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  1. 31 10月, 2005 6 次提交
  3. 28 10月, 2005 1 次提交
  5. 11 10月, 2005 1 次提交
  7. 10 10月, 2005 1 次提交
    • R
      [PATCH] x86_64: Set up safe page tables during resume · 3dd08325
      由 Rafael J. Wysocki 提交于 
      The following patch makes swsusp avoid the possible temporary corruption
of page translation tables during resume on x86-64.  This is achieved by
creating a copy of the relevant page tables that will not be modified by
swsusp and can be safely used by it on resume.

The problem is that during resume on x86-64 swsusp may temporarily
corrupt the page tables used for the direct mapping of RAM.  If that
happens, a page fault occurs and cannot be handled properly, which leads
to the solid hang of the affected system.  This leads to the loss of the
system's state from before suspend and may result in the loss of data or
the corruption of filesystems, so it is a serious issue.  Also, it
appears to happen quite often (for me, as often as 50% of the time).

The problem is related to the fact that (at least) one of the PMD
entries used in the direct memory mapping (starting at PAGE_OFFSET)
points to a page table the physical address of which is much greater
than the physical address of the PMD entry itself.  Moreover,
unfortunately, the physical address of the page table before suspend
(i.e.  the one stored in the suspend image) happens to be different to
the physical address of the corresponding page table used during resume
(i.e.  the one that is valid right before swsusp_arch_resume() in
arch/x86_64/kernel/suspend_asm.S is executed).  Thus while the image is
restored, the "offending" PMD entry gets overwritten, so it does not
point to the right physical address any more (i.e.  there's no page
table at the address pointed to by it, because it points to the address
the page table has been at during suspend).  Consequently, if the PMD
entry is used later on, and it _is_ used in the process of copying the
image pages, a page fault occurs, but it cannot be handled in the normal
way and the system hangs.

In principle we can call create_resume_mapping() from
swsusp_arch_resume() (ie.  from suspend_asm.S), but then the memory
allocations in create_resume_mapping(), resume_pud_mapping(), and
resume_pmd_mapping() must be made carefully so that we use _only_
NosaveFree pages in them (the other pages are overwritten by the loop in
swsusp_arch_resume()).  Additionally, we are in atomic context at that
time, so we cannot use GFP_KERNEL.  Moreover, if one of the allocations
fails, we should free all of the allocated pages, so we need to trace
them somehow.

All of this is done in the appended patch, except that the functions
populating the page tables are located in arch/x86_64/kernel/suspend.c
rather than in init.c.  It may be done in a more elegan way in the
future, with the help of some swsusp patches that are in the works now.

[AK: move some externs into headers, renamed a function]
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      3dd08325
  9. 05 10月, 2005 1 次提交
    • A
      [PATCH] x86_64: Drop global bit from early low mappings · 944d2647
      由 Andi Kleen 提交于 
      Drop global bit from early low mappings

Suggested by Linus, originally also proposed by Suresh.

This fixes a race condition with early start of udev, originally
tracked down by Suresh B. Siddha. The problem was that switching
to the user space VM would not clear the global low mappings
for the beginning of memory, which lead to memory corruption.

Drop the global bits.

The kernel mapping stays global because it should stay constant.
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      944d2647
  11. 04 10月, 2005 1 次提交
  13. 01 10月, 2005 1 次提交
  15. 30 9月, 2005 2 次提交
  17. 28 9月, 2005 1 次提交
  19. 18 9月, 2005 2 次提交
  21. 15 9月, 2005 2 次提交
    • D
      [LIB]: Consolidate _atomic_dec_and_lock() · 4db2ce01
      由 David S. Miller 提交于 
      Several implementations were essentialy a common piece of C code using
the cmpxchg() macro.  Put the implementation in one spot that everyone
can share, and convert sparc64 over to using this.

Alpha is the lone arch-specific implementation, which codes up a
special fast path for the common case in order to avoid GP reloading
which a pure C version would require.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      4db2ce01
    • L
      Partially revert "Fix time going twice as fast problem on ATI Xpress chipsets" · 1619cca2
      由 Linus Torvalds 提交于 
      Commit 66759a01 introduced the fix for
time ticking too fast on some boards by disabling one of the doubly
connected timer pins on ATI boards.

However, it ends up being _much_ too broad a brush, and that just makes
some other ATI boards not work at all since they now have no timer
source.

So disable the automatic ATI southbridge detection, and just rely on
people who see this problem disabling it by hand with the option
"disable_timer_pin_1" on the kernel command line.

Maybe somebody can figure out the proper tests at a later date.
Acked-by: NPeter Osterlund <petero2@telia.com>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      1619cca2
  23. 14 9月, 2005 1 次提交
  25. 13 9月, 2005 20 次提交