On 06/09/2015 09:01 PM, Andy Lutomirski wrote: > On Tue, Jun 9, 2015 at 11:54 AM, Denys Vlasenko <[email protected]> wrote: >> This doesn't change much, but this uses shorter 32-bit insns: >> >> -48 8b 74 24 68 mov 0x68(%rsp),%rsi >> -48 8b 7c 24 70 mov 0x70(%rsp),%rdi >> -48 8b 54 24 60 mov 0x60(%rsp),%rdx >> +8b 74 24 68 mov 0x68(%rsp),%esi >> +8b 7c 24 70 mov 0x70(%rsp),%edi >> +8b 54 24 60 mov 0x60(%rsp),%edx >> >> Since these are the only uses of RESTORE_RSI_RDI[_RDX], drop these macros. >> > > It probably doesn't matter for these fast paths, but, for the full > slow path return, we really do need to restore the full pt_regs. > After all, the syscall we're returning from might be sigreturn.
This is compat 32-bit syscall handling code. IIUC we do not restore high half of any registers for 32-bit tasks. Am I missing something? -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
