Commit-ID: 5eca7453d61003bf886992388f8cb407e6f0d051 Gitweb: http://git.kernel.org/tip/5eca7453d61003bf886992388f8cb407e6f0d051 Author: Wang Nan <wangn...@huawei.com> AuthorDate: Fri, 27 Feb 2015 12:19:49 +0800 Committer: Ingo Molnar <mi...@kernel.org> CommitDate: Thu, 5 Mar 2015 00:47:29 +0100
x86/traps: Separate set_intr_gate() and clean up early_trap_init() As early_trap_init() doesn't use IST, replace set_intr_gate_ist() and set_system_intr_gate_ist() with their standard counterparts. set_intr_gate() requires a trace_debug symbol which we don't have and won't use. This patch separates set_intr_gate() into two parts, and uses base version in early_trap_init(). Reported-by: Andy Lutomirski <l...@amacapital.net> Signed-off-by: Wang Nan <wangn...@huawei.com> Acked-by: Andy Lutomirski <l...@amacapital.net> Cc: <dave.han...@linux.intel.com> Cc: <lize...@huawei.com> Cc: <masami.hiramatsu...@hitachi.com> Cc: <o...@redhat.com> Cc: <rost...@goodmis.org> Cc: Borislav Petkov <b...@alien8.de> Cc: H. Peter Anvin <h...@zytor.com> Cc: Thomas Gleixner <t...@linutronix.de> Link: http://lkml.kernel.org/r/1425010789-13714-1-git-send-email-wangn...@huawei.com Signed-off-by: Ingo Molnar <mi...@kernel.org> --- arch/x86/include/asm/desc.h | 7 ++++++- arch/x86/kernel/traps.c | 20 ++++++++++++-------- 2 files changed, 18 insertions(+), 9 deletions(-) diff --git a/arch/x86/include/asm/desc.h b/arch/x86/include/asm/desc.h index a94b82e..a0bf89f 100644 --- a/arch/x86/include/asm/desc.h +++ b/arch/x86/include/asm/desc.h @@ -376,11 +376,16 @@ static inline void _set_gate(int gate, unsigned type, void *addr, * Pentium F0 0F bugfix can have resulted in the mapped * IDT being write-protected. */ -#define set_intr_gate(n, addr) \ +#define set_intr_gate_notrace(n, addr) \ do { \ BUG_ON((unsigned)n > 0xFF); \ _set_gate(n, GATE_INTERRUPT, (void *)addr, 0, 0, \ __KERNEL_CS); \ + } while (0) + +#define set_intr_gate(n, addr) \ + do { \ + set_intr_gate_notrace(n, addr); \ _trace_set_gate(n, GATE_INTERRUPT, (void *)trace_##addr,\ 0, 0, __KERNEL_CS); \ } while (0) diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c index 4281988..9965bd1 100644 --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -926,16 +926,20 @@ dotraplinkage void do_iret_error(struct pt_regs *regs, long error_code) void __init early_trap_init(void) { /* - * Don't set ist to DEBUG_STACK as it doesn't work until TSS is - * ready in cpu_init() <-- trap_init(). Before trap_init(), CPU - * runs at ring 0 so it is impossible to hit an invalid stack. - * Using the original stack works well enough at this early - * stage. DEBUG_STACK will be equipped after cpu_init() in + * Don't use IST to set DEBUG_STACK as it doesn't work until TSS + * is ready in cpu_init() <-- trap_init(). Before trap_init(), + * CPU runs at ring 0 so it is impossible to hit an invalid + * stack. Using the original stack works well enough at this + * early stage. DEBUG_STACK will be equipped after cpu_init() in * trap_init(). + * + * We don't need to set trace_idt_table like set_intr_gate(), + * since we don't have trace_debug and it will be reset to + * 'debug' in trap_init() by set_intr_gate_ist(). */ - set_intr_gate_ist(X86_TRAP_DB, &debug, 0); + set_intr_gate_notrace(X86_TRAP_DB, debug); /* int3 can be called from all */ - set_system_intr_gate_ist(X86_TRAP_BP, &int3, 0); + set_system_intr_gate(X86_TRAP_BP, &int3); #ifdef CONFIG_X86_32 set_intr_gate(X86_TRAP_PF, page_fault); #endif @@ -1015,7 +1019,7 @@ void __init trap_init(void) /* * X86_TRAP_DB and X86_TRAP_BP have been set - * in early_trap_init(). However, DEBUG_STACK works only after + * in early_trap_init(). However, ITS works only after * cpu_init() loads TSS. See comments in early_trap_init(). */ set_intr_gate_ist(X86_TRAP_DB, &debug, DEBUG_STACK); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
