From 402ff5a3387dc8ec6987a80d3ce26b0c25773622 Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Thu, 25 Nov 2021 19:59:16 +0100 Subject: s390/nmi: add missing __pa/__va address conversion of extended save area Add missing __pa/__va address conversion of machine check extended save area designation, which is an absolute address. Note: this currently doesn't fix a real bug, since virtual addresses are indentical to physical ones. Reported-by: Vineeth Vijayan Tested-by: Vineeth Vijayan Signed-off-by: Heiko Carstens --- arch/s390/kernel/smp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/s390/kernel/smp.c') diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c index 78a8ea6fd582..2e280e812dfd 100644 --- a/arch/s390/kernel/smp.c +++ b/arch/s390/kernel/smp.c @@ -622,7 +622,7 @@ int smp_store_status(int cpu) return -EIO; if (!MACHINE_HAS_VX && !MACHINE_HAS_GS) return 0; - pa = __pa(lc->mcesad & MCESA_ORIGIN_MASK); + pa = lc->mcesad & MCESA_ORIGIN_MASK; if (MACHINE_HAS_GS) pa |= lc->mcesad & MCESA_LC_MASK; if (__pcpu_sigp_relax(pcpu->address, SIGP_STORE_ADDITIONAL_STATUS, -- cgit v1.2.3 From fcfcba6dfc9a57da9c816667c20614ddfd4def10 Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Mon, 13 Dec 2021 19:00:57 +0100 Subject: s390/smp: fix memblock_phys_free() vs memblock_free() confusion memblock_phys_free() is used on a virtual address. Fix this by using memblock_free(). Note: this doesn't fix a bug currently, since virtual and physical addresses are identical. Reviewed-by: Alexander Gordeev Signed-off-by: Heiko Carstens --- arch/s390/kernel/smp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/s390/kernel/smp.c') diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c index 2e280e812dfd..2590c31a8fc3 100644 --- a/arch/s390/kernel/smp.c +++ b/arch/s390/kernel/smp.c @@ -880,7 +880,7 @@ void __init smp_detect_cpus(void) /* Add CPUs present at boot */ __smp_rescan_cpus(info, true); - memblock_phys_free((unsigned long)info, sizeof(*info)); + memblock_free(info, sizeof(*info)); } /* -- cgit v1.2.3 From c7ed509b21b6566990ff39a6744cd5e214b5dca9 Mon Sep 17 00:00:00 2001 From: Alexander Gordeev Date: Fri, 10 Dec 2021 16:32:11 +0100 Subject: s390/nmi: disable interrupts on extended save area update Updating of the pointer to machine check extended save area on the IPL CPU needs the lowcore protection to be disabled. Disable interrupts while the protection is off to avoid unnoticed writes to the lowcore. Suggested-by: Heiko Carstens Signed-off-by: Alexander Gordeev Signed-off-by: Heiko Carstens --- arch/s390/include/asm/nmi.h | 6 +++--- arch/s390/kernel/nmi.c | 41 ++++++++++++++++------------------------- arch/s390/kernel/setup.c | 2 +- arch/s390/kernel/smp.c | 13 +++++++++---- 4 files changed, 29 insertions(+), 33 deletions(-) (limited to 'arch/s390/kernel/smp.c') diff --git a/arch/s390/include/asm/nmi.h b/arch/s390/include/asm/nmi.h index 2db45d7e68aa..55c9051dddfd 100644 --- a/arch/s390/include/asm/nmi.h +++ b/arch/s390/include/asm/nmi.h @@ -98,9 +98,9 @@ struct mcesa { struct pt_regs; -void nmi_alloc_boot_cpu(struct lowcore *lc); -int nmi_alloc_per_cpu(struct lowcore *lc); -void nmi_free_per_cpu(struct lowcore *lc); +void nmi_alloc_mcesa_early(u64 *mcesad); +int nmi_alloc_mcesa(u64 *mcesad); +void nmi_free_mcesa(u64 *mcesad); void s390_handle_mcck(void); void __s390_handle_mcck(void); diff --git a/arch/s390/kernel/nmi.c b/arch/s390/kernel/nmi.c index 3f18c1412eba..1cf1e37553e8 100644 --- a/arch/s390/kernel/nmi.c +++ b/arch/s390/kernel/nmi.c @@ -58,27 +58,27 @@ static inline unsigned long nmi_get_mcesa_size(void) /* * The initial machine check extended save area for the boot CPU. - * It will be replaced by nmi_init() with an allocated structure. - * The structure is required for machine check happening early in - * the boot process. + * It will be replaced on the boot CPU reinit with an allocated + * structure. The structure is required for machine check happening + * early in the boot process. */ static struct mcesa boot_mcesa __initdata __aligned(MCESA_MAX_SIZE); -void __init nmi_alloc_boot_cpu(struct lowcore *lc) +void __init nmi_alloc_mcesa_early(u64 *mcesad) { if (!nmi_needs_mcesa()) return; - lc->mcesad = __pa(&boot_mcesa); + *mcesad = __pa(&boot_mcesa); if (MACHINE_HAS_GS) - lc->mcesad |= ilog2(MCESA_MAX_SIZE); + *mcesad |= ilog2(MCESA_MAX_SIZE); } -static int __init nmi_init(void) +static void __init nmi_alloc_cache(void) { - unsigned long origin, cr0, size; + unsigned long size; if (!nmi_needs_mcesa()) - return 0; + return; size = nmi_get_mcesa_size(); if (size > MCESA_MIN_SIZE) mcesa_origin_lc = ilog2(size); @@ -86,40 +86,31 @@ static int __init nmi_init(void) mcesa_cache = kmem_cache_create("nmi_save_areas", size, size, 0, NULL); if (!mcesa_cache) panic("Couldn't create nmi save area cache"); - origin = (unsigned long) kmem_cache_alloc(mcesa_cache, GFP_KERNEL); - if (!origin) - panic("Couldn't allocate nmi save area"); - /* The pointer is stored with mcesa_bits ORed in */ - kmemleak_not_leak((void *) origin); - __ctl_store(cr0, 0, 0); - __ctl_clear_bit(0, 28); /* disable lowcore protection */ - /* Replace boot_mcesa on the boot CPU */ - S390_lowcore.mcesad = __pa(origin) | mcesa_origin_lc; - __ctl_load(cr0, 0, 0); - return 0; } -early_initcall(nmi_init); -int nmi_alloc_per_cpu(struct lowcore *lc) +int __ref nmi_alloc_mcesa(u64 *mcesad) { unsigned long origin; + *mcesad = 0; if (!nmi_needs_mcesa()) return 0; + if (!mcesa_cache) + nmi_alloc_cache(); origin = (unsigned long) kmem_cache_alloc(mcesa_cache, GFP_KERNEL); if (!origin) return -ENOMEM; /* The pointer is stored with mcesa_bits ORed in */ kmemleak_not_leak((void *) origin); - lc->mcesad = __pa(origin) | mcesa_origin_lc; + *mcesad = __pa(origin) | mcesa_origin_lc; return 0; } -void nmi_free_per_cpu(struct lowcore *lc) +void nmi_free_mcesa(u64 *mcesad) { if (!nmi_needs_mcesa()) return; - kmem_cache_free(mcesa_cache, __va(lc->mcesad & MCESA_ORIGIN_MASK)); + kmem_cache_free(mcesa_cache, __va(*mcesad & MCESA_ORIGIN_MASK)); } static notrace void s390_handle_damage(void) diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c index 225ab2d0a4c6..f2c25d113e7b 100644 --- a/arch/s390/kernel/setup.c +++ b/arch/s390/kernel/setup.c @@ -445,7 +445,7 @@ static void __init setup_lowcore_dat_off(void) lc->lpp = LPP_MAGIC; lc->machine_flags = S390_lowcore.machine_flags; lc->preempt_count = S390_lowcore.preempt_count; - nmi_alloc_boot_cpu(lc); + nmi_alloc_mcesa_early(&lc->mcesad); lc->sys_enter_timer = S390_lowcore.sys_enter_timer; lc->exit_timer = S390_lowcore.exit_timer; lc->user_timer = S390_lowcore.user_timer; diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c index 2590c31a8fc3..1172aaf0b7e2 100644 --- a/arch/s390/kernel/smp.c +++ b/arch/s390/kernel/smp.c @@ -212,7 +212,7 @@ static int pcpu_alloc_lowcore(struct pcpu *pcpu, int cpu) lc->return_lpswe = gen_lpswe(__LC_RETURN_PSW); lc->return_mcck_lpswe = gen_lpswe(__LC_RETURN_MCCK_PSW); lc->preempt_count = PREEMPT_DISABLED; - if (nmi_alloc_per_cpu(lc)) + if (nmi_alloc_mcesa(&lc->mcesad)) goto out; lowcore_ptr[cpu] = lc; pcpu_sigp_retry(pcpu, SIGP_SET_PREFIX, (u32)(unsigned long) lc); @@ -239,7 +239,7 @@ static void pcpu_free_lowcore(struct pcpu *pcpu) mcck_stack = lc->mcck_stack - STACK_INIT_OFFSET; pcpu_sigp_retry(pcpu, SIGP_SET_PREFIX, 0); lowcore_ptr[cpu] = NULL; - nmi_free_per_cpu(lc); + nmi_free_mcesa(&lc->mcesad); stack_free(async_stack); stack_free(mcck_stack); free_pages(nodat_stack, THREAD_SIZE_ORDER); @@ -1271,14 +1271,15 @@ static int __init smp_reinit_ipl_cpu(void) { unsigned long async_stack, nodat_stack, mcck_stack; struct lowcore *lc, *lc_ipl; - unsigned long flags; + unsigned long flags, cr0; + u64 mcesad; lc_ipl = lowcore_ptr[0]; lc = (struct lowcore *) __get_free_pages(GFP_KERNEL | GFP_DMA, LC_ORDER); nodat_stack = __get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER); async_stack = stack_alloc(); mcck_stack = stack_alloc(); - if (!lc || !nodat_stack || !async_stack || !mcck_stack) + if (!lc || !nodat_stack || !async_stack || !mcck_stack || nmi_alloc_mcesa(&mcesad)) panic("Couldn't allocate memory"); local_irq_save(flags); @@ -1287,6 +1288,10 @@ static int __init smp_reinit_ipl_cpu(void) S390_lowcore.nodat_stack = nodat_stack + STACK_INIT_OFFSET; S390_lowcore.async_stack = async_stack + STACK_INIT_OFFSET; S390_lowcore.mcck_stack = mcck_stack + STACK_INIT_OFFSET; + __ctl_store(cr0, 0, 0); + __ctl_clear_bit(0, 28); /* disable lowcore protection */ + S390_lowcore.mcesad = mcesad; + __ctl_load(cr0, 0, 0); lowcore_ptr[0] = lc; local_mcck_enable(); local_irq_restore(flags); -- cgit v1.2.3 From a0e45d40d5f8461aeee9374c0ffa7b1da87c203c Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Thu, 16 Dec 2021 13:27:10 +0100 Subject: s390/crash_dump: fix virtual vs physical address handling Signal processor STORE STATUS requires a physical address where register contents are supposed to be written to, however the kernel must read the data via the corresponding virtual address. Also the allocated save_area, where register contents are copied to, resides in virtual address space. Fix this by using proper __pa() conversion, or correct memblock_alloc() invocation. Reviewed-by: Alexander Gordeev Signed-off-by: Heiko Carstens --- arch/s390/kernel/crash_dump.c | 2 +- arch/s390/kernel/smp.c | 18 +++++++----------- 2 files changed, 8 insertions(+), 12 deletions(-) (limited to 'arch/s390/kernel/smp.c') diff --git a/arch/s390/kernel/crash_dump.c b/arch/s390/kernel/crash_dump.c index 785d54c9350c..af8202121642 100644 --- a/arch/s390/kernel/crash_dump.c +++ b/arch/s390/kernel/crash_dump.c @@ -60,7 +60,7 @@ struct save_area * __init save_area_alloc(bool is_boot_cpu) { struct save_area *sa; - sa = (void *) memblock_phys_alloc(sizeof(*sa), 8); + sa = memblock_alloc(sizeof(*sa), 8); if (!sa) panic("Failed to allocate save area\n"); diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c index 1172aaf0b7e2..2bad902d8437 100644 --- a/arch/s390/kernel/smp.c +++ b/arch/s390/kernel/smp.c @@ -658,26 +658,22 @@ int smp_store_status(int cpu) * deactivates the elfcorehdr= kernel parameter */ static __init void smp_save_cpu_vxrs(struct save_area *sa, u16 addr, - bool is_boot_cpu, unsigned long page) + bool is_boot_cpu, __vector128 *vxrs) { - __vector128 *vxrs = (__vector128 *) page; - if (is_boot_cpu) vxrs = boot_cpu_vector_save_area; else - __pcpu_sigp_relax(addr, SIGP_STORE_ADDITIONAL_STATUS, page); + __pcpu_sigp_relax(addr, SIGP_STORE_ADDITIONAL_STATUS, __pa(vxrs)); save_area_add_vxrs(sa, vxrs); } static __init void smp_save_cpu_regs(struct save_area *sa, u16 addr, - bool is_boot_cpu, unsigned long page) + bool is_boot_cpu, void *regs) { - void *regs = (void *) page; - if (is_boot_cpu) copy_oldmem_kernel(regs, (void *) __LC_FPREGS_SAVE_AREA, 512); else - __pcpu_sigp_relax(addr, SIGP_STORE_STATUS_AT_ADDRESS, page); + __pcpu_sigp_relax(addr, SIGP_STORE_STATUS_AT_ADDRESS, __pa(regs)); save_area_add_regs(sa, regs); } @@ -685,14 +681,14 @@ void __init smp_save_dump_cpus(void) { int addr, boot_cpu_addr, max_cpu_addr; struct save_area *sa; - unsigned long page; bool is_boot_cpu; + void *page; if (!(oldmem_data.start || is_ipl_type_dump())) /* No previous system present, normal boot. */ return; /* Allocate a page as dumping area for the store status sigps */ - page = memblock_phys_alloc_range(PAGE_SIZE, PAGE_SIZE, 0, 1UL << 31); + page = memblock_alloc_low(PAGE_SIZE, PAGE_SIZE); if (!page) panic("ERROR: Failed to allocate %lx bytes below %lx\n", PAGE_SIZE, 1UL << 31); @@ -723,7 +719,7 @@ void __init smp_save_dump_cpus(void) /* Get the CPU registers */ smp_save_cpu_regs(sa, addr, is_boot_cpu, page); } - memblock_phys_free(page, PAGE_SIZE); + memblock_free(page, PAGE_SIZE); diag_amode31_ops.diag308_reset(); pcpu_set_smt(0); } -- cgit v1.2.3