Bug 220235 - sys/dev/aacraid/aacraid.c: A sleep-under-mutex bug in aac_alloc_commands
Summary: sys/dev/aacraid/aacraid.c: A sleep-under-mutex bug in aac_alloc_commands
Status: New
Alias: None
Product: Base System
Classification: Unclassified
Component: kern (show other bugs)
Version: CURRENT
Hardware: Any Any
: --- Affects Only Me
Assignee: freebsd-bugs (Nobody)
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2017-06-24 03:06 UTC by Jia-Ju Bai
Modified: 2017-06-24 03:06 UTC (History)
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Description Jia-Ju Bai 2017-06-24 03:06:03 UTC 
The driver may sleep under a mutex, and the code path is:
aac_alloc_commands [line 1223: acquire the mutex]
aac_alloc_commands [line 1227]
  bus_dmamap_create(BUS_DMA_WAITOK) [line 1250] --> may sleep

The possible fix of this bug is to replace the "BUS_DMA_WAITOK" in bus_dmamap_create with "BUS_DMA_NOWAIT".

This bug is found by a static analysis tool written by myself, and it is checked by my review of the FreeBSD code.