearing the 'code' member of each jump
      table entry referring to init code at module load time races with the
      module_enable_ro() call that remaps the ro_after_init section read
      only, so we'd like to do it earlier.
      
      So given that whether such an entry refers to init code can be decided
      much earlier, we can pull this check forward. Since we may still need
      the code entry at this point, let's switch to setting a low bit in the
      'key' member just like we do to annotate the default state of a jump
      table entry.
      Signed-off-by: 's avatarArd Biesheuvel <ard.biesheuvel@linaro.org>
      Signed-off-by: 's avatarThomas Gleixner <tglx@linutronix.de>
      Reviewed-by: 's avatarKees Cook <keescook@chromium.org>
      Acked-by: 's avatarPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: linux-arm-kernel@lists.infradead.org
      Cc: linux-s390@vger.kernel.org
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: Will Deacon <will.deacon@arm.com>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Jessica Yu <jeyu@kernel.org>
      Link: https://lkml.kernel.org/r/20180919065144.25010-8-ard.biesheuvel@linaro.org
      19483677
  9. 23 Aug, 2018 1 commit
  10. 22 Aug, 2018 5 commits
  11. 17 Aug, 2018 1 commit
  12. 12 Aug, 2018 1 commit
    • Linus Torvalds's avatar
      init: rename and re-order boot_cpu_state_init() · b5b1404d
      Linus Torvalds authored
      This is purely a preparatory patch for upcoming changes during the 4.19
      merge window.
      
      We have a function called "boot_cpu_state_init()" that isn't really
      about the bootup cpu state: that is done much earlier by the similarly
      named "boot_cpu_init()" (note lack of "state" in name).
      
      This function initializes some hotplug CPU state, and needs to run after
      the percpu data has been properly initialized.  It even has a comment to
      that effect.
      
      Except it _doesn't_ actually run after the percpu data has been properly
      initialized.  On x86 it happens to do that, but on at least arm and
      arm64, the percpu base pointers are initialized by the arch-specific
      'smp_prepare_boot_cpu()' hook, which ran _after_ boot_cpu_state_init().
      
      This had some unexpected results, and in particular we have a patch
      pending for the merge window that did the obvious cleanup of using
      'this_cpu_write()' in the cpu hotplug init code:
      
        -       per_cpu_ptr(&cpuhp_state, smp_processor_id())->state = CPUHP_ONLINE;
        +       this_cpu_write(cpuhp_state.state, CPUHP_ONLINE);
      
      which is obviously the right thing to do.  Except because of the
      ordering issue, it actually failed miserably and unexpectedly on arm64.
      
      So this just fixes the ordering, and changes the name of the function to
      be 'boot_cpu_hotplug_init()' to make it obvious that it's about cpu
      hotplug state, because the core CPU state was supposed to have already
      been done earlier.
      
      Marked for stable, since the (not yet merged) patch that will show this
      problem is marked for stable.
      Reported-by: 's avatarVlastimil Babka <vbabka@suse.cz>
      Reported-by: Mian Yousaf Kaukab's avatarMian Yousaf Kaukab <yousaf.kaukab@suse.com>
      Suggested-by: 's avatarCatalin Marinas <catalin.marinas@arm.com>
      Acked-by: 's avatarThomas Gleixner <tglx@linutronix.de>
      Cc: Will Deacon <will.deacon@arm.com>
      Cc: stable@kernel.org
      Signed-off-by: 's avatarLinus Torvalds <torvalds@linux-foundation.org>
      b5b1404d
  13. 10 Aug, 2018 1 commit
  14. 09 Aug, 2018 2 commits
    • Eric W. Biederman's avatar
      signal: Don't restart fork when signals come in. · c3ad2c3b
      Eric W. Biederman authored
      Wen Yang <wen.yang99@zte.com.cn> and majiang <ma.jiang@zte.com.cn>
      report that a periodic signal received during fork can cause fork to
      continually restart preventing an application from making progress.
      
      The code was being overly pessimistic.  Fork needs to guarantee that a
      signal sent to multiple processes is logically delivered before the
      fork and just to the forking process or logically delivered after the
      fork to both the forking process and it's newly spawned child.  For
      signals like periodic timers that are always delivered to a single
      process fork can safely complete and let them appear to logically
      delivered after the fork().
      
      While examining this issue I also discovered that fork today will miss
      signals delivered to multiple processes during the fork and handled by
      another thread.  Similarly the current code will also miss blocked
      signals that are delivered to multiple process, as those signals will
      not appear pending during fork.
      
      Add a list of each thread that is currently forking, and keep on that
      list a signal set that records all of the signals sent to multiple
      processes.  When fork completes initialize the new processes
      shared_pending signal set with it.  The calculate_sigpending function
      will see those signals and set TIF_SIGPENDING causing the new task to
      take the slow path to userspace to handle those signals.  Making it
      appear as if those signals were received immediately after the fork.
      
      It is not possible to send real time signals to multiple processes and
      exceptions don't go to multiple processes, which means that that are
      no signals sent to multiple processes that require siginfo.  This
      means it is safe to not bother collecting siginfo on signals sent
      during fork.
      
      The sigaction of a child of fork is initially the same as the
      sigaction of the parent process.  So a signal the parent ignores the
      child will also initially ignore.  Therefore it is safe to ignore
      signals sent to multiple processes and ignored by the forking process.
      
      Signals sent to only a single process or only a single thread and delivered
      during fork are treated as if they are received after the fork, and generally
      not dealt with.  They won't cause any problems.
      
      V2: Added removal from the multiprocess list on failure.
      V3: Use -ERESTARTNOINTR directly
      V4: - Don't queue both SIGCONT and SIGSTOP
          - Initialize signal_struct.multiprocess in init_task
          - Move setting of shared_pending to before the new task
            is visible to signals.  This prevents signals from comming
            in before shared_pending.signal is set to delayed.signal
            and being lost.
      V5: - rework list add and delete to account for idle threads
      v6: - Use sigdelsetmask when removing stop signals
      
      Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=200447
      Reported-by: Wen Yang <wen.yang99@zte.com.cn> and
      Reported-by: 's avatarmajiang <ma.jiang@zte.com.cn>
      Fixes: 4a2c7a78 ("[PATCH] make fork() atomic wrt pgrp/session signals")
      Signed-off-by: 's avatar"Eric W. Biederman" <ebiederm@xmission.com>
      c3ad2c3b
    • Rob Landley's avatar
      init/Kconfig: Use short unix-style option instead of --longname · 47f38ae0
      Rob Landley authored
      Avoids warning messages with the latest release of toybox, which never
      bothered to implement the --longopts nothing was using.
      Signed-off-by: 's avatarRob Landley <rob@landley.net>
      Signed-off-by: 's avatarMasahiro Yamada <yamada.masahiro@socionext.com>
      47f38ae0
  15. 01 Aug, 2018 3 commits
  16. 31 Jul, 2018 1 commit
    • Joel Fernandes (Google)'s avatar
      tracing: Centralize preemptirq tracepoints and unify their usage · c3bc8fd6
      Joel Fernandes (Google) authored
      This patch detaches the preemptirq tracepoints from the tracers and
      keeps it separate.
      
      Advantages:
      * Lockdep and irqsoff event can now run in parallel since they no longer
      have their own calls.
      
      * This unifies the usecase of adding hooks to an irqsoff and irqson
      event, and a preemptoff and preempton event.
        3 users of the events exist:
        - Lockdep
        - irqsoff and preemptoff tracers
        - irqs and preempt trace events
      
      The unification cleans up several ifdefs and makes the code in preempt
      tracer and irqsoff tracers simpler. It gets rid of all the horrific
      ifdeferry around PROVE_LOCKING and makes configuration of the different
      users of the tracepoints more easy and understandable. It also gets rid
      of the time_* function calls from the lockdep hooks used to call into
      the preemptirq tracer which is not needed anymore. The negative delta in
      lines of code in this patch is quite large too.
      
      In the patch we introduce a new CONFIG option PREEMPTIRQ_TRACEPOINTS
      as a single point for registering probes onto the tracepoints. With
      this,
      the web of config options for preempt/irq toggle tracepoints and its
      users becomes:
      
       PREEMPT_TRACER   PREEMPTIRQ_EVENTS  IRQSOFF_TRACER PROVE_LOCKING
             |                 |     \         |           |
             \    (selects)    /      \        \ (selects) /
            TRACE_PREEMPT_TOGGLE       ----> TRACE_IRQFLAGS
                            \                  /
                             \ (depends on)   /
                           PREEMPTIRQ_TRACEPOINTS
      
      Other than the performance tests mentioned in the previous patch, I also
      ran the locking API test suite. I verified that all tests cases are
      passing.
      
      I also injected issues by not registering lockdep probes onto the
      tracepoints and I see failures to confirm that the probes are indeed
      working.
      
      This series + lockdep probes not registered (just to inject errors):
      [    0.000000]      hard-irqs-on + irq-safe-A/21:  ok  |  ok  |  ok  |
      [    0.000000]      soft-irqs-on + irq-safe-A/21:  ok  |  ok  |  ok  |
      [    0.000000]        sirq-safe-A => hirqs-on/12:FAILED|FAILED|  ok  |
      [    0.000000]        sirq-safe-A => hirqs-on/21:FAILED|FAILED|  ok  |
      [    0.000000]          hard-safe-A + irqs-on/12:FAILED|FAILED|  ok  |
      [    0.000000]          soft-safe-A + irqs-on/12:FAILED|FAILED|  ok  |
      [    0.000000]          hard-safe-A + irqs-on/21:FAILED|FAILED|  ok  |
      [    0.000000]          soft-safe-A + irqs-on/21:FAILED|FAILED|  ok  |
      [    0.000000]     hard-safe-A + unsafe-B #1/123:  ok  |  ok  |  ok  |
      [    0.000000]     soft-safe-A + unsafe-B #1/123:  ok  |  ok  |  ok  |
      
      With this series + lockdep probes registered, all locking tests pass:
      
      [    0.000000]      hard-irqs-on + irq-safe-A/21:  ok  |  ok  |  ok  |
      [    0.000000]      soft-irqs-on + irq-safe-A/21:  ok  |  ok  |  ok  |
      [    0.000000]        sirq-safe-A => hirqs-on/12:  ok  |  ok  |  ok  |
      [    0.000000]        sirq-safe-A => hirqs-on/21:  ok  |  ok  |  ok  |
      [    0.000000]          hard-safe-A + irqs-on/12:  ok  |  ok  |  ok  |
      [    0.000000]          soft-safe-A + irqs-on/12:  ok  |  ok  |  ok  |
      [    0.000000]          hard-safe-A + irqs-on/21:  ok  |  ok  |  ok  |
      [    0.000000]          soft-safe-A + irqs-on/21:  ok  |  ok  |  ok  |
      [    0.000000]     hard-safe-A + unsafe-B #1/123:  ok  |  ok  |  ok  |
      [    0.000000]     soft-safe-A + unsafe-B #1/123:  ok  |  ok  |  ok  |
      
      Link: http://lkml.kernel.org/r/20180730222423.196630-4-joel@joelfernandes.orgAcked-by: 's avatarPeter Zijlstra (Intel) <peterz@infradead.org>
      Reviewed-by: 's avatarNamhyung Kim <namhyung@kernel.org>
      Signed-off-by: 's avatarJoel Fernandes (Google) <joel@joelfernandes.org>
      Signed-off-by: 's avatarSteven Rostedt (VMware) <rostedt@goodmis.org>
      c3bc8fd6
  17. 21 Jul, 2018 3 commits
    • Eric W. Biederman's avatar
      pid: Implement PIDTYPE_TGID · 6883f81a
      Eric W. Biederman authored
      Everywhere except in the pid array we distinguish between a tasks pid and
      a tasks tgid (thread group id).  Even in the enumeration we want that
      distinction sometimes so we have added __PIDTYPE_TGID.  With leader_pid
      we almost have an implementation of PIDTYPE_TGID in struct signal_struct.
      
      Add PIDTYPE_TGID as a first class member of the pid_type enumeration and
      into the pids array.  Then remove the __PIDTYPE_TGID special case and the
      leader_pid in signal_struct.
      
      The net size increase is just an extra pointer added to struct pid and
      an extra pair of pointers of an hlist_node added to task_struct.
      
      The effect on code maintenance is the removal of a number of special
      cases today and the potential to remove many more special cases as
      PIDTYPE_TGID gets used to it's fullest.  The long term potential
      is allowing zombie thread group leaders to exit, which will remove
      a lot more special cases in the code.
      Signed-off-by: 's avatar"Eric W. Biederman" <ebiederm@xmission.com>
      6883f81a
    • Eric W. Biederman's avatar
      pids: Move the pgrp and session pid pointers from task_struct to signal_struct · 2c470475
      Eric W. Biederman authored
      To access these fields the code always has to go to group leader so
      going to signal struct is no loss and is actually a fundamental simplification.
      
      This saves a little bit of memory by only allocating the pid pointer array
      once instead of once for every thread, and even better this removes a
      few potential races caused by the fact that group_leader can be changed
      by de_thread, while signal_struct can not.
      Signed-off-by: 's avatar"Eric W. Biederman" <ebiederm@xmission.com>
      2c470475
    • Eric W. Biederman's avatar
      pids: Initialize leader_pid in init_task · 2896b0f0
      Eric W. Biederman authored
      This is cheap and no cost so we might as well.
      Signed-off-by: 's avatar"Eric W. Biederman" <ebiederm@xmission.com>
      2896b0f0
  18. 19 Jul, 2018 3 commits
    • Joerg Roedel's avatar
      x86/mm/pti: Introduce pti_finalize() · b976690f
      Joerg Roedel authored
      Introduce a new function to finalize the kernel mappings for the userspace
      page-table after all ro/nx protections have been applied to the kernel
      mappings.
      
      Also move the call to pti_clone_kernel_text() to that function so that it
      will run on 32 bit kernels too.
      Signed-off-by: 's avatarJoerg Roedel <jroedel@suse.de>
      Signed-off-by: 's avatarThomas Gleixner <tglx@linutronix.de>
      Tested-by: Pavel Machek's avatarPavel Machek <pavel@ucw.cz>
      Cc: "H . Peter Anvin" <hpa@zytor.com>
      Cc: linux-mm@kvack.org
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Dave Hansen <dave.hansen@intel.com>
      Cc: Josh Poimboeuf <jpoimboe@redhat.com>
      Cc: Juergen Gross <jgross@suse.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Jiri Kosina <jkosina@suse.cz>
      Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: David Laight <David.Laight@aculab.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      Cc: Eduardo Valentin <eduval@amazon.com>
      Cc: Greg KH <gregkh@linuxfoundation.org>
      Cc: Will Deacon <will.deacon@arm.com>
      Cc: aliguori@amazon.com
      Cc: daniel.gruss@iaik.tugraz.at
      Cc: hughd@google.com
      Cc: keescook@google.com
      Cc: Andrea Arcangeli <aarcange@redhat.com>
      Cc: Waiman Long <llong@redhat.com>
      Cc: "David H . Gutteridge" <dhgutteridge@sympatico.ca>
      Cc: joro@8bytes.org
      Link: https://lkml.kernel.org/r/1531906876-13451-30-git-send-email-joro@8bytes.org
      b976690f
    • Pavel Tatashin's avatar
      sched/clock: Enable sched clock early · 857baa87
      Pavel Tatashin authored
      Allow sched_clock() to be used before schec_clock_init() is called.  This
      provides a way to get early boot timestamps on machines with unstable
      clocks.
      Signed-off-by: 's avatarPavel Tatashin <pasha.tatashin@oracle.com>
      Signed-off-by: 's avatarThomas Gleixner <tglx@linutronix.de>
      Cc: steven.sistare@oracle.com
      Cc: daniel.m.jordan@oracle.com
      Cc: linux@armlinux.org.uk
      Cc: schwidefsky@de.ibm.com
      Cc: heiko.carstens@de.ibm.com
      Cc: john.stultz@linaro.org
      Cc: sboyd@codeaurora.org
      Cc: hpa@zytor.com
      Cc: douly.fnst@cn.fujitsu.com
      Cc: peterz@infradead.org
      Cc: prarit@redhat.com
      Cc: feng.tang@intel.com
      Cc: pmladek@suse.com
      Cc: gnomes@lxorguk.ukuu.org.uk
      Cc: linux-s390@vger.kernel.org
      Cc: boris.ostrovsky@oracle.com
      Cc: jgross@suse.com
      Cc: pbonzini@redhat.com
      Link: https://lkml.kernel.org/r/20180719205545.16512-24-pasha.tatashin@oracle.com
      857baa87
    • Pavel Tatashin's avatar
      sched/clock: Move sched clock initialization and merge with generic clock · 5d2a4e91
      Pavel Tatashin authored
      sched_clock_postinit() initializes a generic clock on systems where no
      other clock is provided. This function may be called only after
      timekeeping_init().
      
      Rename sched_clock_postinit to generic_clock_inti() and call it from
      sched_clock_init(). Move the call for sched_clock_init() until after
      time_init().
      Suggested-by: 's avatarPeter Zijlstra <peterz@infradead.org>
      Signed-off-by: 's avatarPavel Tatashin <pasha.tatashin@oracle.com>
      Signed-off-by: 's avatarThomas Gleixner <tglx@linutronix.de>
      Cc: steven.sistare@oracle.com
      Cc: daniel.m.jordan@oracle.com
      Cc: linux@armlinux.org.uk
      Cc: schwidefsky@de.ibm.com
      Cc: heiko.carstens@de.ibm.com
      Cc: john.stultz@linaro.org
      Cc: sboyd@codeaurora.org
      Cc: hpa@zytor.com
      Cc: douly.fnst@cn.fujitsu.com
      Cc: prarit@redhat.com
      Cc: feng.tang@intel.com
      Cc: pmladek@suse.com
      Cc: gnomes@lxorguk.ukuu.org.uk
      Cc: linux-s390@vger.kernel.org
      Cc: boris.ostrovsky@oracle.com
      Cc: jgross@suse.com
      Cc: pbonzini@redhat.com
      Link: https://lkml.kernel.org/r/20180719205545.16512-23-pasha.tatashin@oracle.com
      5d2a4e91
  19. 17 Jul, 2018 1 commit
    • Laura Abbott's avatar
      kbuild: Add build salt to the kernel and modules · 9afb719e
      Laura Abbott authored
      In Fedora, the debug information is packaged separately (foo-debuginfo) and
      can be installed separately. There's been a long standing issue where only
      one version of a debuginfo info package can be installed at a time. There's
      been an effort for Fedora for parallel debuginfo to rectify this problem.
      
      Part of the requirement to allow parallel debuginfo to work is that build ids
      are unique between builds. The existing upstream rpm implementation ensures
      this by re-calculating the build-id using the version and release as a
      seed. This doesn't work 100% for the kernel because of the vDSO which is
      its own binary and doesn't get updated when embedded.
      
      Fix this by adding some data in an ELF note for both the kernel and modules.
      The data is controlled via a Kconfig option so distributions can set it
      to an appropriate value to ensure uniqueness between builds.
      Suggested-by: 's avatarMasahiro Yamada <yamada.masahiro@socionext.com>
      Signed-off-by: 's avatarLaura Abbott <labbott@redhat.com>
      Signed-off-by: 's avatarMasahiro Yamada <yamada.masahiro@socionext.com>
      9afb719e
  20. 28 Jun, 2018 1 commit
  21. 25 Jun, 2018 1 commit
  22. 14 Jun, 2018 1 commit
    • Christoph Hellwig's avatar
      dma-mapping: move all DMA mapping code to kernel/dma · cf65a0f6
      Christoph Hellwig authored
      Currently the code is split over various files with dma- prefixes in the
      lib/ and drives/base directories, and the number of files keeps growing.
      Move them into a single directory to keep the code together and remove
      the file name prefixes.  To match the irq infrastructure this directory
      is placed under the kernel/ directory.
      Signed-off-by: 's avatarChristoph Hellwig <hch@lst.de>
      cf65a0f6
  23. 08 Jun, 2018 1 commit