Commit c6a2f467 authored by Atsushi Nemoto's avatar Atsushi Nemoto Committed by Ralf Baechle

[MIPS] Check FCSR for pending interrupts, alternative version

Commit 6d667106 is incomplete and misses
non-r4k CPUs.  This patch reverts the commit and fixes in other way.

 o Do FCSR checking in caller of restore_fp_context.
 o Send SIGFPE if the signal handler set any FPU exception bits.
Signed-off-by: default avatarAtsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: default avatarRalf Baechle <ralf@linux-mips.org>
parent f1dbf8e7
......@@ -114,14 +114,6 @@ LEAF(_save_fp_context32)
*/
LEAF(_restore_fp_context)
EX lw t0, SC_FPC_CSR(a0)
/* Fail if the CSR has exceptions pending */
srl t1, t0, 5
and t1, t0
andi t1, 0x1f << 7
bnez t1, fault
nop
#ifdef CONFIG_64BIT
EX ldc1 $f1, SC_FPREGS+8(a0)
EX ldc1 $f3, SC_FPREGS+24(a0)
......@@ -165,14 +157,6 @@ LEAF(_restore_fp_context)
LEAF(_restore_fp_context32)
/* Restore an o32 sigcontext. */
EX lw t0, SC32_FPC_CSR(a0)
/* Fail if the CSR has exceptions pending */
srl t1, t0, 5
and t1, t0
andi t1, 0x1f << 7
bnez t1, fault
nop
EX ldc1 $f0, SC32_FPREGS+0(a0)
EX ldc1 $f2, SC32_FPREGS+16(a0)
EX ldc1 $f4, SC32_FPREGS+32(a0)
......
......@@ -31,4 +31,7 @@ extern void __user *get_sigframe(struct k_sigaction *ka, struct pt_regs *regs,
*/
extern int install_sigtramp(unsigned int __user *tramp, unsigned int syscall);
/* Check and clear pending FPU exceptions in saved CSR */
extern int fpcsr_pending(unsigned int __user *fpcsr);
#endif /* __SIGNAL_COMMON_H */
......@@ -124,6 +124,37 @@ int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
return err;
}
int fpcsr_pending(unsigned int __user *fpcsr)
{
int err, sig = 0;
unsigned int csr, enabled;
err = __get_user(csr, fpcsr);
enabled = FPU_CSR_UNI_X | ((csr & FPU_CSR_ALL_E) << 5);
/*
* If the signal handler set some FPU exceptions, clear it and
* send SIGFPE.
*/
if (csr & enabled) {
csr &= ~enabled;
err |= __put_user(csr, fpcsr);
sig = SIGFPE;
}
return err ?: sig;
}
static int
check_and_restore_fp_context(struct sigcontext __user *sc)
{
int err, sig;
err = sig = fpcsr_pending(&sc->sc_fpc_csr);
if (err > 0)
err = 0;
err |= restore_fp_context(sc);
return err ?: sig;
}
int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
{
unsigned int used_math;
......@@ -162,7 +193,8 @@ int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
if (used_math()) {
/* restore fpu context if we have used it before */
own_fpu();
err |= restore_fp_context(sc);
if (!err)
err = check_and_restore_fp_context(sc);
} else {
/* signal handler may have used FPU. Give it up. */
lose_fpu();
......@@ -332,6 +364,7 @@ asmlinkage void sys_sigreturn(nabi_no_regargs struct pt_regs regs)
{
struct sigframe __user *frame;
sigset_t blocked;
int sig;
frame = (struct sigframe __user *) regs.regs[29];
if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
......@@ -345,8 +378,11 @@ asmlinkage void sys_sigreturn(nabi_no_regargs struct pt_regs regs)
recalc_sigpending();
spin_unlock_irq(&current->sighand->siglock);
if (restore_sigcontext(&regs, &frame->sf_sc))
sig = restore_sigcontext(&regs, &frame->sf_sc);
if (sig < 0)
goto badframe;
else if (sig)
force_sig(sig, current);
/*
* Don't let your children do this ...
......@@ -368,6 +404,7 @@ asmlinkage void sys_rt_sigreturn(nabi_no_regargs struct pt_regs regs)
struct rt_sigframe __user *frame;
sigset_t set;
stack_t st;
int sig;
frame = (struct rt_sigframe __user *) regs.regs[29];
if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
......@@ -381,8 +418,11 @@ asmlinkage void sys_rt_sigreturn(nabi_no_regargs struct pt_regs regs)
recalc_sigpending();
spin_unlock_irq(&current->sighand->siglock);
if (restore_sigcontext(&regs, &frame->rs_uc.uc_mcontext))
sig = restore_sigcontext(&regs, &frame->rs_uc.uc_mcontext);
if (sig < 0)
goto badframe;
else if (sig)
force_sig(sig, current);
if (__copy_from_user(&st, &frame->rs_uc.uc_stack, sizeof(st)))
goto badframe;
......
......@@ -220,6 +220,18 @@ static int setup_sigcontext32(struct pt_regs *regs,
return err;
}
static int
check_and_restore_fp_context32(struct sigcontext32 __user *sc)
{
int err, sig;
err = sig = fpcsr_pending(&sc->sc_fpc_csr);
if (err > 0)
err = 0;
err |= restore_fp_context32(sc);
return err ?: sig;
}
static int restore_sigcontext32(struct pt_regs *regs,
struct sigcontext32 __user *sc)
{
......@@ -255,7 +267,8 @@ static int restore_sigcontext32(struct pt_regs *regs,
if (used_math()) {
/* restore fpu context if we have used it before */
own_fpu();
err |= restore_fp_context32(sc);
if (!err)
err = check_and_restore_fp_context32(sc);
} else {
/* signal handler may have used FPU. Give it up. */
lose_fpu();
......@@ -508,6 +521,7 @@ asmlinkage void sys32_sigreturn(nabi_no_regargs struct pt_regs regs)
{
struct sigframe32 __user *frame;
sigset_t blocked;
int sig;
frame = (struct sigframe32 __user *) regs.regs[29];
if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
......@@ -521,8 +535,11 @@ asmlinkage void sys32_sigreturn(nabi_no_regargs struct pt_regs regs)
recalc_sigpending();
spin_unlock_irq(&current->sighand->siglock);
if (restore_sigcontext32(&regs, &frame->sf_sc))
sig = restore_sigcontext32(&regs, &frame->sf_sc);
if (sig < 0)
goto badframe;
else if (sig)
force_sig(sig, current);
/*
* Don't let your children do this ...
......@@ -545,6 +562,7 @@ asmlinkage void sys32_rt_sigreturn(nabi_no_regargs struct pt_regs regs)
sigset_t set;
stack_t st;
s32 sp;
int sig;
frame = (struct rt_sigframe32 __user *) regs.regs[29];
if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
......@@ -558,8 +576,11 @@ asmlinkage void sys32_rt_sigreturn(nabi_no_regargs struct pt_regs regs)
recalc_sigpending();
spin_unlock_irq(&current->sighand->siglock);
if (restore_sigcontext32(&regs, &frame->rs_uc.uc_mcontext))
sig = restore_sigcontext32(&regs, &frame->rs_uc.uc_mcontext);
if (sig < 0)
goto badframe;
else if (sig)
force_sig(sig, current);
/* The ucontext contains a stack32_t, so we must convert! */
if (__get_user(sp, &frame->rs_uc.uc_stack.ss_sp))
......
......@@ -127,6 +127,7 @@ asmlinkage void sysn32_rt_sigreturn(nabi_no_regargs struct pt_regs regs)
sigset_t set;
stack_t st;
s32 sp;
int sig;
frame = (struct rt_sigframe_n32 __user *) regs.regs[29];
if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
......@@ -140,8 +141,11 @@ asmlinkage void sysn32_rt_sigreturn(nabi_no_regargs struct pt_regs regs)
recalc_sigpending();
spin_unlock_irq(&current->sighand->siglock);
if (restore_sigcontext(&regs, &frame->rs_uc.uc_mcontext))
sig = restore_sigcontext(&regs, &frame->rs_uc.uc_mcontext);
if (sig < 0)
goto badframe;
else if (sig)
force_sig(sig, current);
/* The ucontext contains a stack32_t, so we must convert! */
if (__get_user(sp, &frame->rs_uc.uc_stack.ss_sp))
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment