[POWERPC] Fix 64 bits vDSO DWARF info for CR register
authorBenjamin Herrenschmidt <benh@au1.ibm.com>
Wed, 17 Oct 2007 04:26:50 +0000 (14:26 +1000)
committerPaul Mackerras <paulus@samba.org>
Wed, 17 Oct 2007 12:30:09 +0000 (22:30 +1000)
commit081c11a5d0cc24ab58adc7de2ddf209149bf176f
treee1b3c185b0d148a6ee5a87ac47edb5e6ae2756fd
parentf66bce5e6aa1388289c04496c3fcae7bebf5f905
[POWERPC] Fix 64 bits vDSO DWARF info for CR register

The current DWARF info for CR are incorrect, causing the gcc unwinder to
go to lunch if we take a segfault in the vdso.  This fixes it.

Problem identified by Andrew Haley, and fix provided by Jakub Jelinek
(thanks !).

Unfortunately, a bug in gcc cause it to not quite work either, but that
is being fixed separately with something around the lines of:

linux-unwind.h:

     fs->regs.reg[R_CR2].loc.offset = (long) &regs->ccr - new_cfa;
+    /* CR? regs are just 32-bit and PPC is big-endian.  */
+    fs->regs.reg[R_CR2].loc.offset += sizeof (long) - 4;

(According to Jakub)

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
arch/powerpc/kernel/vdso64/sigtramp.S