From 41591a51f00d2dc7bb9dc6e9bedf56c5cf6f2392 Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Thu, 31 Oct 2019 13:53:41 +0300 Subject: [PATCH] iocost: don't nest spin_lock_irq in ioc_weight_write() This code causes a static analysis warning: block/blk-iocost.c:2113 ioc_weight_write() error: double lock 'irq' We disable IRQs in blkg_conf_prep() and re-enable them in blkg_conf_finish(). IRQ disable/enable should not be nested because that means the IRQs will be enabled at the first unlock instead of the second one. Fixes: 7caa47151ab2 ("blkcg: implement blk-iocost") Acked-by: Tejun Heo Signed-off-by: Dan Carpenter Signed-off-by: Jens Axboe --- block/blk-iocost.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/block/blk-iocost.c b/block/blk-iocost.c index 2a3db80..a7ed434 100644 --- a/block/blk-iocost.c +++ b/block/blk-iocost.c @@ -2110,10 +2110,10 @@ static ssize_t ioc_weight_write(struct kernfs_open_file *of, char *buf, goto einval; } - spin_lock_irq(&iocg->ioc->lock); + spin_lock(&iocg->ioc->lock); iocg->cfg_weight = v; weight_updated(iocg); - spin_unlock_irq(&iocg->ioc->lock); + spin_unlock(&iocg->ioc->lock); blkg_conf_finish(&ctx); return nbytes; -- 2.7.4