Doing 'WARN_ON(preempt_count())' was horribly horribly wrong, and would cause tons of warnings at bootup if PREEMPT was enabled because the initcalls currently run with the kernel lock, which increments the preempt count. At the same time, the warning was also insufficient, since it didn't check that interrupts were enabled. The proper debug function to use for something that can sleep and wants a warning if it's called in the wrong context is 'might_sleep()'. Reported-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch adds a mutex to the e1000e driver that would help catch any collisions of two e1000e threads accessing hardware at the same time. description and patch updated by Jesse Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
the stats lock is left over from e1000, e1000e no longer has the adjust tbi stats function that required the addition of the stats lock to begin with. adding a mutex to acquire_swflag helped catch this one too. Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
thanks to tglx, we're finding some interesting reentrancy issues. this patch removes the phy read from inside a spinlock, paving the way for removing the spinlock completely. The phy read was only feeding a statistic that wasn't used. Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
e1000e was apparently calling two functions that attempted to reserve the SWFLAG bit for exclusive (to hardware and firmware) access to the PHY and NVM (aka eeprom). These accesses could possibly call msleep to wait for the resource which is not allowed from interrupt context. Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
in the process of debugging things, noticed that the swflag is not reset by the driver after reset, and the swflag is probably not reset unless management firmware clears it after 100ms. Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Set the hardware to ignore all write/erase cycles to the GbE region in the ICHx NVM. This feature can be disabled by the WriteProtectNVM module parameter (enabled by default) only after a hardware reset, but the machine must be power cycled before trying to enable writes. Signed-off-by: Bruce Allan <bruce.w.allan@intel.com> Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com> CC: arjan@linux.intel.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Enabling the MIB interrupts has proven to cause an interrupt storm after 7 hours of run. We will make use of the MIB interrupt once we have ANI supported added so for now to cure this we disable the interrupt. The interrupt storm can be seen as follows after 7 hours of run as reported by Steven Noonan <steven@uplinklabs.net>: 18:28:38 sum 1106.00 18:28:39 sum 1037.62 18:28:40 sum 1069.00 18:28:41 sum 1167.00 18:28:42 sum 1155.00 18:28:43 sum 1339.00 18:28:44 sum 18355.00 18:28:45 sum 17845.45 18:28:46 sum 15285.00 18:28:47 sum 17511.00 18:28:48 sum 17568.69 18:28:49 sum 17704.04 18:28:50 sum 18566.67 18:28:51 sum 18913.13 at 18:28:44 the MIB interrupt kicked off and caused huge latency which can be seen even on a video he submitted: http://www.youtube.com/watch?v=4GeCx1gZMpA Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>