| Subject | Re: [patch V4 part 3 04/29] x86/traps: Make interrupt enable/disable symmetric in C code | From | Alexandre Chartre <> | Date | Thu, 7 May 2020 17:25:56 +0200 |
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On 5/5/20 3:43 PM, Thomas Gleixner wrote: > Traps enable interrupts conditionally but rely on the ASM return code to > disable them again. That results in redundant interrupt disable and trace > calls. > > Make the trap handlers disable interrupts before returning to avoid that, > which allows simplification of the ASM entry code. > > Originally-by: Peter Zijlstra <peterz@infradead.org> > Signed-off-by: Thomas Gleixner <tglx@linutronix.de> > > --- > arch/x86/kernel/traps.c | 28 +++++++++++++++++++--------- > arch/x86/mm/fault.c | 15 +++++++++++++-- > 2 files changed, 32 insertions(+), 11 deletions(-) >
So this patch makes C trap handlers disable interrupts on return but there's no change to the ASM entry code, which will still (also) disable interrupts. I suppose this is cleaned up in a next patch. So it's worth mentioning that the "simplification of the ASM entry code" is not in this patch.
alex.
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