igc: Fix infinite loop in release_swfw_sync

[ Upstream commit 907862e9ae ]

An infinite loop may occur if we fail to acquire the HW semaphore,
which is needed for resource release.
This will typically happen if the hardware is surprise-removed.
At this stage there is nothing to do, except log an error and quit.

Fixes: c0071c7aa5 ("igc: Add HW initialization code")
Suggested-by: Dima Ruinskiy <dima.ruinskiy@intel.com>
Signed-off-by: Sasha Neftin <sasha.neftin@intel.com>
Tested-by: Naama Meir <naamax.meir@linux.intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Sasha Neftin 2022-03-01 15:32:10 +02:00 committed by Greg Kroah-Hartman
parent c222c9291b
commit 8c78521411

View file

@ -156,8 +156,15 @@ void igc_release_swfw_sync_i225(struct igc_hw *hw, u16 mask)
{
u32 swfw_sync;
while (igc_get_hw_semaphore_i225(hw))
; /* Empty */
/* Releasing the resource requires first getting the HW semaphore.
* If we fail to get the semaphore, there is nothing we can do,
* except log an error and quit. We are not allowed to hang here
* indefinitely, as it may cause denial of service or system crash.
*/
if (igc_get_hw_semaphore_i225(hw)) {
hw_dbg("Failed to release SW_FW_SYNC.\n");
return;
}
swfw_sync = rd32(IGC_SW_FW_SYNC);
swfw_sync &= ~mask;