From 4e90a2a7375e86827541bda9393414c03e7721c6 Mon Sep 17 00:00:00 2001 From: Anton Blanchard Date: Wed, 31 Jul 2013 16:31:26 +1000 Subject: powerpc: On POWERNV enable PPC_DENORMALISATION by default We want PPC_DENORMALISATION enabled when POWERNV is enabled, so update the Kconfig. Signed-off-by: Anton Blanchard Acked-by: Michael Neuling Signed-off-by: Benjamin Herrenschmidt CC: diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 3bf72cd..dbd9d3c 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -566,7 +566,7 @@ config SCHED_SMT config PPC_DENORMALISATION bool "PowerPC denormalisation exception handling" depends on PPC_BOOK3S_64 - default "n" + default "y" if PPC_POWERNV ---help--- Add support for handling denormalisation of single precision values. Useful for bare metal only. If unsure say Y here. -- cgit v0.10.2 From 7e76f34fa103677a27d96a7cfef8ce61389a32de Mon Sep 17 00:00:00 2001 From: Aruna Balakrishnaiah Date: Thu, 8 Aug 2013 22:33:49 +0530 Subject: powerpc/pseries: Fix buffer overflow when reading from pstore When reading from pstore there is a buffer overflow during decompression due to the header added in unzip_oops. Remove unzip_oops and call pstore_decompress directly in nvram_pstore_read. Allocate buffer of size report_length of the oops header as header will not be deallocated in pstore. Since we have 'openssl' command line tool to decompress the compressed data, dump the compressed data in case decompression fails instead of not dumping anything. Signed-off-by: Aruna Balakrishnaiah Signed-off-by: Benjamin Herrenschmidt diff --git a/arch/powerpc/platforms/pseries/nvram.c b/arch/powerpc/platforms/pseries/nvram.c index 9f8671a..893f360 100644 --- a/arch/powerpc/platforms/pseries/nvram.c +++ b/arch/powerpc/platforms/pseries/nvram.c @@ -569,35 +569,6 @@ error: return ret; } -static int unzip_oops(char *oops_buf, char *big_buf) -{ - struct oops_log_info *oops_hdr = (struct oops_log_info *)oops_buf; - u64 timestamp = oops_hdr->timestamp; - char *big_oops_data = NULL; - char *oops_data_buf = NULL; - size_t big_oops_data_sz; - int unzipped_len; - - big_oops_data = big_buf + sizeof(struct oops_log_info); - big_oops_data_sz = big_oops_buf_sz - sizeof(struct oops_log_info); - oops_data_buf = oops_buf + sizeof(struct oops_log_info); - - unzipped_len = nvram_decompress(oops_data_buf, big_oops_data, - oops_hdr->report_length, - big_oops_data_sz); - - if (unzipped_len < 0) { - pr_err("nvram: decompression failed; returned %d\n", - unzipped_len); - return -1; - } - oops_hdr = (struct oops_log_info *)big_buf; - oops_hdr->version = OOPS_HDR_VERSION; - oops_hdr->report_length = (u16) unzipped_len; - oops_hdr->timestamp = timestamp; - return 0; -} - static int nvram_pstore_open(struct pstore_info *psi) { /* Reset the iterator to start reading partitions again */ @@ -685,10 +656,9 @@ static ssize_t nvram_pstore_read(u64 *id, enum pstore_type_id *type, unsigned int err_type, id_no, size = 0; struct nvram_os_partition *part = NULL; char *buff = NULL, *big_buff = NULL; - int rc, sig = 0; + int sig = 0; loff_t p; -read_partition: read_type++; switch (nvram_type_ids[read_type]) { @@ -749,30 +719,36 @@ read_partition: *id = id_no; if (nvram_type_ids[read_type] == PSTORE_TYPE_DMESG) { + int length, unzipped_len; + oops_hdr = (struct oops_log_info *)buff; - *buf = buff + sizeof(*oops_hdr); + length = oops_hdr->report_length; + *buf = kmalloc(length, GFP_KERNEL); + if (*buf == NULL) + return -ENOMEM; + memcpy(*buf, buff + sizeof(*oops_hdr), length); + time->tv_sec = oops_hdr->timestamp; + time->tv_nsec = 0; + kfree(buff); if (err_type == ERR_TYPE_KERNEL_PANIC_GZ) { big_buff = kmalloc(big_oops_buf_sz, GFP_KERNEL); if (!big_buff) return -ENOMEM; - rc = unzip_oops(buff, big_buff); + unzipped_len = nvram_decompress(*buf, big_buff, + length, big_oops_buf_sz); - if (rc != 0) { - kfree(buff); + if (unzipped_len < 0) { + pr_err("nvram: decompression failed, returned " + "rc %d\n", unzipped_len); kfree(big_buff); - goto read_partition; + } else { + *buf = big_buff; + length = unzipped_len; } - - oops_hdr = (struct oops_log_info *)big_buff; - *buf = big_buff + sizeof(*oops_hdr); - kfree(buff); } - - time->tv_sec = oops_hdr->timestamp; - time->tv_nsec = 0; - return oops_hdr->report_length; + return length; } *buf = buff; @@ -816,6 +792,7 @@ static int nvram_pstore_init(void) static void __init nvram_init_oops_partition(int rtas_partition_exists) { int rc; + size_t size; rc = pseries_nvram_init_os_partition(&oops_log_partition); if (rc != 0) { @@ -844,8 +821,9 @@ static void __init nvram_init_oops_partition(int rtas_partition_exists) big_oops_buf_sz = (oops_data_sz * 100) / 45; big_oops_buf = kmalloc(big_oops_buf_sz, GFP_KERNEL); if (big_oops_buf) { - stream.workspace = kmalloc(zlib_deflate_workspacesize( - WINDOW_BITS, MEM_LEVEL), GFP_KERNEL); + size = max(zlib_deflate_workspacesize(WINDOW_BITS, MEM_LEVEL), + zlib_inflate_workspacesize()); + stream.workspace = kmalloc(size, GFP_KERNEL); if (!stream.workspace) { pr_err("nvram: No memory for compression workspace; " "skipping compression of %s partition data\n", -- cgit v0.10.2 From 156c9ebdaca20d9ce428dc189f2b24d2a0ec8eaf Mon Sep 17 00:00:00 2001 From: Aruna Balakrishnaiah Date: Thu, 8 Aug 2013 22:34:00 +0530 Subject: powerpc/pseries: Add backward compatibilty to read old kernel oops-log Older kernels has just length information in their header. Handle it while reading old kernel oops log from pstore. Applies on top of powerpc/pseries: Fix buffer overflow when reading from pstore Signed-off-by: Aruna Balakrishnaiah Signed-off-by: Benjamin Herrenschmidt diff --git a/arch/powerpc/platforms/pseries/nvram.c b/arch/powerpc/platforms/pseries/nvram.c index 893f360..6a5f2b1 100644 --- a/arch/powerpc/platforms/pseries/nvram.c +++ b/arch/powerpc/platforms/pseries/nvram.c @@ -720,15 +720,25 @@ static ssize_t nvram_pstore_read(u64 *id, enum pstore_type_id *type, if (nvram_type_ids[read_type] == PSTORE_TYPE_DMESG) { int length, unzipped_len; + size_t hdr_size; oops_hdr = (struct oops_log_info *)buff; - length = oops_hdr->report_length; + if (oops_hdr->version < OOPS_HDR_VERSION) { + /* Old format oops header had 2-byte record size */ + hdr_size = sizeof(u16); + length = oops_hdr->version; + time->tv_sec = 0; + time->tv_nsec = 0; + } else { + hdr_size = sizeof(*oops_hdr); + length = oops_hdr->report_length; + time->tv_sec = oops_hdr->timestamp; + time->tv_nsec = 0; + } *buf = kmalloc(length, GFP_KERNEL); if (*buf == NULL) return -ENOMEM; - memcpy(*buf, buff + sizeof(*oops_hdr), length); - time->tv_sec = oops_hdr->timestamp; - time->tv_nsec = 0; + memcpy(*buf, buff + hdr_size, length); kfree(buff); if (err_type == ERR_TYPE_KERNEL_PANIC_GZ) { -- cgit v0.10.2 From 144136dd7a25a0ca4d86685f872168502f91f337 Mon Sep 17 00:00:00 2001 From: Mike Qiu Date: Tue, 6 Aug 2013 22:25:14 -0400 Subject: powerpc/eeh: Add missing procfs entry for PowerNV The procfs entry for global statistics has been missed on PowerNV platform and the patch is going to add that. Signed-off-by: Mike Qiu Acked-by: Gavin Shan Signed-off-by: Benjamin Herrenschmidt diff --git a/arch/powerpc/kernel/eeh.c b/arch/powerpc/kernel/eeh.c index ea9414c8..55593ee 100644 --- a/arch/powerpc/kernel/eeh.c +++ b/arch/powerpc/kernel/eeh.c @@ -1061,7 +1061,7 @@ static const struct file_operations proc_eeh_operations = { static int __init eeh_init_proc(void) { - if (machine_is(pseries)) + if (machine_is(pseries) || machine_is(powernv)) proc_create("powerpc/eeh", 0, NULL, &proc_eeh_operations); return 0; } -- cgit v0.10.2 From 2fb10672c828f6e08f1dbe3690167300035adddc Mon Sep 17 00:00:00 2001 From: Chen Gang Date: Mon, 22 Jul 2013 14:32:35 +0800 Subject: powerpc/kvm: Add signed type cast for comparation 'rmls' is 'unsigned long', lpcr_rmls() will return negative number when failure occurs, so it need a type cast for comparing. 'lpid' is 'unsigned long', kvmppc_alloc_lpid() return negative number when failure occurs, so it need a type cast for comparing. Signed-off-by: Chen Gang Acked-by: Paul Mackerras Signed-off-by: Benjamin Herrenschmidt diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c index 2efa9dd..7629cd3 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -1809,7 +1809,7 @@ static int kvmppc_hv_setup_htab_rma(struct kvm_vcpu *vcpu) rma_size <<= PAGE_SHIFT; rmls = lpcr_rmls(rma_size); err = -EINVAL; - if (rmls < 0) { + if ((long)rmls < 0) { pr_err("KVM: Can't use RMA of 0x%lx bytes\n", rma_size); goto out_srcu; } @@ -1874,7 +1874,7 @@ int kvmppc_core_init_vm(struct kvm *kvm) /* Allocate the guest's logical partition ID */ lpid = kvmppc_alloc_lpid(); - if (lpid < 0) + if ((long)lpid < 0) return -ENOMEM; kvm->arch.lpid = lpid; -- cgit v0.10.2 From e0e13614626bfb5a88678fd951d728ed40e3cbf6 Mon Sep 17 00:00:00 2001 From: Thadeu Lima de Souza Cascardo Date: Wed, 17 Jul 2013 12:10:29 -0300 Subject: powerpc/kvm/book3s_pr: Return appropriate error when allocation fails err was overwritten by a previous function call, and checked to be 0. If the following page allocation fails, 0 is going to be returned instead of -ENOMEM. Signed-off-by: Thadeu Lima de Souza Cascardo Signed-off-by: Benjamin Herrenschmidt diff --git a/arch/powerpc/kvm/book3s_pr.c b/arch/powerpc/kvm/book3s_pr.c index 19498a5..c6e13d9 100644 --- a/arch/powerpc/kvm/book3s_pr.c +++ b/arch/powerpc/kvm/book3s_pr.c @@ -1047,11 +1047,12 @@ struct kvm_vcpu *kvmppc_core_vcpu_create(struct kvm *kvm, unsigned int id) if (err) goto free_shadow_vcpu; + err = -ENOMEM; p = __get_free_page(GFP_KERNEL|__GFP_ZERO); - /* the real shared page fills the last 4k of our page */ - vcpu->arch.shared = (void*)(p + PAGE_SIZE - 4096); if (!p) goto uninit_vcpu; + /* the real shared page fills the last 4k of our page */ + vcpu->arch.shared = (void *)(p + PAGE_SIZE - 4096); #ifdef CONFIG_PPC_BOOK3S_64 /* default to book3s_64 (970fx) */ -- cgit v0.10.2 From 88f094120bd2f012ff494ae50a8d4e0d8af8f69e Mon Sep 17 00:00:00 2001 From: Michael Neuling Date: Fri, 9 Aug 2013 17:29:27 +1000 Subject: powerpc: Fix hypervisor facility unavaliable vector number Currently if we take hypervisor facility unavaliable (from 0xf80/0x4f80) we mark it as an OS facility unavaliable (0xf60) as the two share the same code path. The becomes a problem in facility_unavailable_exception() as we aren't able to see the hypervisor facility unavailable exceptions. Below fixes this by duplication the required macros. Signed-off-by: Michael Neuling Cc: [v3.10] Signed-off-by: Benjamin Herrenschmidt diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S index 4e00d22..902ca3c 100644 --- a/arch/powerpc/kernel/exceptions-64s.S +++ b/arch/powerpc/kernel/exceptions-64s.S @@ -848,7 +848,7 @@ hv_facility_unavailable_relon_trampoline: . = 0x4f80 SET_SCRATCH0(r13) EXCEPTION_PROLOG_0(PACA_EXGEN) - b facility_unavailable_relon_hv + b hv_facility_unavailable_relon_hv STD_RELON_EXCEPTION_PSERIES(0x5300, 0x1300, instruction_breakpoint) #ifdef CONFIG_PPC_DENORMALISATION @@ -1175,6 +1175,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_VSX) b .ret_from_except STD_EXCEPTION_COMMON(0xf60, facility_unavailable, .facility_unavailable_exception) + STD_EXCEPTION_COMMON(0xf80, hv_facility_unavailable, .facility_unavailable_exception) .align 7 .globl __end_handlers @@ -1188,7 +1189,7 @@ __end_handlers: STD_RELON_EXCEPTION_PSERIES_OOL(0xf20, altivec_unavailable) STD_RELON_EXCEPTION_PSERIES_OOL(0xf40, vsx_unavailable) STD_RELON_EXCEPTION_PSERIES_OOL(0xf60, facility_unavailable) - STD_RELON_EXCEPTION_HV_OOL(0xf80, facility_unavailable) + STD_RELON_EXCEPTION_HV_OOL(0xf80, hv_facility_unavailable) #if defined(CONFIG_PPC_PSERIES) || defined(CONFIG_PPC_POWERNV) /* -- cgit v0.10.2 From 74e400cee6c0266ba2d940ed78d981f1e24a8167 Mon Sep 17 00:00:00 2001 From: Michael Neuling Date: Fri, 9 Aug 2013 17:29:28 +1000 Subject: powerpc: Rework setting up H/FSCR bit definitions This reworks the Facility Status and Control Regsiter (FSCR) config bit definitions so that we can access the bit numbers. This is needed for a subsequent patch to fix the userspace DSCR handling. HFSCR and FSCR bit definitions are the same, so reuse them. Signed-off-by: Michael Neuling Cc: [v3.10] Signed-off-by: Benjamin Herrenschmidt diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h index a6840e4..99222e2 100644 --- a/arch/powerpc/include/asm/reg.h +++ b/arch/powerpc/include/asm/reg.h @@ -254,19 +254,28 @@ #define SPRN_HRMOR 0x139 /* Real mode offset register */ #define SPRN_HSRR0 0x13A /* Hypervisor Save/Restore 0 */ #define SPRN_HSRR1 0x13B /* Hypervisor Save/Restore 1 */ +/* HFSCR and FSCR bit numbers are the same */ +#define FSCR_TAR_LG 8 /* Enable Target Address Register */ +#define FSCR_EBB_LG 7 /* Enable Event Based Branching */ +#define FSCR_TM_LG 5 /* Enable Transactional Memory */ +#define FSCR_PM_LG 4 /* Enable prob/priv access to PMU SPRs */ +#define FSCR_BHRB_LG 3 /* Enable Branch History Rolling Buffer*/ +#define FSCR_DSCR_LG 2 /* Enable Data Stream Control Register */ +#define FSCR_VECVSX_LG 1 /* Enable VMX/VSX */ +#define FSCR_FP_LG 0 /* Enable Floating Point */ #define SPRN_FSCR 0x099 /* Facility Status & Control Register */ -#define FSCR_TAR (1 << (63-55)) /* Enable Target Address Register */ -#define FSCR_EBB (1 << (63-56)) /* Enable Event Based Branching */ -#define FSCR_DSCR (1 << (63-61)) /* Enable Data Stream Control Register */ +#define FSCR_TAR __MASK(FSCR_TAR_LG) +#define FSCR_EBB __MASK(FSCR_EBB_LG) +#define FSCR_DSCR __MASK(FSCR_DSCR_LG) #define SPRN_HFSCR 0xbe /* HV=1 Facility Status & Control Register */ -#define HFSCR_TAR (1 << (63-55)) /* Enable Target Address Register */ -#define HFSCR_EBB (1 << (63-56)) /* Enable Event Based Branching */ -#define HFSCR_TM (1 << (63-58)) /* Enable Transactional Memory */ -#define HFSCR_PM (1 << (63-60)) /* Enable prob/priv access to PMU SPRs */ -#define HFSCR_BHRB (1 << (63-59)) /* Enable Branch History Rolling Buffer*/ -#define HFSCR_DSCR (1 << (63-61)) /* Enable Data Stream Control Register */ -#define HFSCR_VECVSX (1 << (63-62)) /* Enable VMX/VSX */ -#define HFSCR_FP (1 << (63-63)) /* Enable Floating Point */ +#define HFSCR_TAR __MASK(FSCR_TAR_LG) +#define HFSCR_EBB __MASK(FSCR_EBB_LG) +#define HFSCR_TM __MASK(FSCR_TM_LG) +#define HFSCR_PM __MASK(FSCR_PM_LG) +#define HFSCR_BHRB __MASK(FSCR_BHRB_LG) +#define HFSCR_DSCR __MASK(FSCR_DSCR_LG) +#define HFSCR_VECVSX __MASK(FSCR_VECVSX_LG) +#define HFSCR_FP __MASK(FSCR_FP_LG) #define SPRN_TAR 0x32f /* Target Address Register */ #define SPRN_LPCR 0x13E /* LPAR Control Register */ #define LPCR_VPM0 (1ul << (63-0)) -- cgit v0.10.2 From 2517617e0de65f8f7cfe75cae745d06b1fa98586 Mon Sep 17 00:00:00 2001 From: Michael Neuling Date: Fri, 9 Aug 2013 17:29:29 +1000 Subject: powerpc: Fix context switch DSCR on POWER8 POWER8 allows the DSCR to be accessed directly from userspace via a new SPR number 0x3 (Rather than 0x11. DSCR SPR number 0x11 is still used on POWER8 but like POWER7, is only accessible in HV and OS modes). Currently, we allow this by setting H/FSCR DSCR bit on boot. Unfortunately this doesn't work, as the kernel needs to see the DSCR change so that it knows to no longer restore the system wide version of DSCR on context switch (ie. to set thread.dscr_inherit). This clears the H/FSCR DSCR bit initially. If a process then accesses the DSCR (via SPR 0x3), it'll trap into the kernel where we set thread.dscr_inherit in facility_unavailable_exception(). We also change _switch() so that we set or clear the H/FSCR DSCR bit based on the thread.dscr_inherit. Signed-off-by: Michael Neuling Cc: [v3.10] Signed-off-by: Benjamin Herrenschmidt diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S index ab15b8d..4674fe6 100644 --- a/arch/powerpc/kernel/entry_64.S +++ b/arch/powerpc/kernel/entry_64.S @@ -584,9 +584,34 @@ BEGIN_FTR_SECTION ld r7,DSCR_DEFAULT@toc(2) ld r0,THREAD_DSCR(r4) cmpwi r6,0 + li r8, FSCR_DSCR bne 1f ld r0,0(r7) -1: cmpd r0,r25 + b 3f +1: + BEGIN_FTR_SECTION_NESTED(70) + mfspr r6, SPRN_FSCR + or r6, r6, r8 + mtspr SPRN_FSCR, r6 + BEGIN_FTR_SECTION_NESTED(69) + mfspr r6, SPRN_HFSCR + or r6, r6, r8 + mtspr SPRN_HFSCR, r6 + END_FTR_SECTION_NESTED(CPU_FTR_HVMODE, CPU_FTR_HVMODE, 69) + b 4f + END_FTR_SECTION_NESTED(CPU_FTR_ARCH_207S, CPU_FTR_ARCH_207S, 70) +3: + BEGIN_FTR_SECTION_NESTED(70) + mfspr r6, SPRN_FSCR + andc r6, r6, r8 + mtspr SPRN_FSCR, r6 + BEGIN_FTR_SECTION_NESTED(69) + mfspr r6, SPRN_HFSCR + andc r6, r6, r8 + mtspr SPRN_HFSCR, r6 + END_FTR_SECTION_NESTED(CPU_FTR_HVMODE, CPU_FTR_HVMODE, 69) + END_FTR_SECTION_NESTED(CPU_FTR_ARCH_207S, CPU_FTR_ARCH_207S, 70) +4: cmpd r0,r25 beq 2f mtspr SPRN_DSCR,r0 2: diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c index bf33c22..e435bc0 100644 --- a/arch/powerpc/kernel/traps.c +++ b/arch/powerpc/kernel/traps.c @@ -44,9 +44,7 @@ #include #include #include -#ifdef CONFIG_PPC32 #include -#endif #ifdef CONFIG_PMAC_BACKLIGHT #include #endif @@ -1296,43 +1294,54 @@ void vsx_unavailable_exception(struct pt_regs *regs) die("Unrecoverable VSX Unavailable Exception", regs, SIGABRT); } +#ifdef CONFIG_PPC64 void facility_unavailable_exception(struct pt_regs *regs) { static char *facility_strings[] = { - "FPU", - "VMX/VSX", - "DSCR", - "PMU SPRs", - "BHRB", - "TM", - "AT", - "EBB", - "TAR", + [FSCR_FP_LG] = "FPU", + [FSCR_VECVSX_LG] = "VMX/VSX", + [FSCR_DSCR_LG] = "DSCR", + [FSCR_PM_LG] = "PMU SPRs", + [FSCR_BHRB_LG] = "BHRB", + [FSCR_TM_LG] = "TM", + [FSCR_EBB_LG] = "EBB", + [FSCR_TAR_LG] = "TAR", }; - char *facility, *prefix; + char *facility = "unknown"; u64 value; + u8 status; + bool hv; - if (regs->trap == 0xf60) { - value = mfspr(SPRN_FSCR); - prefix = ""; - } else { + hv = (regs->trap == 0xf80); + if (hv) value = mfspr(SPRN_HFSCR); - prefix = "Hypervisor "; + else + value = mfspr(SPRN_FSCR); + + status = value >> 56; + if (status == FSCR_DSCR_LG) { + /* User is acessing the DSCR. Set the inherit bit and allow + * the user to set it directly in future by setting via the + * H/FSCR DSCR bit. + */ + current->thread.dscr_inherit = 1; + if (hv) + mtspr(SPRN_HFSCR, value | HFSCR_DSCR); + else + mtspr(SPRN_FSCR, value | FSCR_DSCR); + return; } - value = value >> 56; + if ((status < ARRAY_SIZE(facility_strings)) && + facility_strings[status]) + facility = facility_strings[status]; /* We restore the interrupt state now */ if (!arch_irq_disabled_regs(regs)) local_irq_enable(); - if (value < ARRAY_SIZE(facility_strings)) - facility = facility_strings[value]; - else - facility = "unknown"; - pr_err("%sFacility '%s' unavailable, exception at 0x%lx, MSR=%lx\n", - prefix, facility, regs->nip, regs->msr); + hv ? "Hypervisor " : "", facility, regs->nip, regs->msr); if (user_mode(regs)) { _exception(SIGILL, regs, ILL_ILLOPC, regs->nip); @@ -1341,6 +1350,7 @@ void facility_unavailable_exception(struct pt_regs *regs) die("Unexpected facility unavailable exception", regs, SIGABRT); } +#endif #ifdef CONFIG_PPC_TRANSACTIONAL_MEM -- cgit v0.10.2 From c2d52644e2da8a07ecab5ca62dd0bc563089e8dc Mon Sep 17 00:00:00 2001 From: Michael Neuling Date: Fri, 9 Aug 2013 17:29:30 +1000 Subject: powerpc: Save the TAR register earlier This moves us to save the Target Address Register (TAR) a earlier in __switch_to. It introduces a new function save_tar() to do this. We need to save the TAR earlier as we will overwrite it in the transactional memory reclaim/recheckpoint path. We are going to do this in a subsequent patch which will fix saving the TAR register when it's modified inside a transaction. Signed-off-by: Michael Neuling Cc: [v3.10] Signed-off-by: Benjamin Herrenschmidt diff --git a/arch/powerpc/include/asm/switch_to.h b/arch/powerpc/include/asm/switch_to.h index 49a13e0..294c2ce 100644 --- a/arch/powerpc/include/asm/switch_to.h +++ b/arch/powerpc/include/asm/switch_to.h @@ -15,6 +15,15 @@ extern struct task_struct *__switch_to(struct task_struct *, struct thread_struct; extern struct task_struct *_switch(struct thread_struct *prev, struct thread_struct *next); +#ifdef CONFIG_PPC_BOOK3S_64 +static inline void save_tar(struct thread_struct *prev) +{ + if (cpu_has_feature(CPU_FTR_ARCH_207S)) + prev->tar = mfspr(SPRN_TAR); +} +#else +static inline void save_tar(struct thread_struct *prev) {} +#endif extern void giveup_fpu(struct task_struct *); extern void load_up_fpu(void); diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S index 4674fe6..2bd0b88 100644 --- a/arch/powerpc/kernel/entry_64.S +++ b/arch/powerpc/kernel/entry_64.S @@ -449,15 +449,6 @@ END_FTR_SECTION_IFSET(CPU_FTR_DSCR) #ifdef CONFIG_PPC_BOOK3S_64 BEGIN_FTR_SECTION - /* - * Back up the TAR across context switches. Note that the TAR is not - * available for use in the kernel. (To provide this, the TAR should - * be backed up/restored on exception entry/exit instead, and be in - * pt_regs. FIXME, this should be in pt_regs anyway (for debug).) - */ - mfspr r0,SPRN_TAR - std r0,THREAD_TAR(r3) - /* Event based branch registers */ mfspr r0, SPRN_BESCR std r0, THREAD_BESCR(r3) diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c index c517dbe..8083be2 100644 --- a/arch/powerpc/kernel/process.c +++ b/arch/powerpc/kernel/process.c @@ -600,6 +600,16 @@ struct task_struct *__switch_to(struct task_struct *prev, struct ppc64_tlb_batch *batch; #endif + /* Back up the TAR across context switches. + * Note that the TAR is not available for use in the kernel. (To + * provide this, the TAR should be backed up/restored on exception + * entry/exit instead, and be in pt_regs. FIXME, this should be in + * pt_regs anyway (for debug).) + * Save the TAR here before we do treclaim/trecheckpoint as these + * will change the TAR. + */ + save_tar(&prev->thread); + __switch_to_tm(prev); #ifdef CONFIG_SMP -- cgit v0.10.2 From 28e61cc466d8daace4b0f04ba2b83e0bd68f5832 Mon Sep 17 00:00:00 2001 From: Michael Neuling Date: Fri, 9 Aug 2013 17:29:31 +1000 Subject: powerpc/tm: Fix context switching TAR, PPR and DSCR SPRs If a transaction is rolled back, the Target Address Register (TAR), Processor Priority Register (PPR) and Data Stream Control Register (DSCR) should be restored to the checkpointed values before the transaction began. Any changes to these SPRs inside the transaction should not be visible in the abort handler. Currently Linux doesn't save or restore the checkpointed TAR, PPR or DSCR. If we preempt a processes inside a transaction which has modified any of these, on process restore, that same transaction may be aborted we but we won't see the checkpointed versions of these SPRs. This adds checkpointed versions of these SPRs to the thread_struct and adds the save/restore of these three SPRs to the treclaim/trechkpt code. Without this if any of these SPRs are modified during a transaction, users may incorrectly see a speculated SPR value even if the transaction is aborted. Signed-off-by: Michael Neuling Cc: [v3.10] Signed-off-by: Benjamin Herrenschmidt diff --git a/arch/powerpc/include/asm/processor.h b/arch/powerpc/include/asm/processor.h index 47a35b0..e378ccc 100644 --- a/arch/powerpc/include/asm/processor.h +++ b/arch/powerpc/include/asm/processor.h @@ -247,6 +247,10 @@ struct thread_struct { unsigned long tm_orig_msr; /* Thread's MSR on ctx switch */ struct pt_regs ckpt_regs; /* Checkpointed registers */ + unsigned long tm_tar; + unsigned long tm_ppr; + unsigned long tm_dscr; + /* * Transactional FP and VSX 0-31 register set. * NOTE: the sense of these is the opposite of the integer ckpt_regs! diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c index c7e8afc..8207459 100644 --- a/arch/powerpc/kernel/asm-offsets.c +++ b/arch/powerpc/kernel/asm-offsets.c @@ -138,6 +138,9 @@ int main(void) DEFINE(THREAD_TM_TFHAR, offsetof(struct thread_struct, tm_tfhar)); DEFINE(THREAD_TM_TEXASR, offsetof(struct thread_struct, tm_texasr)); DEFINE(THREAD_TM_TFIAR, offsetof(struct thread_struct, tm_tfiar)); + DEFINE(THREAD_TM_TAR, offsetof(struct thread_struct, tm_tar)); + DEFINE(THREAD_TM_PPR, offsetof(struct thread_struct, tm_ppr)); + DEFINE(THREAD_TM_DSCR, offsetof(struct thread_struct, tm_dscr)); DEFINE(PT_CKPT_REGS, offsetof(struct thread_struct, ckpt_regs)); DEFINE(THREAD_TRANSACT_VR0, offsetof(struct thread_struct, transact_vr[0])); diff --git a/arch/powerpc/kernel/tm.S b/arch/powerpc/kernel/tm.S index 51be8fb..0554d1f 100644 --- a/arch/powerpc/kernel/tm.S +++ b/arch/powerpc/kernel/tm.S @@ -233,6 +233,16 @@ dont_backup_fp: std r5, _CCR(r7) std r6, _XER(r7) + + /* ******************** TAR, PPR, DSCR ********** */ + mfspr r3, SPRN_TAR + mfspr r4, SPRN_PPR + mfspr r5, SPRN_DSCR + + std r3, THREAD_TM_TAR(r12) + std r4, THREAD_TM_PPR(r12) + std r5, THREAD_TM_DSCR(r12) + /* MSR and flags: We don't change CRs, and we don't need to alter * MSR. */ @@ -347,6 +357,16 @@ dont_restore_fp: mtmsr r6 /* FP/Vec off again! */ restore_gprs: + + /* ******************** TAR, PPR, DSCR ********** */ + ld r4, THREAD_TM_TAR(r3) + ld r5, THREAD_TM_PPR(r3) + ld r6, THREAD_TM_DSCR(r3) + + mtspr SPRN_TAR, r4 + mtspr SPRN_PPR, r5 + mtspr SPRN_DSCR, r6 + /* ******************** CR,LR,CCR,MSR ********** */ ld r3, _CTR(r7) ld r4, _LINK(r7) -- cgit v0.10.2