From 9b89183b97f3d906a8df1050707d48a74e35caed Mon Sep 17 00:00:00 2001 From: Eugeniu Rosca Date: Sat, 14 Jul 2018 22:53:30 +0200 Subject: [PATCH] efi: Fix truncation of constant value Starting with commit 867a6ac86dd8 ("efi: Add start-up library code"), sparse constantly complains about truncated constant value in efi.h: include/efi.h:176:35: warning: cast truncates bits from constant value (8000000000000000 becomes 0) This can get quite noisy, preventing real issues to be noticed: $ make defconfig *** Default configuration is based on 'sandbox_defconfig' $ make C=2 -j12 2>&1 | grep truncates | wc -l 441 After the patch is applied: $ make C=2 -j12 2>&1 | grep truncates | wc -l 0 $ sparse --version v0.5.2 Following the suggestion of Heinrich Schuchardt, instead of only fixing the root-cause, I replaced the whole enum of _SHIFT values by ULL defines. This matches both the UEFI 2.7 spec and the Linux kernel implementation. Some ELF size comparison before and after the patch (gcc 7.3.0): efi-x86_payload64_defconfig: text data bss dec hex filename 407174 29432 278676 715282 aea12 u-boot.old 407152 29464 278676 715292 aea1c u-boot.new -22 +32 0 +10 efi-x86_payload32_defconfig: text data bss dec hex filename 447075 30308 280076 757459 b8ed3 u-boot.old 447053 30340 280076 757469 b8edd u-boot.new -22 +32 0 +10 Fixes: 867a6ac86dd8 ("efi: Add start-up library code") Suggested-by: Heinrich Schuchardt Signed-off-by: Eugeniu Rosca Reviewed-by: Heinrich Schuchardt Reviewed-by: Heinrich Schuchardt Signed-off-by: Alexander Graf --- cmd/efi.c | 22 +++++++++++----------- include/efi.h | 24 ++++++++++-------------- lib/efi_loader/efi_memory.c | 7 +++---- 3 files changed, 24 insertions(+), 29 deletions(-) diff --git a/cmd/efi.c b/cmd/efi.c index 6c1eb88..92a565f 100644 --- a/cmd/efi.c +++ b/cmd/efi.c @@ -28,18 +28,18 @@ static const char *const type_name[] = { }; static struct attr_info { - int shift; + u64 val; const char *name; } mem_attr[] = { - { EFI_MEMORY_UC_SHIFT, "uncached" }, - { EFI_MEMORY_WC_SHIFT, "write-coalescing" }, - { EFI_MEMORY_WT_SHIFT, "write-through" }, - { EFI_MEMORY_WB_SHIFT, "write-back" }, - { EFI_MEMORY_UCE_SHIFT, "uncached & exported" }, - { EFI_MEMORY_WP_SHIFT, "write-protect" }, - { EFI_MEMORY_RP_SHIFT, "read-protect" }, - { EFI_MEMORY_XP_SHIFT, "execute-protect" }, - { EFI_MEMORY_RUNTIME_SHIFT, "needs runtime mapping" } + { EFI_MEMORY_UC, "uncached" }, + { EFI_MEMORY_WC, "write-coalescing" }, + { EFI_MEMORY_WT, "write-through" }, + { EFI_MEMORY_WB, "write-back" }, + { EFI_MEMORY_UCE, "uncached & exported" }, + { EFI_MEMORY_WP, "write-protect" }, + { EFI_MEMORY_RP, "read-protect" }, + { EFI_MEMORY_XP, "execute-protect" }, + { EFI_MEMORY_RUNTIME, "needs runtime mapping" } }; /* Maximum different attribute values we can track */ @@ -173,7 +173,7 @@ static void efi_print_mem_table(struct efi_entry_memmap *map, printf("%c%llx: ", attr & EFI_MEMORY_RUNTIME ? 'r' : ' ', attr & ~EFI_MEMORY_RUNTIME); for (j = 0, first = true; j < ARRAY_SIZE(mem_attr); j++) { - if (attr & (1ULL << mem_attr[j].shift)) { + if (attr & mem_attr[j].val) { if (first) first = false; else diff --git a/include/efi.h b/include/efi.h index 41530a7..cfdccd7 100644 --- a/include/efi.h +++ b/include/efi.h @@ -170,20 +170,16 @@ enum efi_mem_type { }; /* Attribute values */ -enum { - EFI_MEMORY_UC_SHIFT = 0, /* uncached */ - EFI_MEMORY_WC_SHIFT = 1, /* write-coalescing */ - EFI_MEMORY_WT_SHIFT = 2, /* write-through */ - EFI_MEMORY_WB_SHIFT = 3, /* write-back */ - EFI_MEMORY_UCE_SHIFT = 4, /* uncached, exported */ - EFI_MEMORY_WP_SHIFT = 12, /* write-protect */ - EFI_MEMORY_RP_SHIFT = 13, /* read-protect */ - EFI_MEMORY_XP_SHIFT = 14, /* execute-protect */ - EFI_MEMORY_RUNTIME_SHIFT = 63, /* range requires runtime mapping */ - - EFI_MEMORY_RUNTIME = 1ULL << EFI_MEMORY_RUNTIME_SHIFT, - EFI_MEM_DESC_VERSION = 1, -}; +#define EFI_MEMORY_UC ((u64)0x0000000000000001ULL) /* uncached */ +#define EFI_MEMORY_WC ((u64)0x0000000000000002ULL) /* write-coalescing */ +#define EFI_MEMORY_WT ((u64)0x0000000000000004ULL) /* write-through */ +#define EFI_MEMORY_WB ((u64)0x0000000000000008ULL) /* write-back */ +#define EFI_MEMORY_UCE ((u64)0x0000000000000010ULL) /* uncached, exported */ +#define EFI_MEMORY_WP ((u64)0x0000000000001000ULL) /* write-protect */ +#define EFI_MEMORY_RP ((u64)0x0000000000002000ULL) /* read-protect */ +#define EFI_MEMORY_XP ((u64)0x0000000000004000ULL) /* execute-protect */ +#define EFI_MEMORY_RUNTIME ((u64)0x8000000000000000ULL) /* range requires runtime mapping */ +#define EFI_MEM_DESC_VERSION 1 #define EFI_PAGE_SHIFT 12 #define EFI_PAGE_SIZE (1UL << EFI_PAGE_SHIFT) diff --git a/lib/efi_loader/efi_memory.c b/lib/efi_loader/efi_memory.c index 3ee1079..e2b40aa 100644 --- a/lib/efi_loader/efi_memory.c +++ b/lib/efi_loader/efi_memory.c @@ -178,14 +178,13 @@ uint64_t efi_add_memory_map(uint64_t start, uint64_t pages, int memory_type, switch (memory_type) { case EFI_RUNTIME_SERVICES_CODE: case EFI_RUNTIME_SERVICES_DATA: - newlist->desc.attribute = (1 << EFI_MEMORY_WB_SHIFT) | - (1ULL << EFI_MEMORY_RUNTIME_SHIFT); + newlist->desc.attribute = EFI_MEMORY_WB | EFI_MEMORY_RUNTIME; break; case EFI_MMAP_IO: - newlist->desc.attribute = 1ULL << EFI_MEMORY_RUNTIME_SHIFT; + newlist->desc.attribute = EFI_MEMORY_RUNTIME; break; default: - newlist->desc.attribute = 1 << EFI_MEMORY_WB_SHIFT; + newlist->desc.attribute = EFI_MEMORY_WB; break; } -- 2.7.4