From 0f5340933f9bacb403f49baaf8073320e3984841 Mon Sep 17 00:00:00 2001 From: Roland McGrath Date: Wed, 30 Jan 2008 13:30:59 +0100 Subject: [PATCH] x86: x86-32 thread_struct.debugreg This replaces the debugreg[7] member of thread_struct with individual members debugreg0, etc. This saves two words for the dummies 4 and 5, and harmonizes the code between 32 and 64. Signed-off-by: Roland McGrath Signed-off-by: Ingo Molnar Signed-off-by: Thomas Gleixner --- arch/x86/kernel/process_32.c | 31 ++++++++++++++++++++----------- arch/x86/kernel/ptrace_32.c | 29 ++++++++++++++++++++++++----- arch/x86/kernel/signal_32.c | 4 ++-- arch/x86/kernel/traps_32.c | 4 ++-- arch/x86/power/cpu.c | 14 +++++++------- include/asm-x86/processor_32.h | 7 ++++++- 6 files changed, 61 insertions(+), 28 deletions(-) diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c index 5340646..3744cf6 100644 --- a/arch/x86/kernel/process_32.c +++ b/arch/x86/kernel/process_32.c @@ -445,7 +445,12 @@ void flush_thread(void) { struct task_struct *tsk = current; - memset(tsk->thread.debugreg, 0, sizeof(unsigned long)*8); + tsk->thread.debugreg0 = 0; + tsk->thread.debugreg1 = 0; + tsk->thread.debugreg2 = 0; + tsk->thread.debugreg3 = 0; + tsk->thread.debugreg6 = 0; + tsk->thread.debugreg7 = 0; memset(tsk->thread.tls_array, 0, sizeof(tsk->thread.tls_array)); clear_tsk_thread_flag(tsk, TIF_DEBUG); /* @@ -522,7 +527,6 @@ int copy_thread(int nr, unsigned long clone_flags, unsigned long sp, */ void dump_thread(struct pt_regs * regs, struct user * dump) { - int i; u16 gs; /* changed the size calculations - should hopefully work better. lbt */ @@ -533,8 +537,14 @@ void dump_thread(struct pt_regs * regs, struct user * dump) dump->u_dsize = ((unsigned long) (current->mm->brk + (PAGE_SIZE-1))) >> PAGE_SHIFT; dump->u_dsize -= dump->u_tsize; dump->u_ssize = 0; - for (i = 0; i < 8; i++) - dump->u_debugreg[i] = current->thread.debugreg[i]; + dump->u_debugreg[0] = current->thread.debugreg0; + dump->u_debugreg[1] = current->thread.debugreg1; + dump->u_debugreg[2] = current->thread.debugreg2; + dump->u_debugreg[3] = current->thread.debugreg3; + dump->u_debugreg[4] = 0; + dump->u_debugreg[5] = 0; + dump->u_debugreg[6] = current->thread.debugreg6; + dump->u_debugreg[7] = current->thread.debugreg7; if (dump->start_stack < TASK_SIZE) dump->u_ssize = ((unsigned long) (TASK_SIZE - dump->start_stack)) >> PAGE_SHIFT; @@ -612,13 +622,13 @@ __switch_to_xtra(struct task_struct *prev_p, struct task_struct *next_p, wrmsr(MSR_IA32_DEBUGCTLMSR, next->debugctlmsr, 0); if (test_tsk_thread_flag(next_p, TIF_DEBUG)) { - set_debugreg(next->debugreg[0], 0); - set_debugreg(next->debugreg[1], 1); - set_debugreg(next->debugreg[2], 2); - set_debugreg(next->debugreg[3], 3); + set_debugreg(next->debugreg0, 0); + set_debugreg(next->debugreg1, 1); + set_debugreg(next->debugreg2, 2); + set_debugreg(next->debugreg3, 3); /* no 4 and 5 */ - set_debugreg(next->debugreg[6], 6); - set_debugreg(next->debugreg[7], 7); + set_debugreg(next->debugreg6, 6); + set_debugreg(next->debugreg7, 7); } #ifdef CONFIG_SECCOMP @@ -869,4 +879,3 @@ unsigned long arch_randomize_brk(struct mm_struct *mm) unsigned long range_end = mm->brk + 0x02000000; return randomize_range(mm->brk, range_end, 0) ? : mm->brk; } - diff --git a/arch/x86/kernel/ptrace_32.c b/arch/x86/kernel/ptrace_32.c index 2607130..fed83d0 100644 --- a/arch/x86/kernel/ptrace_32.c +++ b/arch/x86/kernel/ptrace_32.c @@ -133,19 +133,39 @@ static unsigned long getreg(struct task_struct *child, unsigned long regno) */ static unsigned long ptrace_get_debugreg(struct task_struct *child, int n) { - return child->thread.debugreg[n]; + switch (n) { + case 0: return child->thread.debugreg0; + case 1: return child->thread.debugreg1; + case 2: return child->thread.debugreg2; + case 3: return child->thread.debugreg3; + case 6: return child->thread.debugreg6; + case 7: return child->thread.debugreg7; + } + return 0; } static int ptrace_set_debugreg(struct task_struct *child, int n, unsigned long data) { + int i; + if (unlikely(n == 4 || n == 5)) return -EIO; if (n < 4 && unlikely(data >= TASK_SIZE - 3)) return -EIO; - if (n == 7) { + switch (n) { + case 0: child->thread.debugreg0 = data; break; + case 1: child->thread.debugreg1 = data; break; + case 2: child->thread.debugreg2 = data; break; + case 3: child->thread.debugreg3 = data; break; + + case 6: + child->thread.debugreg6 = data; + break; + + case 7: /* * Sanity-check data. Take one half-byte at once with * check = (val >> (16 + 4*i)) & 0xf. It contains the @@ -176,19 +196,18 @@ static int ptrace_set_debugreg(struct task_struct *child, * 64-bit kernel), so the x86_64 mask value is 0x5454. * See the AMD manual no. 24593 (AMD64 System Programming) */ - int i; data &= ~DR_CONTROL_RESERVED; for (i = 0; i < 4; i++) if ((0x5f54 >> ((data >> (16 + 4*i)) & 0xf)) & 1) return -EIO; + child->thread.debugreg7 = data; if (data) set_tsk_thread_flag(child, TIF_DEBUG); else clear_tsk_thread_flag(child, TIF_DEBUG); + break; } - child->thread.debugreg[n] = data; - return 0; } diff --git a/arch/x86/kernel/signal_32.c b/arch/x86/kernel/signal_32.c index 64cb3c0..2bf5c9a 100644 --- a/arch/x86/kernel/signal_32.c +++ b/arch/x86/kernel/signal_32.c @@ -605,8 +605,8 @@ static void fastcall do_signal(struct pt_regs *regs) * have been cleared if the watchpoint triggered * inside the kernel. */ - if (unlikely(current->thread.debugreg[7])) - set_debugreg(current->thread.debugreg[7], 7); + if (unlikely(current->thread.debugreg7)) + set_debugreg(current->thread.debugreg7, 7); /* Whee! Actually deliver the signal. */ if (handle_signal(signr, &info, &ka, oldset, regs) == 0) { diff --git a/arch/x86/kernel/traps_32.c b/arch/x86/kernel/traps_32.c index 931ef10..2771355 100644 --- a/arch/x86/kernel/traps_32.c +++ b/arch/x86/kernel/traps_32.c @@ -852,7 +852,7 @@ fastcall void __kprobes do_debug(struct pt_regs * regs, long error_code) /* Mask out spurious debug traps due to lazy DR7 setting */ if (condition & (DR_TRAP0|DR_TRAP1|DR_TRAP2|DR_TRAP3)) { - if (!tsk->thread.debugreg[7]) + if (!tsk->thread.debugreg7) goto clear_dr7; } @@ -860,7 +860,7 @@ fastcall void __kprobes do_debug(struct pt_regs * regs, long error_code) goto debug_vm86; /* Save debug status register where ptrace can see it */ - tsk->thread.debugreg[6] = condition; + tsk->thread.debugreg6 = condition; /* * Single-stepping through TF: make sure we ignore any events in diff --git a/arch/x86/power/cpu.c b/arch/x86/power/cpu.c index 998fd3e..5a98dc3 100644 --- a/arch/x86/power/cpu.c +++ b/arch/x86/power/cpu.c @@ -74,14 +74,14 @@ static void fix_processor_context(void) /* * Now maybe reload the debug registers */ - if (current->thread.debugreg[7]){ - set_debugreg(current->thread.debugreg[0], 0); - set_debugreg(current->thread.debugreg[1], 1); - set_debugreg(current->thread.debugreg[2], 2); - set_debugreg(current->thread.debugreg[3], 3); + if (current->thread.debugreg7) { + set_debugreg(current->thread.debugreg0, 0); + set_debugreg(current->thread.debugreg1, 1); + set_debugreg(current->thread.debugreg2, 2); + set_debugreg(current->thread.debugreg3, 3); /* no 4 and 5 */ - set_debugreg(current->thread.debugreg[6], 6); - set_debugreg(current->thread.debugreg[7], 7); + set_debugreg(current->thread.debugreg6, 6); + set_debugreg(current->thread.debugreg7, 7); } } diff --git a/include/asm-x86/processor_32.h b/include/asm-x86/processor_32.h index c85400f..d50a4b4 100644 --- a/include/asm-x86/processor_32.h +++ b/include/asm-x86/processor_32.h @@ -353,7 +353,12 @@ struct thread_struct { unsigned long fs; unsigned long gs; /* Hardware debugging registers */ - unsigned long debugreg[8]; /* %%db0-7 debug registers */ + unsigned long debugreg0; + unsigned long debugreg1; + unsigned long debugreg2; + unsigned long debugreg3; + unsigned long debugreg6; + unsigned long debugreg7; /* fault info */ unsigned long cr2, trap_no, error_code; /* floating point info */ -- 2.7.4