Sergei Trofimovich 7d9da660af ia64: fix user_stack_pointer() for ptrace() ... commit 7ad1e366167837daeb93d0bacb57dee820b0b898 upstream. ia64 has two stacks: - memory stack (or stack), pointed at by by r12 - register backing store (register stack), pointed at by ar.bsp/ar.bspstore with complications around dirty register frame on CPU. In [1] Dmitry noticed that PTRACE_GET_SYSCALL_INFO returns the register stack instead memory stack. The bug comes from the fact that user_stack_pointer() and current_user_stack_pointer() don't return the same register: ulong user_stack_pointer(struct pt_regs *regs) { return regs->ar_bspstore; } #define current_user_stack_pointer() (current_pt_regs()->r12) The change gets both back in sync. I think ptrace(PTRACE_GET_SYSCALL_INFO) is the only affected user by this bug on ia64. The change fixes 'rt_sigreturn.gen.test' strace test where it was observed initially. Link: https://bugs.gentoo.org/769614 [1] Link: https://lkml.kernel.org/r/20210331084447.2561532-1-slyfox@gentoo.org Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org> Reported-by: Dmitry V. Levin <ldv@altlinux.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2021-04-14 08:41:58 +02:00
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asm	ia64: fix user_stack_pointer() for ptrace()	2021-04-14 08:41:58 +02:00
uapi/asm	Cleanup some leftover para-virtualization pieces	2019-12-04 11:05:13 -08:00