This is a note to let you know that I've just added the patch titled powerpc/sysdev: fix incorrect use to determine if list is empty to the 5.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: powerpc-sysdev-fix-incorrect-use-to-determine-if-lis.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit ea2e2b75c0b2981f97ad16fa3b8f545a0772de11 Author: Jakob Koschel <jakobkoschel@xxxxxxxxx> Date: Mon Feb 28 15:24:33 2022 +0100 powerpc/sysdev: fix incorrect use to determine if list is empty [ Upstream commit fa1321b11bd01752f5be2415e74a0e1a7c378262 ] 'gtm' will *always* be set by list_for_each_entry(). It is incorrect to assume that the iterator value will be NULL if the list is empty. Instead of checking the pointer it should be checked if the list is empty. Fixes: 83ff9dcf375c ("powerpc/sysdev: implement FSL GTM support") Signed-off-by: Jakob Koschel <jakobkoschel@xxxxxxxxx> Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20220228142434.576226-1-jakobkoschel@xxxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/arch/powerpc/sysdev/fsl_gtm.c b/arch/powerpc/sysdev/fsl_gtm.c index 8963eaffb1b7..39186ad6b3c3 100644 --- a/arch/powerpc/sysdev/fsl_gtm.c +++ b/arch/powerpc/sysdev/fsl_gtm.c @@ -86,7 +86,7 @@ static LIST_HEAD(gtms); */ struct gtm_timer *gtm_get_timer16(void) { - struct gtm *gtm = NULL; + struct gtm *gtm; int i; list_for_each_entry(gtm, >ms, list_node) { @@ -103,7 +103,7 @@ struct gtm_timer *gtm_get_timer16(void) spin_unlock_irq(>m->lock); } - if (gtm) + if (!list_empty(>ms)) return ERR_PTR(-EBUSY); return ERR_PTR(-ENODEV); }