diff options
Diffstat (limited to 'debian/patches-rt/0004-ARM-vfp-Move-sending-signals-outside-of-vfp_lock-ed-.patch')
| -rw-r--r-- | debian/patches-rt/0004-ARM-vfp-Move-sending-signals-outside-of-vfp_lock-ed-.patch | 121 |
1 files changed, 121 insertions, 0 deletions
diff --git a/debian/patches-rt/0004-ARM-vfp-Move-sending-signals-outside-of-vfp_lock-ed-.patch b/debian/patches-rt/0004-ARM-vfp-Move-sending-signals-outside-of-vfp_lock-ed-.patch new file mode 100644 index 0000000000..f7e006261e --- /dev/null +++ b/debian/patches-rt/0004-ARM-vfp-Move-sending-signals-outside-of-vfp_lock-ed-.patch @@ -0,0 +1,121 @@ +From: Sebastian Andrzej Siewior <bigeasy@linutronix.de> +Date: Wed, 28 Jun 2023 09:39:33 +0200 +Subject: [PATCH 4/4] ARM: vfp: Move sending signals outside of vfp_lock()ed + section. +Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/6.6/older/patches-6.6.7-rt18.tar.xz + +VFP_bounce() is invoked from within vfp_support_entry() and may send a +signal. Sending a signal uses spinlock_t which becomes a sleeping lock +on PREEMPT_RT and must not be acquired within a preempt-disabled +section. + +Move the vfp_raise_sigfpe() block outside of the vfp_lock() section. + +Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> +--- + arch/arm/vfp/vfpmodule.c | 29 ++++++++++++++++++----------- + 1 file changed, 18 insertions(+), 11 deletions(-) + +--- a/arch/arm/vfp/vfpmodule.c ++++ b/arch/arm/vfp/vfpmodule.c +@@ -268,7 +268,7 @@ static void vfp_panic(char *reason, u32 + /* + * Process bitmask of exception conditions. + */ +-static void vfp_raise_exceptions(u32 exceptions, u32 inst, u32 fpscr, struct pt_regs *regs) ++static int vfp_raise_exceptions(u32 exceptions, u32 inst, u32 fpscr) + { + int si_code = 0; + +@@ -276,8 +276,7 @@ static void vfp_raise_exceptions(u32 exc + + if (exceptions == VFP_EXCEPTION_ERROR) { + vfp_panic("unhandled bounce", inst); +- vfp_raise_sigfpe(FPE_FLTINV, regs); +- return; ++ return FPE_FLTINV; + } + + /* +@@ -305,8 +304,7 @@ static void vfp_raise_exceptions(u32 exc + RAISE(FPSCR_OFC, FPSCR_OFE, FPE_FLTOVF); + RAISE(FPSCR_IOC, FPSCR_IOE, FPE_FLTINV); + +- if (si_code) +- vfp_raise_sigfpe(si_code, regs); ++ return si_code; + } + + /* +@@ -352,6 +350,8 @@ static u32 vfp_emulate_instruction(u32 i + static void VFP_bounce(u32 trigger, u32 fpexc, struct pt_regs *regs) + { + u32 fpscr, orig_fpscr, fpsid, exceptions; ++ int si_code2 = 0; ++ int si_code = 0; + + pr_debug("VFP: bounce: trigger %08x fpexc %08x\n", trigger, fpexc); + +@@ -397,8 +397,8 @@ static void VFP_bounce(u32 trigger, u32 + * unallocated VFP instruction but with FPSCR.IXE set and not + * on VFP subarch 1. + */ +- vfp_raise_exceptions(VFP_EXCEPTION_ERROR, trigger, fpscr, regs); +- return; ++ si_code = vfp_raise_exceptions(VFP_EXCEPTION_ERROR, trigger, fpscr); ++ goto exit; + } + + /* +@@ -422,14 +422,14 @@ static void VFP_bounce(u32 trigger, u32 + */ + exceptions = vfp_emulate_instruction(trigger, fpscr, regs); + if (exceptions) +- vfp_raise_exceptions(exceptions, trigger, orig_fpscr, regs); ++ si_code2 = vfp_raise_exceptions(exceptions, trigger, orig_fpscr); + + /* + * If there isn't a second FP instruction, exit now. Note that + * the FPEXC.FP2V bit is valid only if FPEXC.EX is 1. + */ + if ((fpexc & (FPEXC_EX | FPEXC_FP2V)) != (FPEXC_EX | FPEXC_FP2V)) +- return; ++ goto exit; + + /* + * The barrier() here prevents fpinst2 being read +@@ -441,7 +441,13 @@ static void VFP_bounce(u32 trigger, u32 + emulate: + exceptions = vfp_emulate_instruction(trigger, orig_fpscr, regs); + if (exceptions) +- vfp_raise_exceptions(exceptions, trigger, orig_fpscr, regs); ++ si_code = vfp_raise_exceptions(exceptions, trigger, orig_fpscr); ++exit: ++ vfp_unlock(); ++ if (si_code2) ++ vfp_raise_sigfpe(si_code2, regs); ++ if (si_code) ++ vfp_raise_sigfpe(si_code, regs); + } + + static void vfp_enable(void *unused) +@@ -773,6 +779,7 @@ static int vfp_support_entry(struct pt_r + * replay the instruction that trapped. + */ + fmxr(FPEXC, fpexc); ++ vfp_unlock(); + } else { + /* Check for synchronous or asynchronous exceptions */ + if (!(fpexc & (FPEXC_EX | FPEXC_DEX))) { +@@ -794,10 +801,10 @@ static int vfp_support_entry(struct pt_r + } + } + bounce: regs->ARM_pc += 4; ++ /* VFP_bounce() will invoke vfp_unlock() */ + VFP_bounce(trigger, fpexc, regs); + } + +- vfp_unlock(); + return 0; + } + |