Re: [PATCH] Fix ptrace compat wrapper for fpu register access
From: Michael Neuling <hidden>
Date: 2009-03-30 09:52:31
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So if you're looking fixing 32 bit apps ptracing 64 bit apps, does that mean we can get a single 32 bit GDB that'll ptrace both 64 and 32 bit apps?Currently gdb only supports 32x64 debugging for the SPU.
Ok, thanks.
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@@ -263,7 +263,8 @@ long compat_arch_ptrace(struct task_struct *child, com
pat
quoted hunk ↗ jump to hunk
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_long_t request,quoted
ret = ptrace_put_reg(child, numReg, freg); } else { flush_fp_to_thread(child); - ((unsigned int *)child->thread.regs)[index] = data; + ((unsigned int *)child->thread.regs) + [FPRINDEX(index)] = data;This index is into the ptregs structure not the fpr. I'm not sure the FPRINDEX macro is applicable here.You're right, this hunk is bogus. But indexing off thread.regs is totally bogus as well. I think what was intented is this:@@ -263,7 +263,9 @@ long compat_arch_ptrace(struct task_stru ret = ptrace_put_reg(child, numReg, freg); } else { flush_fp_to_thread(child); - ((unsigned int *)child->thread.regs)[index] = data; + ((unsigned int *)child->thread.fpr) + [TS_FPRWIDTH * (numReg - PT_FPR0) * 2 + + index % 2] = data;
I think the indexing here should be the same as PEEKUSR_3264. This looks better but all this magic indexing makes me want to vomit. I'd like to fix this stuff but I've been avoiding it since we don't have a decent test case/suite to make sure it's not bust. Mikey
ret = 0; } break; But gdb does not actually use PPC_PTRACE_POKEUSR_3264. Andreas. -- Andreas Schwab, schwab@linux-m68k.org GPG Key fingerprint = 58CA 54C7 6D53 942B 1756 01D3 44D5 214B 8276 4ED5 "And now for something completely different."