Re: [PATCH 2/2] arch: Reserve map_shadow_stack() syscall number for all architectures
Michael Ellerman <[email protected]>
| Newsgroups | gmane.linux.ports.alpha,gmane.linux.kernel,gmane.linux.kernel.cross-arch,gmane.linux.kernel.api,gmane.linux.kernel.perf.user,gmane.linux.ports.sparc,gmane.linux.ports.ia64,gmane.linux.ports.parisc,gmane.linux.ports.sh.devel,gmane.linux.ports.ppc64.devel,gmane.linux.ports.mips,gmane.linux.ports.arm.kernel |
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| Message-ID | <[email protected]> |
"Edgecombe, Rick P" <[email protected]> writes: > On Mon, 2023-09-11 at 18:02 +0000, Sohil Mehta wrote: >> diff --git a/arch/powerpc/kernel/syscalls/syscall.tbl >> b/arch/powerpc/kernel/syscalls/syscall.tbl >> index 20e50586e8a2..2767b8a42636 100644 >> --- a/arch/powerpc/kernel/syscalls/syscall.tbl >> +++ b/arch/powerpc/kernel/syscalls/syscall.tbl >> @@ -539,3 +539,4 @@ >> 450 nospu set_mempolicy_home_node sys_set_mempolicy_hom >> e_node >> 451 common cachestat sys_cachestat >> 452 common fchmodat2 sys_fchmodat2 >> +453 common map_shadow_stack sys_map_shadow_stack > > I noticed in powerpc, the not implemented syscalls are manually mapped > to sys_ni_syscall. It also has some special extra sys_ni_syscall() > implementation bits to handle both ARCH_HAS_SYSCALL_WRAPPER and > !ARCH_HAS_SYSCALL_WRAPPER. So wondering if it might need special > treatment. Did you see those parts? I don't think it needs any special treatment. It's processed by the same script as other arches (scripts/syscalltbl.sh). So if there's no compat or native entry it will default to sys_ni_syscall. I think it's just habit/historical that we always spell out sys_ni_syscall. cheers