1. 08 12月, 2006 4 次提交
  2. 04 12月, 2006 1 次提交
    • L
      [ARM] 3881/4: xscale: clean up cp0/cp1 handling · afe4b25e
      Lennert Buytenhek 提交于
      XScale cores either have a DSP coprocessor (which contains a single
      40 bit accumulator register), or an iWMMXt coprocessor (which contains
      eight 64 bit registers.)
      
      Because of the small amount of state in the DSP coprocessor, access to
      the DSP coprocessor (CP0) is always enabled, and DSP context switching
      is done unconditionally on every task switch.  Access to the iWMMXt
      coprocessor (CP0/CP1) is enabled only when an iWMMXt instruction is
      first issued, and iWMMXt context switching is done lazily.
      
      CONFIG_IWMMXT is supposed to mean 'the cpu we will be running on will
      have iWMMXt support', but boards are supposed to select this config
      symbol by hand, and at least one pxa27x board doesn't get this right,
      so on that board, proc-xscale.S will incorrectly assume that we have a
      DSP coprocessor, enable CP0 on boot, and we will then only save the
      first iWMMXt register (wR0) on context switches, which is Bad.
      
      This patch redefines CONFIG_IWMMXT as 'the cpu we will be running on
      might have iWMMXt support, and we will enable iWMMXt context switching
      if it does.'  This means that with this patch, running a CONFIG_IWMMXT=n
      kernel on an iWMMXt-capable CPU will no longer potentially corrupt iWMMXt
      state over context switches, and running a CONFIG_IWMMXT=y kernel on a
      non-iWMMXt capable CPU will still do DSP context save/restore.
      
      These changes should make iWMMXt work on PXA3xx, and as a side effect,
      enable proper acc0 save/restore on non-iWMMXt capable xsc3 cores such
      as IOP13xx and IXP23xx (which will not have CONFIG_CPU_XSCALE defined),
      as well as setting and using HWCAP_IWMMXT properly.
      Signed-off-by: NLennert Buytenhek <buytenh@wantstofly.org>
      Acked-by: NDan Williams <dan.j.williams@intel.com>
      Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
      afe4b25e
  3. 02 12月, 2006 4 次提交
  4. 01 12月, 2006 1 次提交
  5. 30 11月, 2006 11 次提交
  6. 29 11月, 2006 4 次提交
  7. 27 11月, 2006 2 次提交
  8. 26 11月, 2006 1 次提交
    • P
      [PATCH] uml: make execvp safe for our usage · 5d48545e
      Paolo 'Blaisorblade' Giarrusso 提交于
      Reimplement execvp for our purposes - after we call fork() it is fundamentally
      unsafe to use the kernel allocator - current is not valid there.  So we simply
      pass to our modified execvp() a preallocated buffer.  This fixes a real bug
      and works very well in testing (I've seen indirectly warning messages from the
      forked thread - they went on the pipe connected to its stdout and where read
      as a number by UML, when calling read_output().  I verified the obtained
      number corresponded to "BUG:").
      
      The added use of __cant_sleep() is not a new bug since __cant_sleep() is
      already used in the same function - passing an atomicity parameter would be
      better but it would require huge change, stating that this function must not
      be called in atomic context and can sleep is a better idea (will make sure of
      this gradually).
      Signed-off-by: NPaolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
      Acked-by: NJeff Dike <jdike@addtoit.com>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      5d48545e
  9. 23 11月, 2006 2 次提交
  10. 22 11月, 2006 3 次提交
  11. 21 11月, 2006 4 次提交
  12. 20 11月, 2006 2 次提交
  13. 18 11月, 2006 1 次提交
    • L
      x86: be more careful when walking back the frame pointer chain · 808dbbb6
      Linus Torvalds 提交于
      When showing the stack backtrace, make sure that we never accept not
      only an unchanging frame pointer, but also a frame pointer that moves
      back down the stack frame.  It must always grow up (toward older stack
      frames).
      
      I doubt this has triggered, but a subtly corrupt stack with extremely
      unlucky contents could cause us to loop forever on a bogus endless frame
      pointer chain.
      
      This review was triggered by much worse problems happening in some of
      the other stack unwinding code.
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      808dbbb6