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| author | Jeremy Fitzhardinge | 2006-12-07 02:14:02 +0100 |
|---|---|---|
| committer | Andi Kleen | 2006-12-07 02:14:02 +0100 |
| commit | 66e10a44d724f1464b5e8b5a3eae1e2cbbc2cca6 (patch) | |
| tree | 0d2a1a1d5edaf98506ef7cb271cad62f5644268e | |
| parent | [PATCH] i386: Use %gs as the PDA base-segment in the kernel (diff) | |
| download | kernel-qcow2-linux-66e10a44d724f1464b5e8b5a3eae1e2cbbc2cca6.tar.gz kernel-qcow2-linux-66e10a44d724f1464b5e8b5a3eae1e2cbbc2cca6.tar.xz kernel-qcow2-linux-66e10a44d724f1464b5e8b5a3eae1e2cbbc2cca6.zip | |
[PATCH] i386: Fix places where using %gs changes the usermode ABI
There are a few places where the change in struct pt_regs and the use of %gs
affect the userspace ABI. These are primarily debugging interfaces where
thread state can be inspected or extracted.
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Chuck Ebbert <76306.1226@compuserve.com>
Cc: Zachary Amsden <zach@vmware.com>
Cc: Jan Beulich <jbeulich@novell.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
| -rw-r--r-- | arch/i386/kernel/process.c | 6 | ||||
| -rw-r--r-- | arch/i386/kernel/ptrace.c | 18 | ||||
| -rw-r--r-- | include/asm-i386/elf.h | 2 | ||||
| -rw-r--r-- | include/asm-i386/unwind.h | 1 |
4 files changed, 11 insertions, 16 deletions
diff --git a/arch/i386/kernel/process.c b/arch/i386/kernel/process.c index 905364d42847..dc4272545179 100644 --- a/arch/i386/kernel/process.c +++ b/arch/i386/kernel/process.c @@ -315,8 +315,8 @@ void show_regs(struct pt_regs * regs) regs->eax,regs->ebx,regs->ecx,regs->edx); printk("ESI: %08lx EDI: %08lx EBP: %08lx", regs->esi, regs->edi, regs->ebp); - printk(" DS: %04x ES: %04x\n", - 0xffff & regs->xds,0xffff & regs->xes); + printk(" DS: %04x ES: %04x GS: %04x\n", + 0xffff & regs->xds,0xffff & regs->xes, 0xffff & regs->xgs); cr0 = read_cr0(); cr2 = read_cr2(); @@ -509,7 +509,7 @@ void dump_thread(struct pt_regs * regs, struct user * dump) dump->regs.ds = regs->xds; dump->regs.es = regs->xes; savesegment(fs,dump->regs.fs); - savesegment(gs,dump->regs.gs); + dump->regs.gs = regs->xgs; dump->regs.orig_eax = regs->orig_eax; dump->regs.eip = regs->eip; dump->regs.cs = regs->xcs; diff --git a/arch/i386/kernel/ptrace.c b/arch/i386/kernel/ptrace.c index 775f50e9395b..f3f94ac5736a 100644 --- a/arch/i386/kernel/ptrace.c +++ b/arch/i386/kernel/ptrace.c @@ -94,13 +94,9 @@ static int putreg(struct task_struct *child, return -EIO; child->thread.fs = value; return 0; - case GS: - if (value && (value & 3) != 3) - return -EIO; - child->thread.gs = value; - return 0; case DS: case ES: + case GS: if (value && (value & 3) != 3) return -EIO; value &= 0xffff; @@ -116,8 +112,8 @@ static int putreg(struct task_struct *child, value |= get_stack_long(child, EFL_OFFSET) & ~FLAG_MASK; break; } - if (regno > GS*4) - regno -= 2*4; + if (regno > ES*4) + regno -= 1*4; put_stack_long(child, regno - sizeof(struct pt_regs), value); return 0; } @@ -131,18 +127,16 @@ static unsigned long getreg(struct task_struct *child, case FS: retval = child->thread.fs; break; - case GS: - retval = child->thread.gs; - break; case DS: case ES: + case GS: case SS: case CS: retval = 0xffff; /* fall through */ default: - if (regno > GS*4) - regno -= 2*4; + if (regno > ES*4) + regno -= 1*4; regno = regno - sizeof(struct pt_regs); retval &= get_stack_long(child, regno); } diff --git a/include/asm-i386/elf.h b/include/asm-i386/elf.h index 3a05436f31c0..45d21a0c95bf 100644 --- a/include/asm-i386/elf.h +++ b/include/asm-i386/elf.h @@ -91,7 +91,7 @@ typedef struct user_fxsr_struct elf_fpxregset_t; pr_reg[7] = regs->xds; \ pr_reg[8] = regs->xes; \ savesegment(fs,pr_reg[9]); \ - savesegment(gs,pr_reg[10]); \ + pr_reg[10] = regs->xgs; \ pr_reg[11] = regs->orig_eax; \ pr_reg[12] = regs->eip; \ pr_reg[13] = regs->xcs; \ diff --git a/include/asm-i386/unwind.h b/include/asm-i386/unwind.h index 5031d693b89d..601fc67bd775 100644 --- a/include/asm-i386/unwind.h +++ b/include/asm-i386/unwind.h @@ -71,6 +71,7 @@ static inline void arch_unw_init_blocked(struct unwind_frame_info *info) info->regs.xss = __KERNEL_DS; info->regs.xds = __USER_DS; info->regs.xes = __USER_DS; + info->regs.xgs = __KERNEL_PDA; } extern asmlinkage int arch_unwind_init_running(struct unwind_frame_info *, |