----- commit a879cbbb34cbecfa9707fbb6e5a00c503ac1ecb9 tree fdf247f8dedea8f04d0989aeab6922ed073eee11 parent c06fec5022ebe014af876da2df4a0eee836e97c8 author Linus Torvalds <torvalds@ppc970.osdl.org> Fri, 29 Apr 2005 09:38:44 -0700 committer Linus Torvalds <torvalds@ppc970.osdl.org> Fri, 29 Apr 2005 09:38:44 -0700 x86: make traps on 'iret' be debuggable in user space This makes a trap on the 'iret' that returns us to user space cause a nice clean SIGSEGV, instead of just a hard (and silent) exit. That way a debugger can actually try to see what happened, and we also properly notify everybody who might be interested about us being gone. This loses the error code, but tells the debugger what happened with ILL_BADSTK in the siginfo. --- k/arch/i386/kernel/entry.S (mode:100644) +++ l/arch/i386/kernel/entry.S (mode:100644) @@ -260,11 +260,9 @@ restore_nocheck: .section .fixup,"ax" iret_exc: sti - movl $__USER_DS, %edx - movl %edx, %ds - movl %edx, %es - movl $11,%eax - call do_exit + pushl $0 # no error code + pushl $do_iret_error + jmp error_code .previous .section __ex_table,"a" .align 4 --- k/arch/i386/kernel/traps.c (mode:100644) +++ l/arch/i386/kernel/traps.c (mode:100644) @@ -451,6 +451,7 @@ DO_ERROR(10, SIGSEGV, "invalid TSS", inv DO_ERROR(11, SIGBUS, "segment not present", segment_not_present) DO_ERROR(12, SIGBUS, "stack segment", stack_segment) DO_ERROR_INFO(17, SIGBUS, "alignment check", alignment_check, BUS_ADRALN, 0) +DO_ERROR_INFO(32, SIGSEGV, "iret exception", iret_error, ILL_BADSTK, 0) fastcall void do_general_protection(struct pt_regs * regs, long error_code) { - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/