diff options
| author | Kevin Hilman <khilman@ti.com> | 2011-08-05 21:45:20 +0200 |
|---|---|---|
| committer | Rafael J. Wysocki <rjw@sisk.pl> | 2011-08-05 21:45:20 +0200 |
| commit | 02b26774afebb2d62695ba3230319d70d8c6cc2d (patch) | |
| tree | 956c4056fcb42d2c2b2a75e20d3ad98f148865fc /drivers/misc/atmel_tclib.c | |
| parent | fe202fde50a986a8510c62a76dc8733c1a8fac86 (diff) | |
PM / Runtime: Allow _put_sync() from interrupts-disabled context
Currently the use of pm_runtime_put_sync() is not safe from
interrupts-disabled context because rpm_idle() will release the
spinlock and enable interrupts for the idle callbacks. This enables
interrupts during a time where interrupts were expected to be
disabled, and can have strange side effects on drivers that expected
interrupts to be disabled.
This is not a bug since the documentation clearly states that only
_put_sync_suspend() is safe in IRQ-safe mode.
However, pm_runtime_put_sync() could be made safe when in IRQ-safe
mode by releasing the spinlock but not re-enabling interrupts, which
is what this patch aims to do.
Problem was found when using some buggy drivers that set
pm_runtime_irq_safe() and used _put_sync() in interrupts-disabled
context.
Reported-by: Colin Cross <ccross@google.com>
Tested-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Diffstat (limited to 'drivers/misc/atmel_tclib.c')
0 files changed, 0 insertions, 0 deletions