From ef1491e791308317bb9851a0ad380c4a68b58d54 Mon Sep 17 00:00:00 2001 From: Waiman Long Date: Wed, 14 Nov 2018 09:55:40 -0800 Subject: [PATCH 1/5] efi: Fix debugobjects warning on 'efi_rts_work' The following commit: 9dbbedaa6171 ("efi: Make efi_rts_work accessible to efi page fault handler") converted 'efi_rts_work' from an auto variable to a global variable. However, when submitting the work, INIT_WORK_ONSTACK() was still used, causing the following complaint from debugobjects: ODEBUG: object 00000000ed27b500 is NOT on stack 00000000c7d38760, but annotated. Change the macro to just INIT_WORK() to eliminate the warning. Signed-off-by: Waiman Long Signed-off-by: Ard Biesheuvel Acked-by: Sai Praneeth Prakhya Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Fixes: 9dbbedaa6171 ("efi: Make efi_rts_work accessible to efi page fault handler") Link: http://lkml.kernel.org/r/20181114175544.12860-2-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar --- drivers/firmware/efi/runtime-wrappers.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/firmware/efi/runtime-wrappers.c b/drivers/firmware/efi/runtime-wrappers.c index a19d845bdb06..8903b9ccfc2b 100644 --- a/drivers/firmware/efi/runtime-wrappers.c +++ b/drivers/firmware/efi/runtime-wrappers.c @@ -67,7 +67,7 @@ struct efi_runtime_work efi_rts_work; } \ \ init_completion(&efi_rts_work.efi_rts_comp); \ - INIT_WORK_ONSTACK(&efi_rts_work.work, efi_call_rts); \ + INIT_WORK(&efi_rts_work.work, efi_call_rts); \ efi_rts_work.arg1 = _arg1; \ efi_rts_work.arg2 = _arg2; \ efi_rts_work.arg3 = _arg3; \ From 33412b8673135b18ea42beb7f5117ed0091798b6 Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Wed, 14 Nov 2018 09:55:41 -0800 Subject: [PATCH 2/5] efi/arm: Revert deferred unmap of early memmap mapping Commit: 3ea86495aef2 ("efi/arm: preserve early mapping of UEFI memory map longer for BGRT") deferred the unmap of the early mapping of the UEFI memory map to accommodate the ACPI BGRT code, which looks up the memory type that backs the BGRT table to validate it against the requirements of the UEFI spec. Unfortunately, this causes problems on ARM, which does not permit early mappings to persist after paging_init() is called, resulting in a WARN() splat. Since we don't support the BGRT table on ARM anway, let's revert ARM to the old behaviour, which is to take down the early mapping at the end of efi_init(). Signed-off-by: Ard Biesheuvel Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Fixes: 3ea86495aef2 ("efi/arm: preserve early mapping of UEFI memory ...") Link: http://lkml.kernel.org/r/20181114175544.12860-3-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar --- drivers/firmware/efi/arm-init.c | 4 ++++ drivers/firmware/efi/arm-runtime.c | 2 +- drivers/firmware/efi/memmap.c | 3 +++ 3 files changed, 8 insertions(+), 1 deletion(-) diff --git a/drivers/firmware/efi/arm-init.c b/drivers/firmware/efi/arm-init.c index 388a929baf95..1a6a77df8a5e 100644 --- a/drivers/firmware/efi/arm-init.c +++ b/drivers/firmware/efi/arm-init.c @@ -265,6 +265,10 @@ void __init efi_init(void) (params.mmap & ~PAGE_MASK))); init_screen_info(); + + /* ARM does not permit early mappings to persist across paging_init() */ + if (IS_ENABLED(CONFIG_ARM)) + efi_memmap_unmap(); } static int __init register_gop_device(void) diff --git a/drivers/firmware/efi/arm-runtime.c b/drivers/firmware/efi/arm-runtime.c index 922cfb813109..a00934d263c5 100644 --- a/drivers/firmware/efi/arm-runtime.c +++ b/drivers/firmware/efi/arm-runtime.c @@ -110,7 +110,7 @@ static int __init arm_enable_runtime_services(void) { u64 mapsize; - if (!efi_enabled(EFI_BOOT) || !efi_enabled(EFI_MEMMAP)) { + if (!efi_enabled(EFI_BOOT)) { pr_info("EFI services will not be available.\n"); return 0; } diff --git a/drivers/firmware/efi/memmap.c b/drivers/firmware/efi/memmap.c index fa2904fb841f..38b686c67b17 100644 --- a/drivers/firmware/efi/memmap.c +++ b/drivers/firmware/efi/memmap.c @@ -118,6 +118,9 @@ int __init efi_memmap_init_early(struct efi_memory_map_data *data) void __init efi_memmap_unmap(void) { + if (!efi_enabled(EFI_MEMMAP)) + return; + if (!efi.memmap.late) { unsigned long size; From 72a58a63a164b4e9d2d914e65caeb551846883f1 Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Wed, 14 Nov 2018 09:55:42 -0800 Subject: [PATCH 3/5] efi/arm/libstub: Pack FDT after populating it Commit: 24d7c494ce46 ("efi/arm-stub: Round up FDT allocation to mapping size") increased the allocation size for the FDT image created by the stub to a fixed value of 2 MB, to simplify the former code that made several attempts with increasing values for the size. This is reasonable given that the allocation is of type EFI_LOADER_DATA, which is released to the kernel unless it is explicitly memblock_reserve()d by the early boot code. However, this allocation size leaked into the 'size' field of the FDT header metadata, and so the entire allocation remains occupied by the device tree binary, even if most of it is not used to store device tree information. So call fdt_pack() to shrink the FDT data structure to its minimum size after populating all the fields, so that the remaining memory is no longer wasted. Signed-off-by: Ard Biesheuvel Cc: # v4.12+ Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Fixes: 24d7c494ce46 ("efi/arm-stub: Round up FDT allocation to mapping size") Link: http://lkml.kernel.org/r/20181114175544.12860-4-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar --- drivers/firmware/efi/libstub/fdt.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/firmware/efi/libstub/fdt.c b/drivers/firmware/efi/libstub/fdt.c index 8830fa601e45..0c0d2312f4a8 100644 --- a/drivers/firmware/efi/libstub/fdt.c +++ b/drivers/firmware/efi/libstub/fdt.c @@ -158,6 +158,10 @@ static efi_status_t update_fdt(efi_system_table_t *sys_table, void *orig_fdt, return efi_status; } } + + /* shrink the FDT back to its minimum size */ + fdt_pack(fdt); + return EFI_SUCCESS; fdt_set_fail: From eff896288872d687d9662000ec9ae11b6d61766f Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Wed, 14 Nov 2018 09:55:43 -0800 Subject: [PATCH 4/5] efi/arm: Defer persistent reservations until after paging_init() The new memory EFI reservation feature we introduced to allow memory reservations to persist across kexec may trigger an unbounded number of calls to memblock_reserve(). The memblock subsystem can deal with this fine, but not before memblock resizing is enabled, which we can only do after paging_init(), when the memory we reallocate the array into is actually mapped. So break out the memreserve table processing into a separate routine and call it after paging_init() on arm64. On ARM, because of limited reviewing bandwidth of the maintainer, we cannot currently fix this, so instead, disable the EFI persistent memreserve entirely on ARM so we can fix it later. Tested-by: Marc Zyngier Signed-off-by: Ard Biesheuvel Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/20181114175544.12860-5-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar --- arch/arm64/kernel/setup.c | 1 + drivers/firmware/efi/efi.c | 4 ++++ drivers/firmware/efi/libstub/arm-stub.c | 3 +++ include/linux/efi.h | 7 +++++++ 4 files changed, 15 insertions(+) diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c index 953e316521fc..f4fc1e0544b7 100644 --- a/arch/arm64/kernel/setup.c +++ b/arch/arm64/kernel/setup.c @@ -313,6 +313,7 @@ void __init setup_arch(char **cmdline_p) arm64_memblock_init(); paging_init(); + efi_apply_persistent_mem_reservations(); acpi_table_upgrade(); diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index 249eb70691b0..72a4da76d274 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -592,7 +592,11 @@ int __init efi_config_parse_tables(void *config_tables, int count, int sz, early_memunmap(tbl, sizeof(*tbl)); } + return 0; +} +int __init efi_apply_persistent_mem_reservations(void) +{ if (efi.mem_reserve != EFI_INVALID_TABLE_ADDR) { unsigned long prsv = efi.mem_reserve; diff --git a/drivers/firmware/efi/libstub/arm-stub.c b/drivers/firmware/efi/libstub/arm-stub.c index 30ac0c975f8a..3d36142cf812 100644 --- a/drivers/firmware/efi/libstub/arm-stub.c +++ b/drivers/firmware/efi/libstub/arm-stub.c @@ -75,6 +75,9 @@ void install_memreserve_table(efi_system_table_t *sys_table_arg) efi_guid_t memreserve_table_guid = LINUX_EFI_MEMRESERVE_TABLE_GUID; efi_status_t status; + if (IS_ENABLED(CONFIG_ARM)) + return; + status = efi_call_early(allocate_pool, EFI_LOADER_DATA, sizeof(*rsv), (void **)&rsv); if (status != EFI_SUCCESS) { diff --git a/include/linux/efi.h b/include/linux/efi.h index 845174e113ce..100ce4a4aff6 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -1167,6 +1167,8 @@ static inline bool efi_enabled(int feature) extern void efi_reboot(enum reboot_mode reboot_mode, const char *__unused); extern bool efi_is_table_address(unsigned long phys_addr); + +extern int efi_apply_persistent_mem_reservations(void); #else static inline bool efi_enabled(int feature) { @@ -1185,6 +1187,11 @@ static inline bool efi_is_table_address(unsigned long phys_addr) { return false; } + +static inline int efi_apply_persistent_mem_reservations(void) +{ + return 0; +} #endif extern int efi_status_to_err(efi_status_t status); From 63eb322d89c8505af9b4a3d703e85e42281ebaa0 Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Wed, 14 Nov 2018 09:55:44 -0800 Subject: [PATCH 5/5] efi: Permit calling efi_mem_reserve_persistent() from atomic context Currently, efi_mem_reserve_persistent() may not be called from atomic context, since both the kmalloc() call and the memremap() call may sleep. The kmalloc() call is easy enough to fix, but the memremap() call needs to be moved into an init hook since we cannot control the memory allocation behavior of memremap() at the call site. Signed-off-by: Ard Biesheuvel Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/20181114175544.12860-6-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar --- drivers/firmware/efi/efi.c | 33 ++++++++++++++++++++------------- 1 file changed, 20 insertions(+), 13 deletions(-) diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index 72a4da76d274..fad7c62cfc0e 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -967,37 +967,44 @@ bool efi_is_table_address(unsigned long phys_addr) } static DEFINE_SPINLOCK(efi_mem_reserve_persistent_lock); +static struct linux_efi_memreserve *efi_memreserve_root __ro_after_init; int efi_mem_reserve_persistent(phys_addr_t addr, u64 size) { - struct linux_efi_memreserve *rsv, *parent; + struct linux_efi_memreserve *rsv; - if (efi.mem_reserve == EFI_INVALID_TABLE_ADDR) + if (!efi_memreserve_root) return -ENODEV; - rsv = kmalloc(sizeof(*rsv), GFP_KERNEL); + rsv = kmalloc(sizeof(*rsv), GFP_ATOMIC); if (!rsv) return -ENOMEM; - parent = memremap(efi.mem_reserve, sizeof(*rsv), MEMREMAP_WB); - if (!parent) { - kfree(rsv); - return -ENOMEM; - } - rsv->base = addr; rsv->size = size; spin_lock(&efi_mem_reserve_persistent_lock); - rsv->next = parent->next; - parent->next = __pa(rsv); + rsv->next = efi_memreserve_root->next; + efi_memreserve_root->next = __pa(rsv); spin_unlock(&efi_mem_reserve_persistent_lock); - memunmap(parent); - return 0; } +static int __init efi_memreserve_root_init(void) +{ + if (efi.mem_reserve == EFI_INVALID_TABLE_ADDR) + return -ENODEV; + + efi_memreserve_root = memremap(efi.mem_reserve, + sizeof(*efi_memreserve_root), + MEMREMAP_WB); + if (!efi_memreserve_root) + return -ENOMEM; + return 0; +} +early_initcall(efi_memreserve_root_init); + #ifdef CONFIG_KEXEC static int update_efi_random_seed(struct notifier_block *nb, unsigned long code, void *unused)