]> git.baikalelectronics.ru Git - kernel.git/commit
um: Prevent IRQ handler reentrancy
authorAnton Ivanov <aivanov@brocade.com>
Mon, 21 Dec 2015 11:28:02 +0000 (11:28 +0000)
committerRichard Weinberger <richard@nod.at>
Sun, 10 Jan 2016 20:49:47 +0000 (21:49 +0100)
commit03ff59a391e8d7a516deccaed2c8c9cf402900f5
tree7f40e2da3a070e811a412865ffbf5c317844e257
parentfa02cd576bf056fc5e34c38a5e33b01d9cd33f70
um: Prevent IRQ handler reentrancy

The existing IRQ handler design in UML does not prevent reentrancy

This is mitigated by fd-enable/fd-disable semantics for the IO
portion of the UML subsystem. The timer, however, can and is
re-entered resulting in very deep stack usage and occasional
stack exhaustion.

This patch prevents this by checking if there is a timer
interrupt in-flight before processing any pending timer interrupts.

Signed-off-by: Anton Ivanov <aivanov@brocade.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
arch/um/os-Linux/signal.c