kernel/git/stable/linux.git/include/asm-x86/system.h, branch master

x86, um: ... and asm-x86 move

2008-10-23T05:55:20+00:00

Signed-off-by: Al Viro Signed-off-by: H. Peter Anvin

x86: add memory clobber in switch_to()

2008-10-13T08:21:12+00:00

Segment registers are reloaded, so we should add a memory clobber. The generated assembly code is identical in my tests, but this doesn't mean it is necessarily true for all configurations/compilers. x86_64 already has the memory clobber. Signed-off-by: Vegard Nossum Signed-off-by: Ingo Molnar

x86: consolidate header guards

2008-07-22T19:31:34+00:00

This patch is the result of an automatic script that consolidates the format of all the headers in include/asm-x86/. The format: 1. No leading underscore. Names with leading underscores are reserved. 2. Pathname components are separated by two underscores. So we can distinguish between mm_types.h and mm/types.h. 3. Everything except letters and numbers are turned into single underscores. Signed-off-by: Vegard Nossum

x86: fix savesegment() bug causing crashes on 64-bit

2008-07-11T17:51:47+00:00

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 | 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: Ingo Molnar

x86/paravirt, 64-bit: make load_gs_index() a paravirt operation

2008-07-08T11:15:58+00:00

Signed-off-by: Eduardo Habkost Signed-off-by: Jeremy Fitzhardinge Cc: xen-devel Cc: Stephen Tweedie Cc: Eduardo Habkost Cc: Mark McLoughlin Signed-off-by: Ingo Molnar

x86: add memory clobber to save/loadsegment

2008-07-08T11:10:23+00:00

Add "memory" clobbers to savesegment and loadsegment, since they can affect memory accesses and we never want the compiler to reorder them with respect to memory references. Signed-off-by: Jeremy Fitzhardinge Cc: xen-devel Cc: Stephen Tweedie Cc: Eduardo Habkost Cc: Mark McLoughlin Signed-off-by: Ingo Molnar

Merge branch 'x86/mpparse' into x86/devel

2008-07-08T09:14:58+00:00

Conflicts: arch/x86/Kconfig arch/x86/kernel/io_apic_32.c arch/x86/kernel/setup_64.c arch/x86/mm/init_32.c Signed-off-by: Ingo Molnar

x86: use symbolic constant in stts()

2008-05-27T08:04:29+00:00

Signed-off-by: Jeremy Fitzhardinge Signed-off-by: Thomas Gleixner

x86: move es7000_plat out of mpparse.c

2008-05-25T08:55:12+00:00

Signed-off-by: Alexey Starikovskiy Signed-off-by: Ingo Molnar

include/asm-x86/system.h: checkpatch cleanups - formatting only

2008-04-17T15:41:28+00:00

Signed-off-by: Joe Perches Signed-off-by: Ingo Molnar