Commit 621881df authored Apr 08, 2019 by Jean-Philippe Brucker Committed by Greg Kroah-Hartman May 21, 2019

arm64: Clear OSDLR_EL1 on CPU boot



commit 6fda41bf12615ee7c3ddac88155099b1a8cf8d00 upstream.

Some firmwares may reboot CPUs with OS Double Lock set. Make sure that
it is unlocked, in order to use debug exceptions.

Cc: <stable@vger.kernel.org>
Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 20230611

arch/arm64/kernel/debug-monitors.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -132,6 +132,7 @@ NOKPROBE_SYMBOL(disable_debug_monitors);
		*/
		static int clear_os_lock(unsigned int cpu)
		{
		write_sysreg(0, osdlr_el1);
		write_sysreg(0, oslar_el1);
		isb();
		return 0;