Re: arm64: Register modification during syscall entry/exit stop
From: Dave Martin <Dave.Martin@arm.com>
Date: 2020-06-01 09:23:34
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On Sun, May 31, 2020 at 12:20:51PM -0400, Keno Fischer wrote:
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Can't PTRACE_SYSEMU be emulated by using PTRACE_SYSCALL, cancelling the syscall at the syscall enter stop, then modifying the regs at the syscall exit stop?Yes, it can. The idea behind SYSEMU is to be able to save half the ptrace traps that would require, in theory making the ptracer a decent amount faster. That said, the x7 issue is orthogonal to SYSEMU, you'd have the same issues if you used PTRACE_SYSCALL.
Right, I just wondered whether there was some deeper difference between the two approaches. Cheers ---Dave _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel