Revision 61f01dd941ba9e06d2bf05994450ecc3d61b6b8b authored by Andy Lutomirski on 26 April 2015, 23:47:59 UTC, committed by Linus Torvalds on 27 April 2015, 00:57:38 UTC
AMD CPUs don't reinitialize the SS descriptor on SYSRET, so SYSRET with SS == 0 results in an invalid usermode state in which SS is apparently equal to __USER_DS but causes #SS if used. Work around the issue by setting SS to __KERNEL_DS __switch_to, thus ensuring that SYSRET never happens with SS set to NULL. This was exposed by a recent vDSO cleanup. Fixes: e7d6eefaaa44 x86/vdso32/syscall.S: Do not load __USER32_DS to %ss Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Peter Anvin <hpa@zytor.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Denys Vlasenko <vda.linux@googlemail.com> Cc: Brian Gerst <brgerst@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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| File | Mode | Size |
|---|---|---|
| .gitignore | -rw-r--r-- | 13 bytes |
| 00-INDEX | -rw-r--r-- | 590 bytes |
| Makefile | -rw-r--r-- | 137 bytes |
| NO_HZ.txt | -rw-r--r-- | 16.5 KB |
| highres.txt | -rw-r--r-- | 12.3 KB |
| hpet.txt | -rw-r--r-- | 1.5 KB |
| hpet_example.c | -rw-r--r-- | 5.4 KB |
| hrtimers.txt | -rw-r--r-- | 8.7 KB |
| timekeeping.txt | -rw-r--r-- | 8.8 KB |
| timer_stats.txt | -rw-r--r-- | 3.0 KB |
| timers-howto.txt | -rw-r--r-- | 3.8 KB |
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