forked from Minki/linux
280270828f
I've finally tracked down why my CR signal-unwind test case still fails on little-endian. The problem turned to be that the kernel installs a signal trampoline in the vDSO, and provides a DWARF CFI record for that trampoline. This CFI describes the save location for CR: rsave (70, 38*RSIZE + (RSIZE - CRSIZE)) which is correct for big-endian, but points to the wrong word on little-endian. This is wrong no matter which ABI. In addition, for the ELFv2 ABI, we should not only provide a CFI record for register 70 (cr2), but for all CR fields separately. Strictly speaking, I guess this would mean providing two separate vDSO images, one for ELFv1 processes and one for ELFv2 processes (or maybe playing some tricks with conditional DWARF expressions). However, having CFI records for the other CR fields in ELFv1 is not actually wrong, they just will be ignored. So it seems the simplest fix would be just to always provide CFI for all the fields. Signed-off-by: Ulrich Weigand <Ulrich.Weigand@de.ibm.com> Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> |
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| .gitignore | ||
| cacheflush.S | ||
| datapage.S | ||
| getcpu.S | ||
| gettimeofday.S | ||
| Makefile | ||
| note.S | ||
| sigtramp.S | ||
| vdso64_wrapper.S | ||
| vdso64.lds.S | ||