b831236509
The ethtool API for obtaining device statistics is not intended to allow runtime changes in the number of statistics reported. It may *appear* this way, as there is an ability to request the number of stats using ethtool_get_set_count(). However, it is expected that this must always return the same value for invocations of the same device. If we don't satisfy this contract, and allow the number of stats to change during run time, we could cause invalid memory accesses or report the stat strings incorrectly. This is because the API for obtaining stats is to (1) get the size, (2) get the strings and finally (3) get the stats. Since these are each separate ethtool op commands, it is not possible to maintain consistency by holding the RTNL lock over the whole operation. This results in the potential for a race condition to occur where the size changed between any of the 3 calls. Avoid this issue by requiring that we always return the same value for a given device. We can check any values which remain constant for the life of the device, but must not report different sizes depending on runtime attributes. This patch specifically fixes the queue statistics to always return every queue even if it's not currently in use. Signed-off-by: Jacob Keller <jacob.e.keller@intel.com> Tested-by: Andrew Bowers <andrewx.bowers@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> |
||
|---|---|---|
| .. | ||
| e1000 | ||
| e1000e | ||
| fm10k | ||
| i40e | ||
| i40evf | ||
| ice | ||
| igb | ||
| igbvf | ||
| ixgb | ||
| ixgbe | ||
| ixgbevf | ||
| e100.c | ||
| Kconfig | ||
| Makefile | ||