On Fri, Jul 26, 2013 at 10:59:25AM -0400, Valdis.Kletnieks@vt.edu wrote:
On Fri, 26 Jul 2013 00:02:31 -0400, Kumar amit mehta said:
So leaving the hardware at the mercy of the application doesn't sound like a good practice. This __may__ compromise kernel stability too. Also think of this:
In what possible way does it compromise kernel stability?
Sorry for forgetting that we are talking about userspace programs. Recently I came across an old HBA driver, which for some reason failed to properly intialize the firmware(maybe someone didn't properly copied the firmware in the /lib/firmware directory, i don't know) and because of that the firmware initialization code tried the same thing for a couple of iteration, failiing which it tried to reset the board, but somewhere during this recovery process started disabling the interrupt on the CPU. Later, watchdog timer kicked in, considering this as hard lock up and issued a system reset. When I first saw the firmware initialization error, I thought what harm this could bring to my overall system other than the particular HBA turning into an unusable one, but It turned out to be much more disruptive. When I said "This __may__ compromise kernel stability too", I was thinking, something on those lines and completely forgot that we are currently in uspace. !!amit