From b484079b9f520cc9a0797d885f1cd7f64b72b1b2 Mon Sep 17 00:00:00 2001 From: James Morse Date: Tue, 29 Jan 2019 18:48:52 +0000 Subject: ACPI / APEI: Let the notification helper specify the fixmap slot ghes_copy_tofrom_phys() uses a different fixmap slot depending on in_nmi(). This doesn't work when there are multiple NMI-like notifications, that could interrupt each other. As with the locking, move the chosen fixmap_idx to the notification helper. This only matters for NMI-like notifications, anything calling ghes_proc() can use the IRQ fixmap slot as its already holding an irqsave spinlock. This lets us collapse the ghes_ioremap_pfn_*() helpers. Signed-off-by: James Morse Reviewed-by: Borislav Petkov Signed-off-by: Rafael J. Wysocki --- drivers/acpi/apei/ghes.c | 92 ++++++++++++++++++++---------------------------- 1 file changed, 39 insertions(+), 53 deletions(-) (limited to 'drivers/acpi/apei') diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c index c7dbdb915e7e..9a24641adfba 100644 --- a/drivers/acpi/apei/ghes.c +++ b/drivers/acpi/apei/ghes.c @@ -41,6 +41,7 @@ #include #include #include +#include #include #include #include @@ -127,38 +128,24 @@ static atomic_t ghes_estatus_cache_alloced; static int ghes_panic_timeout __read_mostly = 30; -static void __iomem *ghes_ioremap_pfn_nmi(u64 pfn) +static void __iomem *ghes_map(u64 pfn, enum fixed_addresses fixmap_idx) { phys_addr_t paddr; pgprot_t prot; - paddr = pfn << PAGE_SHIFT; + paddr = PFN_PHYS(pfn); prot = arch_apei_get_mem_attribute(paddr); - __set_fixmap(FIX_APEI_GHES_NMI, paddr, prot); + __set_fixmap(fixmap_idx, paddr, prot); - return (void __iomem *) fix_to_virt(FIX_APEI_GHES_NMI); + return (void __iomem *) __fix_to_virt(fixmap_idx); } -static void __iomem *ghes_ioremap_pfn_irq(u64 pfn) +static void ghes_unmap(void __iomem *vaddr, enum fixed_addresses fixmap_idx) { - phys_addr_t paddr; - pgprot_t prot; - - paddr = pfn << PAGE_SHIFT; - prot = arch_apei_get_mem_attribute(paddr); - __set_fixmap(FIX_APEI_GHES_IRQ, paddr, prot); + int _idx = virt_to_fix((unsigned long)vaddr); - return (void __iomem *) fix_to_virt(FIX_APEI_GHES_IRQ); -} - -static void ghes_iounmap_nmi(void) -{ - clear_fixmap(FIX_APEI_GHES_NMI); -} - -static void ghes_iounmap_irq(void) -{ - clear_fixmap(FIX_APEI_GHES_IRQ); + WARN_ON_ONCE(fixmap_idx != _idx); + clear_fixmap(fixmap_idx); } int ghes_estatus_pool_init(int num_ghes) @@ -283,20 +270,16 @@ static inline int ghes_severity(int severity) } static void ghes_copy_tofrom_phys(void *buffer, u64 paddr, u32 len, - int from_phys) + int from_phys, + enum fixed_addresses fixmap_idx) { void __iomem *vaddr; - int in_nmi = in_nmi(); u64 offset; u32 trunk; while (len > 0) { offset = paddr - (paddr & PAGE_MASK); - if (in_nmi) { - vaddr = ghes_ioremap_pfn_nmi(paddr >> PAGE_SHIFT); - } else { - vaddr = ghes_ioremap_pfn_irq(paddr >> PAGE_SHIFT); - } + vaddr = ghes_map(PHYS_PFN(paddr), fixmap_idx); trunk = PAGE_SIZE - offset; trunk = min(trunk, len); if (from_phys) @@ -306,15 +289,13 @@ static void ghes_copy_tofrom_phys(void *buffer, u64 paddr, u32 len, len -= trunk; paddr += trunk; buffer += trunk; - if (in_nmi) { - ghes_iounmap_nmi(); - } else { - ghes_iounmap_irq(); - } + ghes_unmap(vaddr, fixmap_idx); } } -static int ghes_read_estatus(struct ghes *ghes, u64 *buf_paddr) +static int ghes_read_estatus(struct ghes *ghes, u64 *buf_paddr, + enum fixed_addresses fixmap_idx) + { struct acpi_hest_generic *g = ghes->generic; u32 len; @@ -332,7 +313,7 @@ static int ghes_read_estatus(struct ghes *ghes, u64 *buf_paddr) return -ENOENT; ghes_copy_tofrom_phys(ghes->estatus, *buf_paddr, - sizeof(*ghes->estatus), 1); + sizeof(*ghes->estatus), 1, fixmap_idx); if (!ghes->estatus->block_status) { *buf_paddr = 0; return -ENOENT; @@ -348,7 +329,7 @@ static int ghes_read_estatus(struct ghes *ghes, u64 *buf_paddr) goto err_read_block; ghes_copy_tofrom_phys(ghes->estatus + 1, *buf_paddr + sizeof(*ghes->estatus), - len - sizeof(*ghes->estatus), 1); + len - sizeof(*ghes->estatus), 1, fixmap_idx); if (cper_estatus_check(ghes->estatus)) goto err_read_block; rc = 0; @@ -361,7 +342,8 @@ err_read_block: return rc; } -static void ghes_clear_estatus(struct ghes *ghes, u64 buf_paddr) +static void ghes_clear_estatus(struct ghes *ghes, u64 buf_paddr, + enum fixed_addresses fixmap_idx) { ghes->estatus->block_status = 0; @@ -369,7 +351,8 @@ static void ghes_clear_estatus(struct ghes *ghes, u64 buf_paddr) return; ghes_copy_tofrom_phys(ghes->estatus, buf_paddr, - sizeof(ghes->estatus->block_status), 0); + sizeof(ghes->estatus->block_status), 0, + fixmap_idx); /* * GHESv2 type HEST entries introduce support for error acknowledgment, @@ -668,11 +651,12 @@ static void ghes_estatus_cache_add( rcu_read_unlock(); } -static void __ghes_panic(struct ghes *ghes, u64 buf_paddr) +static void __ghes_panic(struct ghes *ghes, u64 buf_paddr, + enum fixed_addresses fixmap_idx) { __ghes_print_estatus(KERN_EMERG, ghes->generic, ghes->estatus); - ghes_clear_estatus(ghes, buf_paddr); + ghes_clear_estatus(ghes, buf_paddr, fixmap_idx); /* reboot to log the error! */ if (!panic_timeout) @@ -685,12 +669,12 @@ static int ghes_proc(struct ghes *ghes) u64 buf_paddr; int rc; - rc = ghes_read_estatus(ghes, &buf_paddr); + rc = ghes_read_estatus(ghes, &buf_paddr, FIX_APEI_GHES_IRQ); if (rc) goto out; if (ghes_severity(ghes->estatus->error_severity) >= GHES_SEV_PANIC) { - __ghes_panic(ghes, buf_paddr); + __ghes_panic(ghes, buf_paddr, FIX_APEI_GHES_IRQ); } if (!ghes_estatus_cached(ghes->estatus)) { @@ -700,7 +684,7 @@ static int ghes_proc(struct ghes *ghes) ghes_do_proc(ghes, ghes->estatus); out: - ghes_clear_estatus(ghes, buf_paddr); + ghes_clear_estatus(ghes, buf_paddr, FIX_APEI_GHES_IRQ); return rc; } @@ -866,36 +850,38 @@ static void __process_error(struct ghes *ghes) #endif } -static int ghes_in_nmi_queue_one_entry(struct ghes *ghes) +static int ghes_in_nmi_queue_one_entry(struct ghes *ghes, + enum fixed_addresses fixmap_idx) { u64 buf_paddr; int sev; - if (ghes_read_estatus(ghes, &buf_paddr)) { - ghes_clear_estatus(ghes, buf_paddr); + if (ghes_read_estatus(ghes, &buf_paddr, fixmap_idx)) { + ghes_clear_estatus(ghes, buf_paddr, fixmap_idx); return -ENOENT; } sev = ghes_severity(ghes->estatus->error_severity); if (sev >= GHES_SEV_PANIC) { ghes_print_queued_estatus(); - __ghes_panic(ghes, buf_paddr); + __ghes_panic(ghes, buf_paddr, fixmap_idx); } __process_error(ghes); - ghes_clear_estatus(ghes, buf_paddr); + ghes_clear_estatus(ghes, buf_paddr, fixmap_idx); return 0; } -static int ghes_in_nmi_spool_from_list(struct list_head *rcu_list) +static int ghes_in_nmi_spool_from_list(struct list_head *rcu_list, + enum fixed_addresses fixmap_idx) { int ret = -ENOENT; struct ghes *ghes; rcu_read_lock(); list_for_each_entry_rcu(ghes, rcu_list, list) { - if (!ghes_in_nmi_queue_one_entry(ghes)) + if (!ghes_in_nmi_queue_one_entry(ghes, fixmap_idx)) ret = 0; } rcu_read_unlock(); @@ -919,7 +905,7 @@ int ghes_notify_sea(void) int rv; raw_spin_lock(&ghes_notify_lock_sea); - rv = ghes_in_nmi_spool_from_list(&ghes_sea); + rv = ghes_in_nmi_spool_from_list(&ghes_sea, FIX_APEI_GHES_NMI); raw_spin_unlock(&ghes_notify_lock_sea); return rv; @@ -962,7 +948,7 @@ static int ghes_notify_nmi(unsigned int cmd, struct pt_regs *regs) return ret; raw_spin_lock(&ghes_notify_lock_nmi); - if (!ghes_in_nmi_spool_from_list(&ghes_nmi)) + if (!ghes_in_nmi_spool_from_list(&ghes_nmi, FIX_APEI_GHES_NMI)) ret = NMI_HANDLED; raw_spin_unlock(&ghes_notify_lock_nmi); -- cgit v1.2.3