On Sunday, 30 September 2007 20:39, Alexey Starikovskiy wrote: > ACPI uses acpi_get_register() in order to get into suspend. > This function is guarded by acpi_gbl_hardware_lock, which will be carried > into resume phase. > At resume interrupts are enabled and first ACPI interrupt deadlocks on this > lock. Ouch. That might have bitten quite some people, I guess. > Solution seems to be to not lock register read, as there are no concurrent > activity at this point. > > Reference: http://bugzilla.kernel.org/show_bug.cgi?id=7499 > > Signed-off-by: Alexey Starikovskiy <astarikovskiy@xxxxxxx> Do you think it's -stable material? Greetings, Rafael > --- > > drivers/acpi/hardware/hwsleep.c | 3 ++- > include/acpi/acpixf.h | 2 ++ > 2 files changed, 4 insertions(+), 1 deletions(-) > > diff --git a/drivers/acpi/hardware/hwsleep.c b/drivers/acpi/hardware/hwsleep.c > index 4d0c677..c0577ca 100644 > --- a/drivers/acpi/hardware/hwsleep.c > +++ b/drivers/acpi/hardware/hwsleep.c > @@ -398,7 +398,8 @@ acpi_status asmlinkage acpi_enter_sleep_state(u8 sleep_state) > /* Wait until we enter sleep state */ > > do { > - status = acpi_get_register(ACPI_BITREG_WAKE_STATUS, &in_value); > + status = acpi_get_register_unlocked(ACPI_BITREG_WAKE_STATUS, > + &in_value); > if (ACPI_FAILURE(status)) { > return_ACPI_STATUS(status); > } > diff --git a/include/acpi/acpixf.h b/include/acpi/acpixf.h > index 3d7ab9e..9512f04 100644 > --- a/include/acpi/acpixf.h > +++ b/include/acpi/acpixf.h > @@ -314,6 +314,8 @@ acpi_resource_to_address64(struct acpi_resource *resource, > */ > acpi_status acpi_get_register(u32 register_id, u32 * return_value); > > +acpi_status acpi_get_register_unlocked(u32 register_id, u32 *return_value); > + > acpi_status acpi_set_register(u32 register_id, u32 value); > > acpi_status > > - > To unsubscribe from this list: send the line "unsubscribe linux-acpi" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > > -- "Premature optimization is the root of all evil." - Donald Knuth - To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
