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path: root/include/asm-x86/nops.h
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2008-04-17x86: correct/clarify comment in nops.hMikael Pettersson
<asm-x86/nops.h> describes certain multibyte instructions as "generic" nops when in fact they aren't nops at all in 64-bit mode (missing REX.W causing truncation of a register). Update the comment to state that K8 or P6 style nops should be used in 64-bit mode. This matches what the alternatives code does. Signed-off-by: Mikael Pettersson <mikpe@it.uu.se> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-07x86: fix 64-bit asm NOPS for CONFIG_GENERIC_CPUSuresh Siddha
ASM_NOP's for 64-bit kernel with CONFIG_GENERIC_CPU is broken with the recent x86 nops merge. They were using GENERIC_NOPS which will truncate the upper 32bits of %rsi, because of the missing 64bit rex prefix. For now, fall back ASM NOPS for generic cpu to K8 NOPS, similar to the code before the wrong x86 nop merge. This should resolve the crash seen by Ingo on a test-system: BUG: unable to handle kernel paging request at 00000000d80d8ee8 IP: [<ffffffff802121af>] save_i387_ia32+0x61/0xd8 PGD b8e0067 PUD 51490067 PMD 0 Oops: 0000 [1] SMP CPU 2 Modules linked in: Pid: 3871, comm: distcc Not tainted 2.6.25-rc7-sched-devel.git-x86-latest.git #359 RIP: 0010:[<ffffffff802121af>] [<ffffffff802121af>] save_i387_ia32+0x61/0xd8 RSP: 0000:ffff81003abd3cb8 EFLAGS: 00010246 RAX: ffff810082e93400 RBX: 00000000ffc37f84 RCX: ffff8100d80d8ee0 RDX: 0000000000000000 RSI: 00000000d80d8ee0 RDI: ffff810082e93400 RBP: 00000000ffc37fdc R08: 00000000ffc37f88 R09: 0000000000000008 R10: ffff81003abd2000 R11: 0000000000000000 R12: ffff810082e93400 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff81011fb12dc0(0063) knlGS:00000000f7f1a6c0 CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: 00000000d80d8ee8 CR3: 0000000076922000 CR4: 00000000000006e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Process distcc (pid: 3871, threadinfo ffff81003abd2000, task ffff8100d80d8ee0) Stack: ffff8100bb670380 ffffffff8026de50 0000000000000118 0000000000000002 0000000000000002 ffff81003abd3e68 ffff81003abd3ed8 ffff81003abd3de8 ffff81003abd3d18 ffffffff80229785 ffff8100d80d8ee0 ffff810001041280 Call Trace: [<ffffffff8026de50>] ? __generic_file_aio_write_nolock+0x343/0x377 [<ffffffff80229785>] ? update_curr+0x54/0x64 [<ffffffff80227cd3>] ? ia32_setup_sigcontext+0x125/0x1d2 [<ffffffff8022839f>] ? ia32_setup_frame+0x73/0x1a5 [<ffffffff8020b2a5>] ? do_notify_resume+0x1aa/0x7db [<ffffffff8024ae8c>] ? getnstimeofday+0x31/0x85 [<ffffffff80249858>] ? ktime_get_ts+0x17/0x48 [<ffffffff80249933>] ? ktime_get+0xc/0x41 [<ffffffff8024973e>] ? hrtimer_nanosleep+0x75/0xd5 [<ffffffff80249261>] ? hrtimer_wakeup+0x0/0x21 [<ffffffff8020bfbc>] ? int_signal+0x12/0x17 [<ffffffff8030e6b3>] ? dummy_file_free_security+0x0/0x1 Code: a6 08 05 00 00 f6 40 14 01 74 34 4c 89 e7 48 0f ae 07 48 8b 86 08 05 00 00 80 78 02 00 79 02 db e2 90 8d b4 26 00 00 00 00 89 f6 <48> 8b 46 08 83 60 14 fe 0f 20 c0 48 83 c8 08 0f 22 c0 eb 07 c6 Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-02-26x86: add comments for NOPsH. Peter Anvin
Add comments describing the various NOP sequences. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-02-26x86: require family >= 6 if we are using P6 NOPsH. Peter Anvin
The P6 family of NOPs are only available on family >= 6 or above, so enforce that in the boot code. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30x86: move nop declarations into separate include fileAndi Kleen
Moving things out of processor.h is always a good thing. Also needed to avoid include loop in later patch. Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>