For reference's sake, one patch that does not seem to be the culprit:
From the list of 2.6.39 changes at kernelnewbies.org, the one IRQ-related change I could pick out was this:
genirq: Provide forced interrupt threading
http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=8d32a307e4faa8b123dc8a9cd56d1a7525f69ad3
I built a 2.6.39 with that patch reverted. It made no difference; the regression was present.
For reference's sake, one patch that does not seem to be the culprit:
From the list of 2.6.39 changes at kernelnewbies.org, the one IRQ-related change I could pick out was this:
genirq: Provide forced interrupt threading
http:// git.kernel. org/?p= linux/kernel/ git/torvalds/ linux-2. 6.git;a= commitdiff; h=8d32a307e4faa 8b123dc8a9cd56d 1a7525f69ad3
I built a 2.6.39 with that patch reverted. It made no difference; the regression was present.