1. 14 Jun, 2018 5 commits
    • Andy Lutomirski's avatar
      x86/fpu: Default eagerfpu=on on all CPUs · 5982a1a8
      Andy Lutomirski authored
      We have eager and lazy FPU modes, introduced in:
      
        304bceda ("x86, fpu: use non-lazy fpu restore for processors supporting xsave")
      
      The result is rather messy.  There are two code paths in almost all
      of the FPU code, and only one of them (the eager case) is tested
      frequently, since most kernel developers have new enough hardware
      that we use eagerfpu.
      
      It seems that, on any remotely recent hardware, eagerfpu is a win:
      glibc uses SSE2, so laziness is probably overoptimistic, and, in any
      case, manipulating TS is far slower that saving and restoring the
      full state.  (Stores to CR0.TS are serializing and are poorly
      optimized.)
      
      To try to shake out any latent issues on old hardware, this changes
      the default to eager on all CPUs.  If no performance or functionality
      problems show up, a subsequent patch could remove lazy mode entirely.
      Signed-off-by: default avatarAndy Lutomirski <luto@kernel.org>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: Fenghua Yu <fenghua.yu@intel.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Oleg Nesterov <oleg@redhat.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com>
      Cc: Rik van Riel <riel@redhat.com>
      Cc: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: yu-cheng yu <yu-cheng.yu@intel.com>
      Link: http://lkml.kernel.org/r/ac290de61bf08d9cfc2664a4f5080257ffc1075a.1453675014.git.luto@kernel.orgSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      
      CVE-2018-3665 (x86)
      
      (cherry picked from commit 58122bf1)
      Signed-off-by: default avatarTyler Hicks <tyhicks@canonical.com>
      Signed-off-by: default avatarStefan Bader <stefan.bader@canonical.com>
      5982a1a8
    • yu-cheng yu's avatar
      x86/fpu: Disable MPX when eagerfpu is off · b42ae5ea
      yu-cheng yu authored
      This issue is a fallout from the command-line parsing move.
      
      When "eagerfpu=off" is given as a command-line input, the kernel
      should disable MPX support. The decision for turning off MPX was
      made in fpu__init_system_ctx_switch(), which is after the
      selection of the XSAVE format. This patch fixes it by getting
      that decision done earlier in fpu__init_system_xstate().
      Signed-off-by: default avatarYu-cheng Yu <yu-cheng.yu@intel.com>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Borislav Petkov <bp@suse.de>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: Fenghua Yu <fenghua.yu@intel.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Oleg Nesterov <oleg@redhat.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com>
      Cc: Ravi V. Shankar <ravi.v.shankar@intel.com>
      Cc: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: yu-cheng yu <yu-cheng.yu@intel.com>
      Link: http://lkml.kernel.org/r/1452119094-7252-4-git-send-email-yu-cheng.yu@intel.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      
      CVE-2018-3665 (x86)
      
      (backported from commit a5fe93a5)
      Signed-off-by: default avatarTyler Hicks <tyhicks@canonical.com>
      Signed-off-by: default avatarStefan Bader <stefan.bader@canonical.com>
      b42ae5ea
    • Andy Lutomirski's avatar
      x86/fpu: Fix 'no387' regression · f12c41e8
      Andy Lutomirski authored
      After fixing FPU option parsing, we now parse the 'no387' boot option
      too early: no387 clears X86_FEATURE_FPU before it's even probed, so
      the boot CPU promptly re-enables it.
      
      I suspect it gets even more confused on SMP.
      
      Fix the probing code to leave X86_FEATURE_FPU off if it's been
      disabled by setup_clear_cpu_cap().
      Signed-off-by: default avatarAndy Lutomirski <luto@kernel.org>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      Cc: Fenghua Yu <fenghua.yu@intel.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Oleg Nesterov <oleg@redhat.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com>
      Cc: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: yu-cheng yu <yu-cheng.yu@intel.com>
      Fixes: 4f81cbaf ("x86/fpu: Fix early FPU command-line parsing")
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      
      CVE-2018-3665 (x86)
      
      (cherry picked from commit f363938c)
      Signed-off-by: default avatarTyler Hicks <tyhicks@canonical.com>
      Signed-off-by: default avatarStefan Bader <stefan.bader@canonical.com>
      f12c41e8
    • yu-cheng yu's avatar
      x86/fpu: Fix early FPU command-line parsing · a5919965
      yu-cheng yu authored
      The function fpu__init_system() is executed before
      parse_early_param(). This causes wrong FPU configuration. This
      patch fixes this issue by parsing boot_command_line in the
      beginning of fpu__init_system().
      
      With all four patches in this series, each parameter disables
      features as the following:
      
      eagerfpu=off: eagerfpu, avx, avx2, avx512, mpx
      no387: fpu
      nofxsr: fxsr, fxsropt, xmm
      noxsave: xsave, xsaveopt, xsaves, xsavec, avx, avx2, avx512,
      mpx, xgetbv1 noxsaveopt: xsaveopt
      noxsaves: xsaves
      Signed-off-by: default avatarYu-cheng Yu <yu-cheng.yu@intel.com>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Borislav Petkov <bp@suse.de>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: Fenghua Yu <fenghua.yu@intel.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Oleg Nesterov <oleg@redhat.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com>
      Cc: Ravi V. Shankar <ravi.v.shankar@intel.com>
      Cc: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: yu-cheng yu <yu-cheng.yu@intel.com>
      Link: http://lkml.kernel.org/r/1452119094-7252-2-git-send-email-yu-cheng.yu@intel.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      
      CVE-2018-3665 (x86)
      
      (cherry picked from commit 4f81cbaf)
      Signed-off-by: default avatarTyler Hicks <tyhicks@canonical.com>
      Signed-off-by: default avatarStefan Bader <stefan.bader@canonical.com>
      a5919965
    • Stefan Bader's avatar
      UBUNTU: Start new release · 42de96b8
      Stefan Bader authored
      Ignore: yes
      Signed-off-by: default avatarStefan Bader <stefan.bader@canonical.com>
      42de96b8
  2. 12 Jun, 2018 1 commit
  3. 08 Jun, 2018 34 commits