From 2f766d16062d0147edff91be15de4a950667ca42 Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Tue, 26 Sep 2006 10:52:28 +0200 Subject: [PATCH] Clean up asm/smp.h includes No need to include it from entry.S Drop all the #ifdef __ASSEMBLY__ Signed-off-by: Andi Kleen --- arch/x86_64/kernel/entry.S | 2 -- 1 file changed, 2 deletions(-) (limited to 'arch/x86_64/kernel/entry.S') diff --git a/arch/x86_64/kernel/entry.S b/arch/x86_64/kernel/entry.S index aa8d8939abc1..7eb1678e098d 100644 --- a/arch/x86_64/kernel/entry.S +++ b/arch/x86_64/kernel/entry.S @@ -27,10 +27,8 @@ * - schedule it carefully for the final hardware. */ -#define ASSEMBLY 1 #include #include -#include #include #include #include -- cgit v1.2.3 From b06babac45e1546dfb504f1f25eb0495632bfc41 Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Tue, 26 Sep 2006 10:52:29 +0200 Subject: [PATCH] Add proper alignment to ENTRY Previously it didn't align. Use the same one as the C compiler in blended mode, which is good for K8 and Core2 and doesn't hurt on P4. Signed-off-by: Andi Kleen --- arch/x86_64/kernel/entry.S | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'arch/x86_64/kernel/entry.S') diff --git a/arch/x86_64/kernel/entry.S b/arch/x86_64/kernel/entry.S index 7eb1678e098d..2dc5c01f754d 100644 --- a/arch/x86_64/kernel/entry.S +++ b/arch/x86_64/kernel/entry.S @@ -617,8 +617,7 @@ retint_signal: #ifdef CONFIG_PREEMPT /* Returning to kernel space. Check if we need preemption */ /* rcx: threadinfo. interrupts off. */ - .p2align -retint_kernel: +ENTRY(retint_kernel) cmpl $0,threadinfo_preempt_count(%rcx) jnz retint_restore_args bt $TIF_NEED_RESCHED,threadinfo_flags(%rcx) -- cgit v1.2.3 From 7f11d8a5efd625ffa41cde1d8472f85e885478ec Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Tue, 26 Sep 2006 10:52:29 +0200 Subject: [PATCH] Remove all ifdefs for local/io apic IO-APIC or local APIC can only be disabled at runtime anyways and Kconfig has forced these options on for a long time now. The Kconfigs are kept only now for the benefit of the shared acpi boot.c code. Signed-off-by: Andi Kleen --- arch/x86_64/kernel/entry.S | 2 -- 1 file changed, 2 deletions(-) (limited to 'arch/x86_64/kernel/entry.S') diff --git a/arch/x86_64/kernel/entry.S b/arch/x86_64/kernel/entry.S index 2dc5c01f754d..a0cf36ba7c56 100644 --- a/arch/x86_64/kernel/entry.S +++ b/arch/x86_64/kernel/entry.S @@ -676,7 +676,6 @@ ENTRY(call_function_interrupt) END(call_function_interrupt) #endif -#ifdef CONFIG_X86_LOCAL_APIC ENTRY(apic_timer_interrupt) apicinterrupt LOCAL_TIMER_VECTOR,smp_apic_timer_interrupt END(apic_timer_interrupt) @@ -688,7 +687,6 @@ END(error_interrupt) ENTRY(spurious_interrupt) apicinterrupt SPURIOUS_APIC_VECTOR,smp_spurious_interrupt END(spurious_interrupt) -#endif /* * Exception entry points. -- cgit v1.2.3 From 2e91a17b35116885373e04af142b1d08cf1b47bf Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Tue, 26 Sep 2006 10:52:29 +0200 Subject: [PATCH] Add some comments to entry.S And remove some old obsolete ones. Signed-off-by: Andi Kleen --- arch/x86_64/kernel/entry.S | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) (limited to 'arch/x86_64/kernel/entry.S') diff --git a/arch/x86_64/kernel/entry.S b/arch/x86_64/kernel/entry.S index a0cf36ba7c56..a04fc4108ff2 100644 --- a/arch/x86_64/kernel/entry.S +++ b/arch/x86_64/kernel/entry.S @@ -22,9 +22,21 @@ * at the top of the kernel process stack. * - partial stack frame: partially saved registers upto R11. * - full stack frame: Like partial stack frame, but all register saved. - * - * TODO: - * - schedule it carefully for the final hardware. + * + * Some macro usage: + * - CFI macros are used to generate dwarf2 unwind information for better + * backtraces. They don't change any code. + * - SAVE_ALL/RESTORE_ALL - Save/restore all registers + * - SAVE_ARGS/RESTORE_ARGS - Save/restore registers that C functions modify. + * There are unfortunately lots of special cases where some registers + * not touched. The macro is a big mess that should be cleaned up. + * - SAVE_REST/RESTORE_REST - Handle the registers not saved by SAVE_ARGS. + * Gives a full stack frame. + * - ENTRY/END Define functions in the symbol table. + * - FIXUP_TOP_OF_STACK/RESTORE_TOP_OF_STACK - Fix up the hardware stack + * frame that is otherwise undefined after a SYSCALL + * - TRACE_IRQ_* - Trace hard interrupt state for lock debugging. + * - errorentry/paranoidentry/zeroentry - Define exception entry points. */ #include -- cgit v1.2.3 From 44cc45267bbe7c64f7d85b074bd670b48b5abdfb Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Tue, 26 Sep 2006 10:52:31 +0200 Subject: [PATCH] Remove obsolete CVS $Id$ from assembler files in arch/x86_64/kernel/* CVS hasn't been used for a long time for them. Signed-off-by: Andi Kleen --- arch/x86_64/kernel/entry.S | 2 -- 1 file changed, 2 deletions(-) (limited to 'arch/x86_64/kernel/entry.S') diff --git a/arch/x86_64/kernel/entry.S b/arch/x86_64/kernel/entry.S index a04fc4108ff2..2092f565aa87 100644 --- a/arch/x86_64/kernel/entry.S +++ b/arch/x86_64/kernel/entry.S @@ -4,8 +4,6 @@ * Copyright (C) 1991, 1992 Linus Torvalds * Copyright (C) 2000, 2001, 2002 Andi Kleen SuSE Labs * Copyright (C) 2000 Pavel Machek - * - * $Id$ */ /* -- cgit v1.2.3 From d28c4393a7bf558538e9def269c1caeab6ec056f Mon Sep 17 00:00:00 2001 From: "Prasanna S.P" Date: Tue, 26 Sep 2006 10:52:34 +0200 Subject: [PATCH] x86: error_code is not safe for kprobes This patch moves the entry.S:error_entry to .kprobes.text section, since code marked unsafe for kprobes jumps directly to entry.S::error_entry, that must be marked unsafe as well. This patch also moves all the ".previous.text" asm directives to ".previous" for kprobes section. AK: Following a similar i386 patch from Chuck Ebbert AK: Also merged Jeremy's fix in. +From: Jeremy Fitzhardinge KPROBE_ENTRY does a .section .kprobes.text, and expects its users to do a .previous at the end of the function. Unfortunately, if any code within the function switches sections, for example .fixup, then the .previous ends up putting all subsequent code into .fixup. Worse, any subsequent .fixup code gets intermingled with the code its supposed to be fixing (which is also in .fixup). It's surprising this didn't cause more havok. The fix is to use .pushsection/.popsection, so this stuff nests properly. A further cleanup would be to get rid of all .section/.previous pairs, since they're inherently fragile. +From: Chuck Ebbert <76306.1226@compuserve.com> Because code marked unsafe for kprobes jumps directly to entry.S::error_code, that must be marked unsafe as well. The easiest way to do that is to move the page fault entry point to just before error_code and let it inherit the same section. Also moved all the ".previous" asm directives for kprobes sections to column 1 and removed ".text" from them. Signed-off-by: Chuck Ebbert <76306.1226@compuserve.com> Signed-off-by: Andi Kleen --- arch/x86_64/kernel/entry.S | 19 +++++++------------ 1 file changed, 7 insertions(+), 12 deletions(-) (limited to 'arch/x86_64/kernel/entry.S') diff --git a/arch/x86_64/kernel/entry.S b/arch/x86_64/kernel/entry.S index 2092f565aa87..780f9b26169f 100644 --- a/arch/x86_64/kernel/entry.S +++ b/arch/x86_64/kernel/entry.S @@ -819,7 +819,7 @@ paranoid_schedule\trace: * Exception entry point. This expects an error code/orig_rax on the stack * and the exception handler in %rax. */ -ENTRY(error_entry) +KPROBE_ENTRY(error_entry) _frame RDI /* rdi slot contains rax, oldrax contains error code */ cld @@ -903,7 +903,7 @@ error_kernelspace: cmpq $gs_change,RIP(%rsp) je error_swapgs jmp error_sti -END(error_entry) +KPROBE_END(error_entry) /* Reload gs selector with exception handling */ /* edi: new selector */ @@ -1025,8 +1025,7 @@ ENDPROC(execve) KPROBE_ENTRY(page_fault) errorentry do_page_fault -END(page_fault) - .previous .text +KPROBE_END(page_fault) ENTRY(coprocessor_error) zeroentry do_coprocessor_error @@ -1047,8 +1046,7 @@ KPROBE_ENTRY(debug) CFI_ADJUST_CFA_OFFSET 8 paranoidentry do_debug, DEBUG_STACK paranoidexit -END(debug) - .previous .text +KPROBE_END(debug) /* runs on exception stack */ KPROBE_ENTRY(nmi) @@ -1062,8 +1060,7 @@ KPROBE_ENTRY(nmi) jmp paranoid_exit1 CFI_ENDPROC #endif -END(nmi) - .previous .text +KPROBE_END(nmi) KPROBE_ENTRY(int3) INTR_FRAME @@ -1072,8 +1069,7 @@ KPROBE_ENTRY(int3) paranoidentry do_int3, DEBUG_STACK jmp paranoid_exit1 CFI_ENDPROC -END(int3) - .previous .text +KPROBE_END(int3) ENTRY(overflow) zeroentry do_overflow @@ -1121,8 +1117,7 @@ END(stack_segment) KPROBE_ENTRY(general_protection) errorentry do_general_protection -END(general_protection) - .previous .text +KPROBE_END(general_protection) ENTRY(alignment_check) errorentry do_alignment_check -- cgit v1.2.3 From 7a0a2dff1cac1df82acfa0395bc9bc1bf0bc16ef Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Tue, 26 Sep 2006 10:52:37 +0200 Subject: [PATCH] Add a missing check for irq flags tracing in NMI NMIs are not supposed to track the irq flags, but TRACE_IRQS_IRETQ did it anyways. Add a check. Cc: mingo@elte.hu Signed-off-by: Andi Kleen --- arch/x86_64/kernel/entry.S | 2 ++ 1 file changed, 2 insertions(+) (limited to 'arch/x86_64/kernel/entry.S') diff --git a/arch/x86_64/kernel/entry.S b/arch/x86_64/kernel/entry.S index 780f9b26169f..4fcc0ad8bbeb 100644 --- a/arch/x86_64/kernel/entry.S +++ b/arch/x86_64/kernel/entry.S @@ -773,7 +773,9 @@ paranoid_exit\trace: testl $3,CS(%rsp) jnz paranoid_userspace\trace paranoid_swapgs\trace: + .if \trace TRACE_IRQS_IRETQ 0 + .endif swapgs paranoid_restore\trace: RESTORE_ALL 8 -- cgit v1.2.3 From 96e540492ab54423f3693958329e095878f1f12b Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Tue, 26 Sep 2006 10:52:39 +0200 Subject: [PATCH] Fix a irqcount comment in entry.S Signed-off-by: Andi Kleen --- arch/x86_64/kernel/entry.S | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) (limited to 'arch/x86_64/kernel/entry.S') diff --git a/arch/x86_64/kernel/entry.S b/arch/x86_64/kernel/entry.S index 4fcc0ad8bbeb..ea32688386fd 100644 --- a/arch/x86_64/kernel/entry.S +++ b/arch/x86_64/kernel/entry.S @@ -519,7 +519,12 @@ END(stub_rt_sigreturn) testl $3,CS(%rdi) je 1f swapgs -1: incl %gs:pda_irqcount # RED-PEN should check preempt count + /* irqcount is used to check if a CPU is already on an interrupt + stack or not. While this is essentially redundant with preempt_count + it is a little cheaper to use a separate counter in the PDA + (short of moving irq_enter into assembly, which would be too + much work) */ +1: incl %gs:pda_irqcount cmoveq %gs:pda_irqstackptr,%rsp push %rbp # backlink for old unwinder /* -- cgit v1.2.3 From adf1423698f00d00b267f7dca8231340ce7d65ef Mon Sep 17 00:00:00 2001 From: Jan Beulich Date: Tue, 26 Sep 2006 10:52:41 +0200 Subject: [PATCH] i386/x86-64: Work around gcc bug with noreturn functions in unwinder Current gcc generates calls not jumps to noreturn functions. When that happens the return address can point to the next function, which confuses the unwinder. This patch works around it by marking asynchronous exception frames in contrast normal call frames in the unwind information. Then teach the unwinder to decode this. For normal call frames the unwinder now subtracts one from the address which avoids this problem. The standard libgcc unwinder uses the same trick. It doesn't include adjustment of the printed address (i.e. for the original example, it'd still be kernel_math_error+0 that gets displayed, but the unwinder wouldn't get confused anymore. This only works with binutils 2.6.17+ and some versions of H.J.Lu's 2.6.16 unfortunately because earlier binutils don't support .cfi_signal_frame [AK: added automatic detection of the new binutils and wrote description] Signed-off-by: Jan Beulich Signed-off-by: Andi Kleen --- arch/x86_64/kernel/entry.S | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'arch/x86_64/kernel/entry.S') diff --git a/arch/x86_64/kernel/entry.S b/arch/x86_64/kernel/entry.S index ea32688386fd..4cbc65290ae7 100644 --- a/arch/x86_64/kernel/entry.S +++ b/arch/x86_64/kernel/entry.S @@ -123,6 +123,7 @@ .macro CFI_DEFAULT_STACK start=1 .if \start CFI_STARTPROC simple + CFI_SIGNAL_FRAME CFI_DEF_CFA rsp,SS+8 .else CFI_DEF_CFA_OFFSET SS+8 @@ -207,6 +208,7 @@ END(ret_from_fork) ENTRY(system_call) CFI_STARTPROC simple + CFI_SIGNAL_FRAME CFI_DEF_CFA rsp,PDA_STACKOFFSET CFI_REGISTER rip,rcx /*CFI_REGISTER rflags,r11*/ @@ -324,6 +326,7 @@ END(system_call) */ ENTRY(int_ret_from_sys_call) CFI_STARTPROC simple + CFI_SIGNAL_FRAME CFI_DEF_CFA rsp,SS+8-ARGOFFSET /*CFI_REL_OFFSET ss,SS-ARGOFFSET*/ CFI_REL_OFFSET rsp,RSP-ARGOFFSET @@ -484,6 +487,7 @@ END(stub_rt_sigreturn) */ .macro _frame ref CFI_STARTPROC simple + CFI_SIGNAL_FRAME CFI_DEF_CFA rsp,SS+8-\ref /*CFI_REL_OFFSET ss,SS-\ref*/ CFI_REL_OFFSET rsp,RSP-\ref -- cgit v1.2.3 From 658fdbef66e5e9be79b457edc2cbbb3add840aa9 Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Tue, 26 Sep 2006 10:52:41 +0200 Subject: [PATCH] Don't leak NT bit into next task SYSENTER can cause a NT to be set which might cause crashes on the IRET in the next task. Following similar i386 patch from Linus. Signed-off-by: Andi Kleen --- arch/x86_64/kernel/entry.S | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'arch/x86_64/kernel/entry.S') diff --git a/arch/x86_64/kernel/entry.S b/arch/x86_64/kernel/entry.S index 4cbc65290ae7..2802524104f3 100644 --- a/arch/x86_64/kernel/entry.S +++ b/arch/x86_64/kernel/entry.S @@ -155,6 +155,10 @@ /* rdi: prev */ ENTRY(ret_from_fork) CFI_DEFAULT_STACK + push kernel_eflags(%rip) + CFI_ADJUST_CFA_OFFSET 4 + popf # reset kernel eflags + CFI_ADJUST_CFA_OFFSET -4 call schedule_tail GET_THREAD_INFO(%rcx) testl $(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT),threadinfo_flags(%rcx) -- cgit v1.2.3