From: Sasha Neftin sasha.neftin@intel.com
[ Upstream commit 907862e9aef75bf89e2b265efcc58870be06081e ]
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: c0071c7aa5fe ("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 --- drivers/net/ethernet/intel/igc/igc_i225.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ethernet/intel/igc/igc_i225.c b/drivers/net/ethernet/intel/igc/igc_i225.c index b6807e16eea9..a0e2a404d535 100644 --- a/drivers/net/ethernet/intel/igc/igc_i225.c +++ b/drivers/net/ethernet/intel/igc/igc_i225.c @@ -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;