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Diffstat (limited to 'arch/x86/kernel/signal.c')
-rw-r--r--arch/x86/kernel/signal.c64
1 files changed, 39 insertions, 25 deletions
diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c
index 1ea14fd53933..71820c42b6ce 100644
--- a/arch/x86/kernel/signal.c
+++ b/arch/x86/kernel/signal.c
@@ -26,8 +26,8 @@
#include <asm/processor.h>
#include <asm/ucontext.h>
-#include <asm/i387.h>
-#include <asm/fpu-internal.h>
+#include <asm/fpu/internal.h>
+#include <asm/fpu/signal.h>
#include <asm/vdso.h>
#include <asm/mce.h>
#include <asm/sighandling.h>
@@ -93,8 +93,15 @@ int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
COPY(r15);
#endif /* CONFIG_X86_64 */
+#ifdef CONFIG_X86_32
COPY_SEG_CPL3(cs);
COPY_SEG_CPL3(ss);
+#else /* !CONFIG_X86_32 */
+ /* Kernel saves and restores only the CS segment register on signals,
+ * which is the bare minimum needed to allow mixed 32/64-bit code.
+ * App's signal handler can save/restore other segments if needed. */
+ COPY_SEG_CPL3(cs);
+#endif /* CONFIG_X86_32 */
get_user_ex(tmpflags, &sc->flags);
regs->flags = (regs->flags & ~FIX_EFLAGS) | (tmpflags & FIX_EFLAGS);
@@ -103,7 +110,7 @@ int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
get_user_ex(buf, &sc->fpstate);
} get_user_catch(err);
- err |= restore_xstate_sig(buf, config_enabled(CONFIG_X86_32));
+ err |= fpu__restore_sig(buf, config_enabled(CONFIG_X86_32));
force_iret();
@@ -154,9 +161,8 @@ int setup_sigcontext(struct sigcontext __user *sc, void __user *fpstate,
#else /* !CONFIG_X86_32 */
put_user_ex(regs->flags, &sc->flags);
put_user_ex(regs->cs, &sc->cs);
- put_user_ex(0, &sc->__pad2);
- put_user_ex(0, &sc->__pad1);
- put_user_ex(regs->ss, &sc->ss);
+ put_user_ex(0, &sc->gs);
+ put_user_ex(0, &sc->fs);
#endif /* CONFIG_X86_32 */
put_user_ex(fpstate, &sc->fpstate);
@@ -199,6 +205,7 @@ get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size,
unsigned long sp = regs->sp;
unsigned long buf_fx = 0;
int onsigstack = on_sig_stack(sp);
+ struct fpu *fpu = &current->thread.fpu;
/* redzone */
if (config_enabled(CONFIG_X86_64))
@@ -218,9 +225,9 @@ get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size,
}
}
- if (used_math()) {
- sp = alloc_mathframe(sp, config_enabled(CONFIG_X86_32),
- &buf_fx, &math_size);
+ if (fpu->fpstate_active) {
+ sp = fpu__alloc_mathframe(sp, config_enabled(CONFIG_X86_32),
+ &buf_fx, &math_size);
*fpstate = (void __user *)sp;
}
@@ -234,8 +241,8 @@ get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size,
return (void __user *)-1L;
/* save i387 and extended state */
- if (used_math() &&
- save_xstate_sig(*fpstate, (void __user *)buf_fx, math_size) < 0)
+ if (fpu->fpstate_active &&
+ copy_fpstate_to_sigframe(*fpstate, (void __user *)buf_fx, math_size) < 0)
return (void __user *)-1L;
return (void __user *)sp;
@@ -450,19 +457,9 @@ static int __setup_rt_frame(int sig, struct ksignal *ksig,
regs->sp = (unsigned long)frame;
- /*
- * Set up the CS and SS registers to run signal handlers in
- * 64-bit mode, even if the handler happens to be interrupting
- * 32-bit or 16-bit code.
- *
- * SS is subtle. In 64-bit mode, we don't need any particular
- * SS descriptor, but we do need SS to be valid. It's possible
- * that the old SS is entirely bogus -- this can happen if the
- * signal we're trying to deliver is #GP or #SS caused by a bad
- * SS value.
- */
+ /* Set up the CS register to run signal handlers in 64-bit mode,
+ even if the handler happens to be interrupting 32-bit code. */
regs->cs = __USER_CS;
- regs->ss = __USER_DS;
return 0;
}
@@ -593,6 +590,22 @@ badframe:
return 0;
}
+static inline int is_ia32_compat_frame(void)
+{
+ return config_enabled(CONFIG_IA32_EMULATION) &&
+ test_thread_flag(TIF_IA32);
+}
+
+static inline int is_ia32_frame(void)
+{
+ return config_enabled(CONFIG_X86_32) || is_ia32_compat_frame();
+}
+
+static inline int is_x32_frame(void)
+{
+ return config_enabled(CONFIG_X86_X32_ABI) && test_thread_flag(TIF_X32);
+}
+
static int
setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs)
{
@@ -617,6 +630,7 @@ static void
handle_signal(struct ksignal *ksig, struct pt_regs *regs)
{
bool stepping, failed;
+ struct fpu *fpu = &current->thread.fpu;
/* Are we from a system call? */
if (syscall_get_nr(current, regs) >= 0) {
@@ -665,8 +679,8 @@ handle_signal(struct ksignal *ksig, struct pt_regs *regs)
/*
* Ensure the signal handler starts with the new fpu state.
*/
- if (used_math())
- fpu_reset_state(current);
+ if (fpu->fpstate_active)
+ fpu__clear(fpu);
}
signal_setup_done(failed, ksig, stepping);
}