Re: [PATCH/RFC] Change the program check exception from EXC_XFER_STD to EXC_XFER_EE.
From: Kumar Gala <hidden>
Date: 2006-12-06 21:59:49
On Dec 6, 2006, at 3:50 PM, Scott Wood wrote:
This patch causes interrupts to be enabled in program_check_exception() if they were enabled in the faulting context. This is required because do_mathemu() calls get_user(), which can sleep, and thus triggers an assertion if called with interrupts disabled. Signed-off-by: Scott Wood <redacted> --- Is there any reason why ProgramCheck needs to be EXC_XFER_STD? Has nobody ever used math emulation with CONFIG_DEBUG_SPINLOCK_SLEEP before?
This has come up before and I think our desired solution is to use use local_irq_enable() in traps.c. For some reason we didn't realize that we needed to fix the do_mathemu() path. Take a look at the following threads: http://lkml.org/lkml/2006/2/22/243 http://ozlabs.org/pipermail/linuxppc-dev/2006-August/025016.html http://git.kernel.org/git/?p=linux/kernel/git/paulus/ powerpc.git;a=commitdiff;h=cd8a5673e9abb3fde0a1c25ee63a60fe1908c6f5 - kumar