From 348ea30f51fc63ce3c7fd7dba6043e8e3ee0ef34 Mon Sep 17 00:00:00 2001 From: Nathan Lynch Date: Tue, 28 May 2019 18:28:01 -0500 Subject: powerpc/pseries: avoid blocking in irq when queuing hotplug events A couple of bugs in queue_hotplug_event(): 1. Unchecked kmalloc result which could lead to an oops. 2. Use of GFP_KERNEL allocations in interrupt context (this code's only caller is ras_hotplug_interrupt()). Use kmemdup to avoid open-coding the allocation+copy and check for failure; use GFP_ATOMIC for both allocations. Ultimately it probably would be better to avoid or reduce allocations in this path if possible. Signed-off-by: Nathan Lynch Signed-off-by: Michael Ellerman --- arch/powerpc/platforms/pseries/dlpar.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/arch/powerpc/platforms/pseries/dlpar.c b/arch/powerpc/platforms/pseries/dlpar.c index c852024044bb..4989c5762398 100644 --- a/arch/powerpc/platforms/pseries/dlpar.c +++ b/arch/powerpc/platforms/pseries/dlpar.c @@ -390,11 +390,11 @@ void queue_hotplug_event(struct pseries_hp_errorlog *hp_errlog) struct pseries_hp_work *work; struct pseries_hp_errorlog *hp_errlog_copy; - hp_errlog_copy = kmalloc(sizeof(struct pseries_hp_errorlog), - GFP_KERNEL); - memcpy(hp_errlog_copy, hp_errlog, sizeof(struct pseries_hp_errorlog)); + hp_errlog_copy = kmemdup(hp_errlog, sizeof(*hp_errlog), GFP_ATOMIC); + if (!hp_errlog_copy) + return; - work = kmalloc(sizeof(struct pseries_hp_work), GFP_KERNEL); + work = kmalloc(sizeof(struct pseries_hp_work), GFP_ATOMIC); if (work) { INIT_WORK((struct work_struct *)work, pseries_hp_work_fn); work->errlog = hp_errlog_copy; -- cgit v1.2.3-59-g8ed1b