linux/arch/x86/entry
Thomas Gleixner e441a2ae0e x86/entry/32: Remove the 0/-1 distinction from exception entries
Nothing cares about the -1 "mark as interrupt" in the errorcode of
exception entries. It's only used to fill the error code when a signal is
delivered, but this is already inconsistent vs. 64 bit as there all
exceptions which do not have an error code set it to 0. So if 32 bit
applications would care about this, then they would have noticed more than
a decade ago.

Just use 0 for all excpetions which do not have an errorcode consistently.

This does neither break /proc/$PID/syscall because this interface examines
the error code / syscall number which is on the stack and that is set to -1
(no syscall) in common_exception unconditionally for all exceptions. The
push in the entry stub is just there to fill the hardware error code slot
on the stack for consistency of the stack layout.

A transient observation of 0 is possible, but that's true for the other
exceptions which use 0 already as well and that interface is an unreliable
snapshot of dubious correctness anyway.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Link: https://lkml.kernel.org/r/87mu94m7ky.fsf@nanos.tec.linutronix.de
2020-02-29 12:45:54 +01:00
..
syscalls threads-v5.6 2020-01-29 19:38:34 -08:00
vdso kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
vsyscall y2038: syscall implementation cleanups 2019-12-01 14:00:59 -08:00
calling.h context_tracking: Rename context_tracking_is_enabled() => context_tracking_enabled() 2019-10-29 10:01:12 +01:00
common.c x86/ioperm: Move TSS bitmap update to exit to user work 2019-11-16 11:24:03 +01:00
entry_32.S x86/entry/32: Remove the 0/-1 distinction from exception entries 2020-02-29 12:45:54 +01:00
entry_64_compat.S x86/asm: Change all ENTRY+ENDPROC to SYM_FUNC_* 2019-10-18 11:58:33 +02:00
entry_64.S x86/entry/64: Add instruction suffix to SYSRET 2020-01-09 12:33:43 +01:00
Makefile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
syscall_32.c syscalls/x86: Use the correct function type for sys_ni_syscall 2019-10-11 12:49:18 +02:00
syscall_64.c syscalls/x86: Use the correct function type for sys_ni_syscall 2019-10-11 12:49:18 +02:00
thunk_32.S x86/asm/entry: Annotate THUNKs 2019-10-18 09:58:59 +02:00
thunk_64.S x86/asm/entry: Annotate THUNKs 2019-10-18 09:58:59 +02:00