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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2021-05-23 06:07:33 -1000 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2021-05-23 06:07:33 -1000 |
| commit | 28ceac6959e1db015729c52ec74e0a4ff496c2b8 (patch) | |
| tree | 1fda20fa530a3bd3f2c96113d644d68921145738 /Documentation | |
| parent | 4d7620341eda38573a73ab63c33423534fa38eb9 (diff) | |
| parent | d72500f992849d31ebae8f821a023660ddd0dcc2 (diff) | |
Merge tag 'powerpc-5.13-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc fixes from Michael Ellerman:
- Fix breakage of strace (and other ptracers etc.) when using the new
scv ABI (Power9 or later with glibc >= 2.33).
- Fix early_ioremap() on 64-bit, which broke booting on some machines.
Thanks to Dmitry V. Levin, Nicholas Piggin, Alexey Kardashevskiy, and
Christophe Leroy.
* tag 'powerpc-5.13-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/64s/syscall: Fix ptrace syscall info with scv syscalls
powerpc/64s/syscall: Use pt_regs.trap to distinguish syscall ABI difference between sc and scv syscalls
powerpc: Fix early setup to make early_ioremap() work
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/powerpc/syscall64-abi.rst | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/Documentation/powerpc/syscall64-abi.rst b/Documentation/powerpc/syscall64-abi.rst index dabee3729e5a..56490c4c0c07 100644 --- a/Documentation/powerpc/syscall64-abi.rst +++ b/Documentation/powerpc/syscall64-abi.rst @@ -109,6 +109,16 @@ auxiliary vector. scv 0 syscalls will always behave as PPC_FEATURE2_HTM_NOSC. +ptrace +------ +When ptracing system calls (PTRACE_SYSCALL), the pt_regs.trap value contains +the system call type that can be used to distinguish between sc and scv 0 +system calls, and the different register conventions can be accounted for. + +If the value of (pt_regs.trap & 0xfff0) is 0xc00 then the system call was +performed with the sc instruction, if it is 0x3000 then the system call was +performed with the scv 0 instruction. + vsyscall ======== |