From: AKASHI Takahiro Date: Fri, 28 Nov 2014 05:26:34 +0000 (+0000) Subject: arm64: ptrace: add NT_ARM_SYSTEM_CALL regset X-Git-Tag: omap-for-v3.19/fixes-for-merge-window~18^2~13 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=766a85d7bc5d7f1ddd6de28bdb844eae45ec63b0;p=pandora-kernel.git arm64: ptrace: add NT_ARM_SYSTEM_CALL regset This regeset is intended to be used to get and set a system call number while tracing. There was some discussion about possible approaches to do so: (1) modify x8 register with ptrace(PTRACE_SETREGSET) indirectly, and update regs->syscallno later on in syscall_trace_enter(), or (2) define a dedicated regset for this purpose as on s390, or (3) support ptrace(PTRACE_SET_SYSCALL) as on arch/arm Thinking of the fact that user_pt_regs doesn't expose 'syscallno' to tracer as well as that secure_computing() expects a changed syscall number, especially case of -1, to be visible before this function returns in syscall_trace_enter(), (1) doesn't work well. We will take (2) since it looks much cleaner. Signed-off-by: AKASHI Takahiro Signed-off-by: Will Deacon --- Reading git-diff-tree failed