From 4e63f8edfe4d6f20b1af176efc022c2b2f5e7aeb Mon Sep 17 00:00:00 2001 From: Benjamin Herrenschmidt Date: Sun, 9 Jun 2013 17:01:24 +1000 Subject: powerpc/math-emu: Allow math-emu to be used for HW FPU (Including 64-bit ones) This allow SW emulation by the kernel of optional instructions such as fsqrt which aren't implemented on some processors, and thus fixes some Fedora 19 issues such as Anaconda since the compiler is set to generate those by default on 64-bit. Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/kernel/traps.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) (limited to 'arch/powerpc/kernel/traps.c') diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c index f18c79c324ef..f4b5687b0c66 100644 --- a/arch/powerpc/kernel/traps.c +++ b/arch/powerpc/kernel/traps.c @@ -1125,7 +1125,17 @@ void __kprobes program_check_exception(struct pt_regs *regs) * ESR_DST (!?) or 0. In the process of chasing this with the * hardware people - not sure if it can happen on any illegal * instruction or only on FP instructions, whether there is a - * pattern to occurrences etc. -dgibson 31/Mar/2003 */ + * pattern to occurrences etc. -dgibson 31/Mar/2003 + */ + + /* + * If we support a HW FPU, we need to ensure the FP state + * if flushed into the thread_struct before attempting + * emulation + */ +#ifdef CONFIG_PPC_FPU + flush_fp_to_thread(current); +#endif switch (do_mathemu(regs)) { case 0: emulate_single_step(regs); -- cgit v1.2.1 From 968219fa334ce8fed3421dd12ea12e9f562c95cb Mon Sep 17 00:00:00 2001 From: Benjamin Herrenschmidt Date: Sun, 9 Jun 2013 17:04:58 +1000 Subject: powerpc/8xx: Remove 8xx specific "minimal FPU emulation" This is duplicated code from math-emu and implements such a small subset of the FPU (load/stores/fmr) that it's essentially pointless nowdays. Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/kernel/traps.c | 22 +--------------------- 1 file changed, 1 insertion(+), 21 deletions(-) (limited to 'arch/powerpc/kernel/traps.c') diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c index f4b5687b0c66..071f6e040eb2 100644 --- a/arch/powerpc/kernel/traps.c +++ b/arch/powerpc/kernel/traps.c @@ -1396,8 +1396,7 @@ void performance_monitor_exception(struct pt_regs *regs) void SoftwareEmulation(struct pt_regs *regs) { extern int do_mathemu(struct pt_regs *); - extern int Soft_emulate_8xx(struct pt_regs *); -#if defined(CONFIG_MATH_EMULATION) || defined(CONFIG_8XX_MINIMAL_FPEMU) +#if defined(CONFIG_MATH_EMULATION) int errcode; #endif @@ -1430,23 +1429,6 @@ void SoftwareEmulation(struct pt_regs *regs) _exception(SIGILL, regs, ILL_ILLOPC, regs->nip); return; } - -#elif defined(CONFIG_8XX_MINIMAL_FPEMU) - errcode = Soft_emulate_8xx(regs); - if (errcode >= 0) - PPC_WARN_EMULATED(8xx, regs); - - switch (errcode) { - case 0: - emulate_single_step(regs); - return; - case 1: - _exception(SIGILL, regs, ILL_ILLOPC, regs->nip); - return; - case -EFAULT: - _exception(SIGSEGV, regs, SEGV_MAPERR, regs->nip); - return; - } #else _exception(SIGILL, regs, ILL_ILLOPC, regs->nip); #endif @@ -1796,8 +1778,6 @@ struct ppc_emulated ppc_emulated = { WARN_EMULATED_SETUP(unaligned), #ifdef CONFIG_MATH_EMULATION WARN_EMULATED_SETUP(math), -#elif defined(CONFIG_8XX_MINIMAL_FPEMU) - WARN_EMULATED_SETUP(8xx), #endif #ifdef CONFIG_VSX WARN_EMULATED_SETUP(vsx), -- cgit v1.2.1 From 80aa0fb4940bf8ee52bcb574d74459a7aea45621 Mon Sep 17 00:00:00 2001 From: James Yang Date: Tue, 25 Jun 2013 11:41:05 -0500 Subject: powerpc: Fix string instr. emulation for 32-bit processes on ppc64 String instruction emulation would erroneously result in a segfault if the upper bits of the EA are set and is so high that it fails access check. Truncate the EA to 32 bits if the process is 32-bit. Signed-off-by: James Yang Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/kernel/traps.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'arch/powerpc/kernel/traps.c') diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c index 071f6e040eb2..300daf3e7ab0 100644 --- a/arch/powerpc/kernel/traps.c +++ b/arch/powerpc/kernel/traps.c @@ -866,6 +866,10 @@ static int emulate_string_inst(struct pt_regs *regs, u32 instword) u8 val; u32 shift = 8 * (3 - (pos & 0x3)); + /* if process is 32-bit, clear upper 32 bits of EA */ + if ((regs->msr & MSR_64BIT) == 0) + EA &= 0xFFFFFFFF; + switch ((instword & PPC_INST_STRING_MASK)) { case PPC_INST_LSWX: case PPC_INST_LSWI: -- cgit v1.2.1 From 021424a1fce335e05807fd770eb8e1da30a63eea Mon Sep 17 00:00:00 2001 From: Michael Ellerman Date: Tue, 25 Jun 2013 17:47:56 +1000 Subject: powerpc: Rename and flesh out the facility unavailable exception handler The exception at 0xf60 is not the TM (Transactional Memory) unavailable exception, it is the "Facility Unavailable Exception", rename it as such. Flesh out the handler to acknowledge the fact that it can be called for many reasons, one of which is TM being unavailable. Use STD_EXCEPTION_COMMON() for the exception body, for some reason we had it open-coded, I've checked the generated code is identical. Signed-off-by: Michael Ellerman CC: [v3.10] Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/kernel/traps.c | 33 +++++++++++++++++++++++++-------- 1 file changed, 25 insertions(+), 8 deletions(-) (limited to 'arch/powerpc/kernel/traps.c') diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c index 300daf3e7ab0..11f448812dc1 100644 --- a/arch/powerpc/kernel/traps.c +++ b/arch/powerpc/kernel/traps.c @@ -1286,25 +1286,42 @@ void vsx_unavailable_exception(struct pt_regs *regs) die("Unrecoverable VSX Unavailable Exception", regs, SIGABRT); } -void tm_unavailable_exception(struct pt_regs *regs) +void facility_unavailable_exception(struct pt_regs *regs) { + static char *facility_strings[] = { + "FPU", + "VMX/VSX", + "DSCR", + "PMU SPRs", + "BHRB", + "TM", + "AT", + "EBB", + "TAR", + }; + char *facility; + u64 value; + + value = mfspr(SPRN_FSCR) >> 56; + /* We restore the interrupt state now */ if (!arch_irq_disabled_regs(regs)) local_irq_enable(); - /* Currently we never expect a TMU exception. Catch - * this and kill the process! - */ - printk(KERN_EMERG "Unexpected TM unavailable exception at %lx " - "(msr %lx)\n", - regs->nip, regs->msr); + if (value < ARRAY_SIZE(facility_strings)) + facility = facility_strings[value]; + else + facility = "unknown"; + + pr_err("Facility '%s' unavailable, exception at 0x%lx, MSR=%lx\n", + facility, regs->nip, regs->msr); if (user_mode(regs)) { _exception(SIGILL, regs, ILL_ILLOPC, regs->nip); return; } - die("Unexpected TM unavailable exception", regs, SIGABRT); + die("Unexpected facility unavailable exception", regs, SIGABRT); } #ifdef CONFIG_PPC_TRANSACTIONAL_MEM -- cgit v1.2.1 From b14b6260efeee6eb8942c6e6420e31281892acb6 Mon Sep 17 00:00:00 2001 From: Michael Ellerman Date: Tue, 25 Jun 2013 17:47:57 +1000 Subject: powerpc: Wire up the HV facility unavailable exception Similar to the facility unavailble exception, except the facilities are controlled by HFSCR. Adapt the facility_unavailable_exception() so it can be called for either the regular or Hypervisor facility unavailable exceptions. Signed-off-by: Michael Ellerman CC: [v3.10] Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/kernel/traps.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-) (limited to 'arch/powerpc/kernel/traps.c') diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c index 11f448812dc1..4a87fcbe3ba9 100644 --- a/arch/powerpc/kernel/traps.c +++ b/arch/powerpc/kernel/traps.c @@ -1299,10 +1299,18 @@ void facility_unavailable_exception(struct pt_regs *regs) "EBB", "TAR", }; - char *facility; + char *facility, *prefix; u64 value; - value = mfspr(SPRN_FSCR) >> 56; + if (regs->trap == 0xf60) { + value = mfspr(SPRN_FSCR); + prefix = ""; + } else { + value = mfspr(SPRN_HFSCR); + prefix = "Hypervisor "; + } + + value = value >> 56; /* We restore the interrupt state now */ if (!arch_irq_disabled_regs(regs)) @@ -1313,8 +1321,8 @@ void facility_unavailable_exception(struct pt_regs *regs) else facility = "unknown"; - pr_err("Facility '%s' unavailable, exception at 0x%lx, MSR=%lx\n", - facility, regs->nip, regs->msr); + pr_err("%sFacility '%s' unavailable, exception at 0x%lx, MSR=%lx\n", + prefix, facility, regs->nip, regs->msr); if (user_mode(regs)) { _exception(SIGILL, regs, ILL_ILLOPC, regs->nip); -- cgit v1.2.1