Messages in this thread Patch in this message | | | From | Jia-Ju Bai <> | Subject | [PATCH V2] hid: hid-core: Fix a sleep-in-atomic-context bug in __hid_request() | Date | Thu, 13 Sep 2018 11:34:32 +0800 |
| |
hid_alloc_report_buf() has to be called with GFP_ATOMIC in __hid_request(), because there are the following callchains leading to __hid_request() being an atomic context:
picolcd_send_and_wait (acquire a spinlock) hid_hw_request __hid_request hid_alloc_report_buf(GFP_KERNEL)
picolcd_reset (acquire a spinlock) hid_hw_request __hid_request hid_alloc_report_buf(GFP_KERNEL)
lg4ff_play (acquire a spinlock) hid_hw_request __hid_request hid_alloc_report_buf(GFP_KERNEL)
lg4ff_set_autocenter_ffex (acquire a spinlock) hid_hw_request __hid_request hid_alloc_report_buf(GFP_KERNEL)
This bug is found by my static analysis tool DSAC.
Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com> --- v2: * Make the description more human readable. Thanks Jiri for good advice. --- drivers/hid/hid-core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c index 3942ee61bd1c..c886af00c8c9 100644 --- a/drivers/hid/hid-core.c +++ b/drivers/hid/hid-core.c @@ -1442,7 +1442,7 @@ void __hid_request(struct hid_device *hid, struct hid_report *report, int ret; u32 len; - buf = hid_alloc_report_buf(report, GFP_KERNEL); + buf = hid_alloc_report_buf(report, GFP_ATOMIC); if (!buf) return; -- 2.17.0
| |