Merge branch 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull EFI fixes from Ingo Molnar:
 "Three EFI fixes:

   - Fix a slow-boot-scrolling regression but making sure we use WC for
     EFI earlycon framebuffer mappings on x86

   - Fix a mixed EFI mode boot crash

   - Disable paging explicitly before entering startup_32() in mixed
     mode bootup"

* 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/efistub: Disable paging at mixed mode entry
  efi/libstub/random: Initialize pointer variables to zero for mixed mode
  efi/earlycon: Fix write-combine mapping on x86
This commit is contained in:
Linus Torvalds 2020-01-18 12:50:14 -08:00
commit e2f73d1e52
3 changed files with 15 additions and 12 deletions

View File

@ -244,6 +244,11 @@ SYM_FUNC_START(efi32_stub_entry)
leal efi32_config(%ebp), %eax
movl %eax, efi_config(%ebp)
/* Disable paging */
movl %cr0, %eax
btrl $X86_CR0_PG_BIT, %eax
movl %eax, %cr0
jmp startup_32
SYM_FUNC_END(efi32_stub_entry)
#endif

View File

@ -17,7 +17,7 @@ static const struct console *earlycon_console __initdata;
static const struct font_desc *font;
static u32 efi_x, efi_y;
static u64 fb_base;
static pgprot_t fb_prot;
static bool fb_wb;
static void *efi_fb;
/*
@ -33,10 +33,8 @@ static int __init efi_earlycon_remap_fb(void)
if (!earlycon_console || !(earlycon_console->flags & CON_ENABLED))
return 0;
if (pgprot_val(fb_prot) == pgprot_val(PAGE_KERNEL))
efi_fb = memremap(fb_base, screen_info.lfb_size, MEMREMAP_WB);
else
efi_fb = memremap(fb_base, screen_info.lfb_size, MEMREMAP_WC);
efi_fb = memremap(fb_base, screen_info.lfb_size,
fb_wb ? MEMREMAP_WB : MEMREMAP_WC);
return efi_fb ? 0 : -ENOMEM;
}
@ -53,9 +51,12 @@ late_initcall(efi_earlycon_unmap_fb);
static __ref void *efi_earlycon_map(unsigned long start, unsigned long len)
{
pgprot_t fb_prot;
if (efi_fb)
return efi_fb + start;
fb_prot = fb_wb ? PAGE_KERNEL : pgprot_writecombine(PAGE_KERNEL);
return early_memremap_prot(fb_base + start, len, pgprot_val(fb_prot));
}
@ -215,10 +216,7 @@ static int __init efi_earlycon_setup(struct earlycon_device *device,
if (screen_info.capabilities & VIDEO_CAPABILITY_64BIT_BASE)
fb_base |= (u64)screen_info.ext_lfb_base << 32;
if (opt && !strcmp(opt, "ram"))
fb_prot = PAGE_KERNEL;
else
fb_prot = pgprot_writecombine(PAGE_KERNEL);
fb_wb = opt && !strcmp(opt, "ram");
si = &screen_info;
xres = si->lfb_width;

View File

@ -33,7 +33,7 @@ efi_status_t efi_get_random_bytes(efi_system_table_t *sys_table_arg,
{
efi_guid_t rng_proto = EFI_RNG_PROTOCOL_GUID;
efi_status_t status;
struct efi_rng_protocol *rng;
struct efi_rng_protocol *rng = NULL;
status = efi_call_early(locate_protocol, &rng_proto, NULL,
(void **)&rng);
@ -162,8 +162,8 @@ efi_status_t efi_random_get_seed(efi_system_table_t *sys_table_arg)
efi_guid_t rng_proto = EFI_RNG_PROTOCOL_GUID;
efi_guid_t rng_algo_raw = EFI_RNG_ALGORITHM_RAW;
efi_guid_t rng_table_guid = LINUX_EFI_RANDOM_SEED_TABLE_GUID;
struct efi_rng_protocol *rng;
struct linux_efi_random_seed *seed;
struct efi_rng_protocol *rng = NULL;
struct linux_efi_random_seed *seed = NULL;
efi_status_t status;
status = efi_call_early(locate_protocol, &rng_proto, NULL,