1. 15 7月, 2008 2 次提交
  2. 14 7月, 2008 27 次提交
  3. 13 7月, 2008 3 次提交
  4. 12 7月, 2008 5 次提交
    • M
      x86: fix ldt limit for 64 bit · 5ac37f87
      Michael Karcher 提交于
      Fix size of LDT entries. On x86-64, ldt_desc is a double-sized descriptor.
      Signed-off-by: NMichael Karcher <kernel@mkarcher.dialup.fu-berlin.de>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      5ac37f87
    • G
      x86: merge dwarf2 headers · 392a0fc9
      Glauber Costa 提交于
      Merge dwarf2_32.h and dwarf2_64.h into dwarf2.h.
      Signed-off-by: NGlauber Costa <gcosta@redhat.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      392a0fc9
    • G
      x86: use AS_CFI instead of UNWIND_INFO · d73a731a
      Glauber Costa 提交于
      In dwarf2_32.h, test for CONFIG_AS_CFI instead of
      CONFIG_UNWIND_INFO. Turns out that searching for UNWIND_INFO
      returns no match in any Kconfig or Makefile, so we're really
      just throwing everything away regarding dwarf frames for i386.
      
      The test that generates CONFIG_AS_CFI does not have anything
      x86_64-specific, and right now, checking V=1 builds shows me
      that the flags is there anyway, although unused.
      Signed-off-by: NGlauber Costa <gcosta@redhat.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      d73a731a
    • G
      x86: use ignore macro instead of hash comment · 70f1bba4
      Glauber Costa 提交于
      In dwarf_64.h header, use the "ignore" macro the way
      i386 does.
      Signed-off-by: NGlauber Costa <gcosta@redhat.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      70f1bba4
    • I
      x86: fix savesegment() bug causing crashes on 64-bit · d9fc3fd3
      Ingo Molnar 提交于
      i spent a fair amount of time chasing a 64-bit bootup crash that manifested
      itself as bootup segfaults:
      
        S10network[1825]: segfault at 7f3e2b5d16b8 ip 00000031108748c9 sp 00007fffb9c14c70 error 4 in libc-2.7.so[3110800000+14d000]
      
      eventually causing init to die and panic the system:
      
        Kernel panic - not syncing: Attempted to kill init!
        Pid: 1, comm: init Not tainted 2.6.26-rc9-tip #13878
      
      after a maratonic bisection session, the bad commit turned out to be:
      
      | b7675791859075418199c7af86a116ea34eaf5bd is first bad commit
      | commit b7675791859075418199c7af86a116ea34eaf5bd
      | Author: Jeremy Fitzhardinge <jeremy@goop.org>
      | Date:   Wed Jun 25 00:19:00 2008 -0400
      |
      |     x86: remove open-coded save/load segment operations
      |
      |     This removes a pile of buggy open-coded implementations of savesegment
      |     and loadsegment.
      
      after some more bisection of this patch itself, it turns out that what
      makes the difference are the savesegment() changes to __switch_to().
      
      Taking a look at this portion of arch/x86/kernel/process_64.o revealed
      this crutial difference:
      
      | good:    99c:       8c e0                   mov    %fs,%eax
      |          99e:       89 45 cc                mov    %eax,-0x34(%rbp)
      |
      | bad:     99c:       8c 65 cc                mov    %fs,-0x34(%rbp)
      
      which is due to:
      
      |                 unsigned fsindex;
      | -               asm volatile("movl %%fs,%0" : "=r" (fsindex));
      | +               savesegment(fs, fsindex);
      
      savesegment() is implemented as:
      
       #define savesegment(seg, value)                                \
                asm("mov %%" #seg ",%0":"=rm" (value) : : "memory")
      
      note the "m" modifier - it allows GCC to generate the segment move
      into a memory operand as well.
      
      But regarding segment operands there's a subtle detail in the x86
      instruction set: the above 16-bit moves are zero-extend, but only
      if it goes to a register.
      
      If it goes to a memory operand, -0x34(%rbp) in the above case, there's
      no zero-extend to 32-bit and the instruction will only save 16 bits
      instead of the intended 32-bit.
      
      The other 16 bits is random data - which can cause problems when that
      value is used later on.
      
      The solution is to only allow segment operands to go to registers.
      This fix allows my test-system to boot up without crashing.
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      d9fc3fd3
  5. 11 7月, 2008 3 次提交
    • S
      sched_clock: stop maximum check on NO HZ · af52a90a
      Steven Rostedt 提交于
      Working with ftrace I would get large jumps of 11 millisecs or more with
      the clock tracer. This killed the latencing timings of ftrace and also
      caused the irqoff self tests to fail.
      
      What was happening is with NO_HZ the idle would stop the jiffy counter and
      before the jiffy counter was updated the sched_clock would have a bad
      delta jiffies to compare with the gtod with the maximum.
      
      The jiffies would stop and the last sched_tick would record the last gtod.
      On wakeup, the sched clock update would compare the gtod + delta jiffies
      (which would be zero) and compare it to the TSC. The TSC would have
      correctly (with a stable TSC) moved forward several jiffies. But because the
      jiffies has not been updated yet the clock would be prevented from moving
      forward because it would appear that the TSC jumped too far ahead.
      
      The clock would then virtually stop, until the jiffies are updated. Then
      the next sched clock update would see that the clock was very much behind
      since the delta jiffies is now correct. This would then jump the clock
      forward by several jiffies.
      
      This caused ftrace to report several milliseconds of interrupts off
      latency at every resume from NO_HZ idle.
      
      This patch adds hooks into the nohz code to disable the checking of the
      maximum clock update when nohz is in effect. It resumes the max check
      when nohz has updated the jiffies again.
      Signed-off-by: NSteven Rostedt <srostedt@redhat.com>
      Cc: Steven Rostedt <srostedt@redhat.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      af52a90a
    • S
      ftrace: add ftrace_kill_atomic · a2bb6a3d
      Steven Rostedt 提交于
      It has been suggested that I add a way to disable the function tracer
      on an oops. This code adds a ftrace_kill_atomic. It is not meant to be
      used in normal situations. It will disable the ftrace tracer, but will
      not perform the nice shutdown that requires scheduling.
      Signed-off-by: NSteven Rostedt <srostedt@redhat.com>
      Cc: Steven Rostedt <srostedt@redhat.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      a2bb6a3d
    • J
      x86_64: add pseudo-features for 32-bit compat syscall · 8d28aab5
      Jeremy Fitzhardinge 提交于
      Add pseudo-feature bits to describe whether the CPU supports sysenter
      and/or syscall from ia32-compat userspace.  This removes a hardcoded
      test in vdso32-setup.
      Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      8d28aab5