Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 855b6232 authored by Nicholas Piggin's avatar Nicholas Piggin Committed by Michael Ellerman
Browse files

powerpc/64: hard disable irqs on the panic()ing CPU 



Similar to previous patches, hard disable interrupts when a CPU is
in panic. This reduces the chance the watchdog has to interfere with
the panic, and avoids any other type of masked interrupt being
executed when crashing which minimises the length of the crash path.

Signed-off-by: default avatarNicholas Piggin <npiggin@gmail.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
parent de6e5d38

arch/powerpc/kernel/setup-common.c

+10 −2
Original line number Diff line number Diff line
@@ -700,11 +700,18 @@ EXPORT_SYMBOL(check_legacy_ioport); 
static int ppc_panic_event(struct notifier_block *this,

                             unsigned long event, void *ptr)

{

	/*

	 * panic does a local_irq_disable, but we really

	 * want interrupts to be hard disabled.

	 */

	hard_irq_disable();



	/*

	 * If firmware-assisted dump has been registered then trigger

	 * firmware-assisted dump and let firmware handle everything else.

	 */

	crash_fadump(NULL, ptr);

	if (ppc_md.panic)

		ppc_md.panic(ptr);  /* May not return */

	return NOTIFY_DONE;

}
@@ -716,7 +723,8 @@ static struct notifier_block ppc_panic_block = { 


void __init setup_panic(void)

{

	if (!ppc_md.panic)

	/* PPC64 always does a hard irq disable in its panic handler */

	if (!IS_ENABLED(CONFIG_PPC64) && !ppc_md.panic)

		return;

	atomic_notifier_chain_register(&panic_notifier_list, &ppc_panic_block);

}