• Mathieu Desnoyers's avatar
    x86: Add support for restartable sequences · d6761b8f
    Mathieu Desnoyers authored
    Call the rseq_handle_notify_resume() function on return to userspace if
    TIF_NOTIFY_RESUME thread flag is set.
    
    Perform fixup on the pre-signal frame when a signal is delivered on top
    of a restartable sequence critical section.
    
    Check that system calls are not invoked from within rseq critical
    sections by invoking rseq_signal() from syscall_return_slowpath().
    With CONFIG_DEBUG_RSEQ, such behavior results in termination of the
    process with SIGSEGV.
    Signed-off-by: default avatarMathieu Desnoyers <mathieu.desnoyers@efficios.com>
    Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
    Reviewed-by: default avatarThomas Gleixner <tglx@linutronix.de>
    Cc: Joel Fernandes <joelaf@google.com>
    Cc: Peter Zijlstra <peterz@infradead.org>
    Cc: Catalin Marinas <catalin.marinas@arm.com>
    Cc: Dave Watson <davejwatson@fb.com>
    Cc: Will Deacon <will.deacon@arm.com>
    Cc: Andi Kleen <andi@firstfloor.org>
    Cc: "H . Peter Anvin" <hpa@zytor.com>
    Cc: Chris Lameter <cl@linux.com>
    Cc: Russell King <linux@arm.linux.org.uk>
    Cc: Andrew Hunter <ahh@google.com>
    Cc: Michael Kerrisk <mtk.manpages@gmail.com>
    Cc: "Paul E . McKenney" <paulmck@linux.vnet.ibm.com>
    Cc: Paul Turner <pjt@google.com>
    Cc: Boqun Feng <boqun.feng@gmail.com>
    Cc: Josh Triplett <josh@joshtriplett.org>
    Cc: Steven Rostedt <rostedt@goodmis.org>
    Cc: Ben Maurer <bmaurer@fb.com>
    Cc: linux-api@vger.kernel.org
    Cc: Andy Lutomirski <luto@amacapital.net>
    Cc: Andrew Morton <akpm@linux-foundation.org>
    Cc: Linus Torvalds <torvalds@linux-foundation.org>
    Link: https://lkml.kernel.org/r/20180602124408.8430-7-mathieu.desnoyers@efficios.com
    d6761b8f
signal.c 22.8 KB