[cleanup] do_general_protection doesn't disable irq

From: Andrea Arcangeli (andrea_at_suse.de)
Date: 07/30/04

  • Next message: Benjamin Herrenschmidt: "[PATCH] ppc64: hash table races fixes" 
    Date:	Fri, 30 Jul 2004 04:53:49 +0200
To: Andrew Morton <akpm@osdl.org>

    A trap gate shouldn't affect the irq status at all.

    This should be a valid cleanup that removes a slightly confusing noop:

    Index: linux-2.5/arch/i386/kernel/traps.c
    ===================================================================
    RCS file: /home/andrea/crypto/cvs/linux-2.5/arch/i386/kernel/traps.c,v
    retrieving revision 1.77
    diff -u -p -r1.77 traps.c
    --- linux-2.5/arch/i386/kernel/traps.c 13 Jul 2004 18:02:33 -0000 1.77
    +++ linux-2.5/arch/i386/kernel/traps.c 30 Jul 2004 02:44:23 -0000
    @@ -431,9 +431,6 @@ DO_ERROR_INFO(17, SIGBUS, "alignment che
     
     asmlinkage void do_general_protection(struct pt_regs * regs, long error_code)
     {
    - if (regs->eflags & X86_EFLAGS_IF)
    - local_irq_enable();
    -
             if (regs->eflags & VM_MASK)
                     goto gp_in_vm86;
     

    Thanks to Karsten for noticing a trap gate doesn't actually enable irq
    by default either (offtopic issue with the above patch, but while
    reading the 2.6 code I found the above bit which just confused me more
    since it's a noop, either that or you meant to use set_intr_gate, not
    set_trap_gate on the do_general_protection handler, but it seems not
    needed to use a trap gate since a trap gate shouldn't enable irqs by
    default). Please correct me if wrong.

    thanks.
    -
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