x86/asm/32: Remove a bunch of '& 0xffff' from pt_regs segment reads

Now that pt_regs properly defines segment fields as 16-bit on 32-bit
CPUs, there's no need to mask off the high word.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Andy Lutomirski 2017-07-28 06:00:32 -07:00 committed by Ingo Molnar
parent 630c1863bc
commit 99504819fc
8 changed files with 12 additions and 13 deletions

View File

@ -226,7 +226,7 @@ static void __user *get_sigframe(struct ksignal *ksig, struct pt_regs *regs,
if (ksig->ka.sa.sa_flags & SA_ONSTACK) if (ksig->ka.sa.sa_flags & SA_ONSTACK)
sp = sigsp(sp, ksig); sp = sigsp(sp, ksig);
/* This is the legacy signal stack switching. */ /* This is the legacy signal stack switching. */
else if ((regs->ss & 0xffff) != __USER32_DS && else if (regs->ss != __USER32_DS &&
!(ksig->ka.sa.sa_flags & SA_RESTORER) && !(ksig->ka.sa.sa_flags & SA_RESTORER) &&
ksig->ka.sa.sa_restorer) ksig->ka.sa.sa_restorer)
sp = (unsigned long) ksig->ka.sa.sa_restorer; sp = (unsigned long) ksig->ka.sa.sa_restorer;

View File

@ -126,15 +126,15 @@ do { \
pr_reg[4] = regs->di; \ pr_reg[4] = regs->di; \
pr_reg[5] = regs->bp; \ pr_reg[5] = regs->bp; \
pr_reg[6] = regs->ax; \ pr_reg[6] = regs->ax; \
pr_reg[7] = regs->ds & 0xffff; \ pr_reg[7] = regs->ds; \
pr_reg[8] = regs->es & 0xffff; \ pr_reg[8] = regs->es; \
pr_reg[9] = regs->fs & 0xffff; \ pr_reg[9] = regs->fs; \
pr_reg[11] = regs->orig_ax; \ pr_reg[11] = regs->orig_ax; \
pr_reg[12] = regs->ip; \ pr_reg[12] = regs->ip; \
pr_reg[13] = regs->cs & 0xffff; \ pr_reg[13] = regs->cs; \
pr_reg[14] = regs->flags; \ pr_reg[14] = regs->flags; \
pr_reg[15] = regs->sp; \ pr_reg[15] = regs->sp; \
pr_reg[16] = regs->ss & 0xffff; \ pr_reg[16] = regs->ss; \
} while (0); } while (0);
#define ELF_CORE_COPY_REGS(pr_reg, regs) \ #define ELF_CORE_COPY_REGS(pr_reg, regs) \

View File

@ -267,7 +267,7 @@ int __die(const char *str, struct pt_regs *regs, long err)
#ifdef CONFIG_X86_32 #ifdef CONFIG_X86_32
if (user_mode(regs)) { if (user_mode(regs)) {
sp = regs->sp; sp = regs->sp;
ss = regs->ss & 0xffff; ss = regs->ss;
} else { } else {
sp = kernel_stack_pointer(regs); sp = kernel_stack_pointer(regs);
savesegment(ss, ss); savesegment(ss, ss);

View File

@ -68,7 +68,7 @@ void __show_regs(struct pt_regs *regs, int all)
if (user_mode(regs)) { if (user_mode(regs)) {
sp = regs->sp; sp = regs->sp;
ss = regs->ss & 0xffff; ss = regs->ss;
gs = get_user_gs(regs); gs = get_user_gs(regs);
} else { } else {
sp = kernel_stack_pointer(regs); sp = kernel_stack_pointer(regs);

View File

@ -69,8 +69,7 @@ void __show_regs(struct pt_regs *regs, int all)
unsigned int fsindex, gsindex; unsigned int fsindex, gsindex;
unsigned int ds, cs, es; unsigned int ds, cs, es;
printk(KERN_DEFAULT "RIP: %04lx:%pS\n", regs->cs & 0xffff, printk(KERN_DEFAULT "RIP: %04lx:%pS\n", regs->cs, (void *)regs->ip);
(void *)regs->ip);
printk(KERN_DEFAULT "RSP: %04lx:%016lx EFLAGS: %08lx", regs->ss, printk(KERN_DEFAULT "RSP: %04lx:%016lx EFLAGS: %08lx", regs->ss,
regs->sp, regs->flags); regs->sp, regs->flags);
if (regs->orig_ax != -1) if (regs->orig_ax != -1)

View File

@ -256,7 +256,7 @@ get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size,
sp = current->sas_ss_sp + current->sas_ss_size; sp = current->sas_ss_sp + current->sas_ss_size;
} else if (IS_ENABLED(CONFIG_X86_32) && } else if (IS_ENABLED(CONFIG_X86_32) &&
!onsigstack && !onsigstack &&
(regs->ss & 0xffff) != __USER_DS && regs->ss != __USER_DS &&
!(ka->sa.sa_flags & SA_RESTORER) && !(ka->sa.sa_flags & SA_RESTORER) &&
ka->sa.sa_restorer) { ka->sa.sa_restorer) {
/* This is the legacy signal stack switching. */ /* This is the legacy signal stack switching. */

View File

@ -13,7 +13,7 @@ unsigned long convert_ip_to_linear(struct task_struct *child, struct pt_regs *re
unsigned long addr, seg; unsigned long addr, seg;
addr = regs->ip; addr = regs->ip;
seg = regs->cs & 0xffff; seg = regs->cs;
if (v8086_mode(regs)) { if (v8086_mode(regs)) {
addr = (addr & 0xffff) + (seg << 4); addr = (addr & 0xffff) + (seg << 4);
return addr; return addr;

View File

@ -142,7 +142,7 @@ void __init early_fixup_exception(struct pt_regs *regs, int trapnr)
* undefined. I'm not sure which CPUs do this, but at least * undefined. I'm not sure which CPUs do this, but at least
* the 486 DX works this way. * the 486 DX works this way.
*/ */
if ((regs->cs & 0xFFFF) != __KERNEL_CS) if (regs->cs != __KERNEL_CS)
goto fail; goto fail;
/* /*