1. 10 Feb, 2015 3 commits
    • Mark Rutland's avatar
      arm64: Fix up /proc/cpuinfo · 33285ead
      Mark Rutland authored
      commit 44b82b77 upstream.
      
      [backport to 3.16.x: fold in missing MIDR_EL1 recording]
      
      Commit d7a49086 (arm64: cpuinfo: print info for all CPUs)
      attempted to clean up /proc/cpuinfo, but due to concerns regarding
      further changes was reverted in commit 5e39977e (Revert "arm64:
      cpuinfo: print info for all CPUs").
      
      There are two major issues with the arm64 /proc/cpuinfo format
      currently:
      
      * The "Features" line describes (only) the 64-bit hwcaps, which is
        problematic for some 32-bit applications which attempt to parse it. As
        the same names are used for analogous ISA features (e.g. aes) despite
        these generally being architecturally unrelated, it is not possible to
        simply append the 64-bit and 32-bit hwcaps in a manner that might not
        be misleading to some applications.
      
        Various potential solutions have appeared in vendor kernels. Typically
        the format of the Features line varies depending on whether the task
        is 32-bit.
      
      * Information is only printed regarding a single CPU. This does not
        match the ARM format, and does not provide sufficient information in
        big.LITTLE systems where CPUs are heterogeneous. The CPU information
        printed is queried from the current CPU's registers, which is racy
        w.r.t. cross-cpu migration.
      
      This patch attempts to solve these issues. The following changes are
      made:
      
      * When a task with a LINUX32 personality attempts to read /proc/cpuinfo,
        the "Features" line contains the decoded 32-bit hwcaps, as with the
        arm port. Otherwise, the decoded 64-bit hwcaps are shown. This aligns
        with the behaviour of COMPAT_UTS_MACHINE and COMPAT_ELF_PLATFORM. In
        the absense of compat support, the Features line is empty.
      
        The set of hwcaps injected into a task's auxval are unaffected.
      
      * Properties are printed per-cpu, as with the ARM port. The per-cpu
        information is queried from pre-recorded cpu information (as used by
        the sanity checks).
      
      * As with the previous attempt at fixing up /proc/cpuinfo, the hardware
        field is removed. The only users so far are 32-bit applications tied
        to particular boards, so no portable applications should be affected,
        and this should prevent future tying to particular boards.
      
      The following differences remain:
      
      * No model_name is printed, as this cannot be queried from the hardware
        and cannot be provided in a stable fashion. Use of the CPU
        {implementor,variant,part,revision} fields is sufficient to identify a
        CPU and is portable across arm and arm64.
      
      * The following system-wide properties are not provided, as they are not
        possible to provide generally. Programs relying on these are already
        tied to particular (32-bit only) boards:
        - Hardware
        - Revision
        - Serial
      
      No software has yet been identified for which these remaining
      differences are problematic.
      
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Will Deacon <will.deacon@arm.com>
      Cc: Ian Campbell <ijc@hellion.org.uk>
      Signed-off-by: default avatarMark Rutland <mark.rutland@arm.com>
      [Mark: backport to v3.16.x]
      Signed-off-by: default avatarLuis Henriques <luis.henriques@canonical.com>
      33285ead
    • Richard Guy Briggs's avatar
      powerpc: add little endian flag to syscall_get_arch() · b5746f2f
      Richard Guy Briggs authored
      commit 63f13448 upstream.
      
      Since both ppc and ppc64 have LE variants which are now reported by uname, add
      that flag (__AUDIT_ARCH_LE) to syscall_get_arch() and add AUDIT_ARCH_PPC64LE
      variant.
      
      Without this,  perf trace and auditctl fail.
      
      Mainline kernel reports ppc64le (per a0588015) but there is no matching
      AUDIT_ARCH_PPC64LE.
      
      Since 32-bit PPC LE is not supported by audit, don't advertise it in
      AUDIT_ARCH_PPC* variants.
      
      See:
      	https://www.redhat.com/archives/linux-audit/2014-August/msg00082.html
      	https://www.redhat.com/archives/linux-audit/2014-December/msg00004.htmlSigned-off-by: default avatarRichard Guy Briggs <rgb@redhat.com>
      Acked-by: default avatarPaul Moore <paul@paul-moore.com>
      Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
      [bwh: Backported to 3.16: arch is passed in by do_syscall_trace_enter()
       rather than queried by calling syscall_get_arch()]
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      Tested-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
      Signed-off-by: default avatarLuis Henriques <luis.henriques@canonical.com>
      b5746f2f
    • Luis Henriques's avatar
      Linux 3.16.7-ckt6 · 4ba6745b
      Luis Henriques authored
      Signed-off-by: default avatarLuis Henriques <luis.henriques@canonical.com>
      4ba6745b
  2. 04 Feb, 2015 37 commits