linux/arch/sh
Sohil Mehta 2fd0ebad27 arch: Reserve map_shadow_stack() syscall number for all architectures
commit c35559f94e ("x86/shstk: Introduce map_shadow_stack syscall")
recently added support for map_shadow_stack() but it is limited to x86
only for now. There is a possibility that other architectures (namely,
arm64 and RISC-V), that are implementing equivalent support for shadow
stacks, might need to add support for it.

Independent of that, reserving arch-specific syscall numbers in the
syscall tables of all architectures is good practice and would help
avoid future conflicts. map_shadow_stack() is marked as a conditional
syscall in sys_ni.c. Adding it to the syscall tables of other
architectures is harmless and would return ENOSYS when exercised.

Note, map_shadow_stack() was assigned #453 during the merge process
since #452 was taken by fchmodat2().

For Powerpc, map it to sys_ni_syscall() as is the norm for Powerpc
syscall tables.

For Alpha, map_shadow_stack() takes up #563 as Alpha still diverges from
the common syscall numbering system in the other architectures.

Link: https://lore.kernel.org/lkml/20230515212255.GA562920@debug.ba.rivosinc.com/
Link: https://lore.kernel.org/lkml/b402b80b-a7c6-4ef0-b977-c0f5f582b78a@sirena.org.uk/

Signed-off-by: Sohil Mehta <sohil.mehta@intel.com>
Reviewed-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2023-10-06 22:26:51 +02:00
..
boards sh updates for v6.6 2023-09-09 14:46:57 -07:00
boot sh: Use generic GCC library routines 2023-04-25 09:16:47 +02:00
cchips sh: hd64461: Handle virq offset for offchip IRQ base and HD64461 IRQ 2023-07-13 08:37:53 +02:00
configs treewide: drop CONFIG_EMBEDDED 2023-08-21 13:46:25 -07:00
drivers sh: push-switch: Reorder cleanup operations to avoid use-after-free bug 2023-09-09 21:54:20 +02:00
include Add x86 shadow stack support 2023-08-31 12:20:12 -07:00
kernel arch: Reserve map_shadow_stack() syscall number for all architectures 2023-10-06 22:26:51 +02:00
lib sh: Use generic GCC library routines 2023-04-25 09:16:47 +02:00
math-emu sh: math-emu: fix macro redefined warning 2023-03-23 10:00:03 +01:00
mm sh: implement the new page table range API 2023-08-24 16:20:23 -07:00
tools sh: Remove SH5-based Cayman platform 2020-08-14 22:05:06 -04:00
Kbuild sh: Move build rule for cchips/hd6446x/ to arch/sh/Kbuild 2023-07-05 18:55:18 +02:00
Kconfig - An extensive rework of kexec and crash Kconfig from Eric DeVolder 2023-08-29 14:53:51 -07:00
Kconfig.cpu docs: move superh documentation under Documentation/arch/ 2023-03-30 13:00:35 -06:00
Kconfig.debug sh: mcount.S: fix build error when PRINTK is not enabled 2023-03-23 10:02:02 +01:00
Makefile sh: Remove compiler flag duplication 2023-07-05 18:55:25 +02:00