From 18df7577adae6c6c778bf774b3aebcacbc1fb439 Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Sun, 9 Jun 2019 20:17:44 +0200 Subject: efi/memreserve: deal with memreserve entries in unmapped memory Ensure that the EFI memreserve entries can be accessed, even if they are located in memory that the kernel (e.g., a crashkernel) omits from the linear map. Fixes: 80424b02d42b ("efi: Reduce the amount of memblock reservations ...") Cc: # 5.0+ Reported-by: Jonathan Richardson Reviewed-by: Jonathan Richardson Tested-by: Jonathan Richardson Signed-off-by: Ard Biesheuvel --- drivers/firmware/efi/efi.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) (limited to 'drivers/firmware') diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index 16b2137d117c..4b7cf7bc0ded 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -1009,14 +1009,16 @@ int __ref efi_mem_reserve_persistent(phys_addr_t addr, u64 size) /* first try to find a slot in an existing linked list entry */ for (prsv = efi_memreserve_root->next; prsv; prsv = rsv->next) { - rsv = __va(prsv); + rsv = memremap(prsv, sizeof(*rsv), MEMREMAP_WB); index = atomic_fetch_add_unless(&rsv->count, 1, rsv->size); if (index < rsv->size) { rsv->entry[index].base = addr; rsv->entry[index].size = size; + memunmap(rsv); return 0; } + memunmap(rsv); } /* no slot found - allocate a new linked list entry */ @@ -1024,7 +1026,13 @@ int __ref efi_mem_reserve_persistent(phys_addr_t addr, u64 size) if (!rsv) return -ENOMEM; - rsv->size = EFI_MEMRESERVE_COUNT(PAGE_SIZE); + /* + * The memremap() call above assumes that a linux_efi_memreserve entry + * never crosses a page boundary, so let's ensure that this remains true + * even when kexec'ing a 4k pages kernel from a >4k pages kernel, by + * using SZ_4K explicitly in the size calculation below. + */ + rsv->size = EFI_MEMRESERVE_COUNT(SZ_4K); atomic_set(&rsv->count, 1); rsv->entry[0].base = addr; rsv->entry[0].size = size; -- cgit v1.2.3 From a483fcab38b43fb34a7f12ab1daadd3907f150e2 Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Wed, 29 May 2019 15:28:28 +0200 Subject: efi/bgrt: Drop BGRT status field reserved bits check Starting with ACPI 6.2 bits 1 and 2 of the BGRT status field are no longer reserved. These bits are now used to indicate if the image needs to be rotated before being displayed. The first device using these bits has now shown up (the GPD MicroPC) and the reserved bits check causes us to reject the valid BGRT table on this device. Rather then changing the reserved bits check, allowing only the 2 new bits, instead just completely remove it so that we do not end up with a similar problem when more bits are added in the future. Signed-off-by: Hans de Goede Signed-off-by: Ard Biesheuvel --- drivers/firmware/efi/efi-bgrt.c | 5 ----- 1 file changed, 5 deletions(-) (limited to 'drivers/firmware') diff --git a/drivers/firmware/efi/efi-bgrt.c b/drivers/firmware/efi/efi-bgrt.c index a2384184a7de..b07c17643210 100644 --- a/drivers/firmware/efi/efi-bgrt.c +++ b/drivers/firmware/efi/efi-bgrt.c @@ -47,11 +47,6 @@ void __init efi_bgrt_init(struct acpi_table_header *table) bgrt->version); goto out; } - if (bgrt->status & 0xfe) { - pr_notice("Ignoring BGRT: reserved status bits are non-zero %u\n", - bgrt->status); - goto out; - } if (bgrt->image_type != 0) { pr_notice("Ignoring BGRT: invalid image type %u (expected 0)\n", bgrt->image_type); -- cgit v1.2.3 From 975a6166a8584ee4a1b8bd93098e49dc101d7171 Mon Sep 17 00:00:00 2001 From: Tian Baofeng Date: Wed, 12 Jun 2019 16:18:10 +0800 Subject: efibc: Replace variable set function in notifier call Replace the variable set function from "efivar_entry_set" to "efivar_entry_set_safe" in efibc panic notifier. In safe function parameter "block" will set to false and will call "efivar_entry_set_nonblocking"to set efi variables. efivar_entry_set_nonblocking is guaranteed to not block and is suitable for calling from crash/panic handlers. In UEFI android platform, when warm reset happens, with this change, efibc will not block the reboot process. Otherwise, set variable will call queue work and send to other offlined cpus then cause another panic, finally will cause reboot failure. Signed-off-by: Tian Baofeng Signed-off-by: Luo XinanX Signed-off-by: Ard Biesheuvel --- drivers/firmware/efi/efibc.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) (limited to 'drivers/firmware') diff --git a/drivers/firmware/efi/efibc.c b/drivers/firmware/efi/efibc.c index 61e099826cbb..35dccc88ac0a 100644 --- a/drivers/firmware/efi/efibc.c +++ b/drivers/firmware/efi/efibc.c @@ -43,11 +43,13 @@ static int efibc_set_variable(const char *name, const char *value) efibc_str_to_str16(value, (efi_char16_t *)entry->var.Data); memcpy(&entry->var.VendorGuid, &guid, sizeof(guid)); - ret = efivar_entry_set(entry, - EFI_VARIABLE_NON_VOLATILE - | EFI_VARIABLE_BOOTSERVICE_ACCESS - | EFI_VARIABLE_RUNTIME_ACCESS, - size, entry->var.Data, NULL); + ret = efivar_entry_set_safe(entry->var.VariableName, + entry->var.VendorGuid, + EFI_VARIABLE_NON_VOLATILE + | EFI_VARIABLE_BOOTSERVICE_ACCESS + | EFI_VARIABLE_RUNTIME_ACCESS, + false, size, entry->var.Data); + if (ret) pr_err("failed to set %s EFI variable: 0x%x\n", name, ret); -- cgit v1.2.3