• Andy Lutomirski's avatar
    x86/entry/32: Change INT80 to be an interrupt gate · a798f091
    Andy Lutomirski authored
    We want all of the syscall entries to run with interrupts off so that
    we can efficiently run context tracking before enabling interrupts.
    
    This will regress int $0x80 performance on 32-bit kernels by a
    couple of cycles.  This shouldn't matter much -- int $0x80 is not a
    fast path.
    
    This effectively reverts:
    
      657c1eea ("x86/entry/32: Fix entry_INT80_32() to expect interrupts to be on")
    
    ... and fixes the same issue differently.
    Signed-off-by: default avatarAndy Lutomirski <luto@kernel.org>
    Cc: Andy Lutomirski <luto@amacapital.net>
    Cc: Borislav Petkov <bp@alien8.de>
    Cc: Brian Gerst <brgerst@gmail.com>
    Cc: Denys Vlasenko <dvlasenk@redhat.com>
    Cc: Frédéric Weisbecker <fweisbec@gmail.com>
    Cc: H. Peter Anvin <hpa@zytor.com>
    Cc: Linus Torvalds <torvalds@linux-foundation.org>
    Cc: Paolo Bonzini <pbonzini@redhat.com>
    Cc: Peter Zijlstra <peterz@infradead.org>
    Cc: Rik van Riel <riel@redhat.com>
    Cc: Thomas Gleixner <tglx@linutronix.de>
    Link: http://lkml.kernel.org/r/59b4f90c9ebfccd8c937305dbbbca680bc74b905.1457558566.git.luto@kernel.orgSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
    a798f091
traps.c 26 KB