mirror of https://gitee.com/openkylin/linux.git
6bc31bdc55
On SVM we set the instruction length of skipped instructions to hard-coded, well known values, which could be wrong when (bogus, but valid) prefixes (REX, segment override) are used. Newer AMD processors (Fam10h 45nm and better, aka. PhenomII or AthlonII) have an explicit NEXTRIP field in the VMCB containing the desired information. Since it is cheap to do so, we use this field to override the guessed value on newer processors. A fix for older CPUs would be rather expensive, as it would require to fetch and partially decode the instruction. As the problem is not a security issue and needs special, handcrafted code to trigger (no compiler will ever generate such code), I omit a fix for older CPUs. If someone is interested, I have both a patch for these CPUs as well as demo code triggering this issue: It segfaults under KVM, but runs perfectly on native Linux. Signed-off-by: Andre Przywara <andre.przywara@amd.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> |
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| .. | ||
| boot | ||
| configs | ||
| crypto | ||
| ia32 | ||
| include/asm | ||
| kernel | ||
| kvm | ||
| lguest | ||
| lib | ||
| math-emu | ||
| mm | ||
| oprofile | ||
| pci | ||
| power | ||
| tools | ||
| vdso | ||
| video | ||
| xen | ||
| Kbuild | ||
| Kconfig | ||
| Kconfig.cpu | ||
| Kconfig.debug | ||
| Makefile | ||
| Makefile_32.cpu | ||