On 06/18/17 11:52, Jia-Ju Bai wrote:
The driver may sleep under a mutex, and the code path is: acpi_tz_thread [line 992: acquire the mutex] acpi_tz_thread [line 993] acpi_tz_thread [line 1003] acpi_tz_thread [line 1004] (msleep is excuted) acpi_tz_thread [line 1008] acpi_tz_thread [line 970] acpi_tz_thread [line 971] acpi_tz_thread [line 975] malloc(M_WAITOK) [line 976]The possible fix of this bug is to replace "M_WAITOK" in malloc with "M_NOWAIT". This bug is found by a static analysis tool written by myself, and it is checked by my review of the FreeBSD code. Signed-off-by: Jia-Ju Bai <baijiaju1...@163.com> --- sys/dev/acpica/acpi_thermal.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/sys/dev/acpica/acpi_thermal.c b/sys/dev/acpica/acpi_thermal.c index b2b2a13aa88..fb9f44b5711 100644 --- a/sys/dev/acpica/acpi_thermal.c +++ b/sys/dev/acpica/acpi_thermal.c @@ -974,7 +974,7 @@ acpi_tz_thread(void *arg) } devclass_get_devices(acpi_tz_devclass, &devs, &devcount); sc = malloc(sizeof(struct acpi_tz_softc *) * devcount, M_TEMP, - M_WAITOK | M_ZERO); + M_NOWAIT | M_ZERO); for (i = 0; i < devcount; i++) sc[i] = device_get_softc(devs[i]); }
If you change to M_NOWAIT you need to add code to check if sc == NULL. --HPS _______________________________________________ freebsd-acpi@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-acpi To unsubscribe, send any mail to "freebsd-acpi-unsubscr...@freebsd.org"
