On Tue, Sep 28, 2010 at 11:50 AM, Al Viro <viro@xxxxxxxxxxxxxxxx> wrote: > > Put the original syscall number into ->regs[0] when we leave syscall > with error. Use it in restart logics. Everything else will have > it 0 since we pass through SAVE_SOME on all the ways in. Note that > in places like bad_stack and inllegal_syscall we leave it 0 - it's > not restartable. > > Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx> Building 2.6.36-rc8 on a 32-bit mipsel system gives me the following compile failure: LD .tmp_vmlinux1 arch/mips/built-in.o:/home/shane/linux-mips.org/linux/arch/mips/kernel/scall32-o32.S:66: undefined reference to `PR_R2' arch/mips/built-in.o:/home/shane/linux-mips.org/linux/arch/mips/kernel/scall32-o32.S:66: undefined reference to `PR_R2' make: *** [.tmp_vmlinux1] Error 1 I tracked it down to this patch. In particular, I believe the change to scall32-o32.S is causing the problem. > diff --git a/arch/mips/kernel/scall32-o32.S b/arch/mips/kernel/scall32-o32.S > index 17202bb..d3edb9f 100644 > --- a/arch/mips/kernel/scall32-o32.S > +++ b/arch/mips/kernel/scall32-o32.S > @@ -63,9 +63,9 @@ stack_done: > sw t0, PT_R7(sp) # set error flag > beqz t0, 1f > > + lw t1, PR_R2(sp) # syscall number Should this be PT_R2(sp), rather than PR_R2(sp)? > negu v0 # error > - sw v0, PT_R0(sp) # set flag for syscall > - # restarting > + sw t1, PT_R0(sp) # save it for syscall restarting > 1: sw v0, PT_R2(sp) # result > > o32_syscall_exit: > @@ -104,9 +104,9 @@ syscall_trace_entry: > sw t0, PT_R7(sp) # set error flag > beqz t0, 1f > > + lw t1, PT_R2(sp) # syscall number > negu v0 # error > - sw v0, PT_R0(sp) # set flag for syscall > - # restarting > + sw t1, PT_R0(sp) # save it for syscall restarting > 1: sw v0, PT_R2(sp) # result > > j syscall_exit > @@ -170,7 +170,6 @@ stackargs: > */ > bad_stack: > negu v0 # error > - sw v0, PT_R0(sp) > sw v0, PT_R2(sp) > li t0, 1 # set error flag > sw t0, PT_R7(sp) Changing PR_R2(sp) to PT_R2(sp) allows me to compile and successfully boot 2.6.36-rc8. I'll whip up a quick patch to make this change and submit it. Shane -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
