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authorLinus Torvalds <torvalds@linux-foundation.org>2018-12-27 00:38:38 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2018-12-27 00:38:38 +0300
commit684019dd1f0092b4ffce4958c84aff0891deac83 (patch)
tree65977a5481527c26fe4a027badb9825b71ab9d35 /arch
parent792bf4d871dea8b69be2aaabdd320d7c6ed15985 (diff)
parent1debf0958fa27b7c469dbf22754929ec59a7c0e7 (diff)
downloadlinux-684019dd1f0092b4ffce4958c84aff0891deac83.tar.xz
Merge branch 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull EFI updates from Ingo Molnar: "The main changes in this cycle were: - Allocate the E820 buffer before doing the GetMemoryMap/ExitBootServices dance so we don't run out of space - Clear EFI boot services mappings when freeing the memory - Harden efivars against callers that invoke it on non-EFI boots - Reduce the number of memblock reservations resulting from extensive use of the new efi_mem_reserve_persistent() API - Other assorted fixes and cleanups" * 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/efi: Don't unmap EFI boot services code/data regions for EFI_OLD_MEMMAP and EFI_MIXED_MODE efi: Reduce the amount of memblock reservations for persistent allocations efi: Permit multiple entries in persistent memreserve data structure efi/libstub: Disable some warnings for x86{,_64} x86/efi: Move efi_<reserve/free>_boot_services() to arch/x86 x86/efi: Unmap EFI boot services code/data regions from efi_pgd x86/mm/pageattr: Introduce helper function to unmap EFI boot services efi/fdt: Simplify the get_fdt() flow efi/fdt: Indentation fix firmware/efi: Add NULL pointer checks in efivars API functions
Diffstat (limited to 'arch')
-rw-r--r--arch/x86/include/asm/efi.h2
-rw-r--r--arch/x86/include/asm/pgtable_types.h8
-rw-r--r--arch/x86/mm/pageattr.c40
-rw-r--r--arch/x86/platform/efi/efi.c2
-rw-r--r--arch/x86/platform/efi/quirks.c41
5 files changed, 89 insertions, 4 deletions
diff --git a/arch/x86/include/asm/efi.h b/arch/x86/include/asm/efi.h
index eea40d52ca78..d1e64ac80b9c 100644
--- a/arch/x86/include/asm/efi.h
+++ b/arch/x86/include/asm/efi.h
@@ -141,6 +141,8 @@ extern int __init efi_reuse_config(u64 tables, int nr_tables);
extern void efi_delete_dummy_variable(void);
extern void efi_switch_mm(struct mm_struct *mm);
extern void efi_recover_from_page_fault(unsigned long phys_addr);
+extern void efi_free_boot_services(void);
+extern void efi_reserve_boot_services(void);
struct efi_setup_data {
u64 fw_vendor;
diff --git a/arch/x86/include/asm/pgtable_types.h b/arch/x86/include/asm/pgtable_types.h
index 106b7d0e2dae..d6ff0bbdb394 100644
--- a/arch/x86/include/asm/pgtable_types.h
+++ b/arch/x86/include/asm/pgtable_types.h
@@ -564,8 +564,12 @@ extern pte_t *lookup_address_in_pgd(pgd_t *pgd, unsigned long address,
unsigned int *level);
extern pmd_t *lookup_pmd_address(unsigned long address);
extern phys_addr_t slow_virt_to_phys(void *__address);
-extern int kernel_map_pages_in_pgd(pgd_t *pgd, u64 pfn, unsigned long address,
- unsigned numpages, unsigned long page_flags);
+extern int __init kernel_map_pages_in_pgd(pgd_t *pgd, u64 pfn,
+ unsigned long address,
+ unsigned numpages,
+ unsigned long page_flags);
+extern int __init kernel_unmap_pages_in_pgd(pgd_t *pgd, unsigned long address,
+ unsigned long numpages);
#endif /* !__ASSEMBLY__ */
#endif /* _ASM_X86_PGTABLE_DEFS_H */
diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c
index a1bcde35db4c..61bc7d1800d7 100644
--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pageattr.c
@@ -2346,8 +2346,8 @@ bool kernel_page_present(struct page *page)
#endif /* CONFIG_DEBUG_PAGEALLOC */
-int kernel_map_pages_in_pgd(pgd_t *pgd, u64 pfn, unsigned long address,
- unsigned numpages, unsigned long page_flags)
+int __init kernel_map_pages_in_pgd(pgd_t *pgd, u64 pfn, unsigned long address,
+ unsigned numpages, unsigned long page_flags)
{
int retval = -EINVAL;
@@ -2361,6 +2361,8 @@ int kernel_map_pages_in_pgd(pgd_t *pgd, u64 pfn, unsigned long address,
.flags = 0,
};
+ WARN_ONCE(num_online_cpus() > 1, "Don't call after initializing SMP");
+
if (!(__supported_pte_mask & _PAGE_NX))
goto out;
@@ -2383,6 +2385,40 @@ out:
}
/*
+ * __flush_tlb_all() flushes mappings only on current CPU and hence this
+ * function shouldn't be used in an SMP environment. Presently, it's used only
+ * during boot (way before smp_init()) by EFI subsystem and hence is ok.
+ */
+int __init kernel_unmap_pages_in_pgd(pgd_t *pgd, unsigned long address,
+ unsigned long numpages)
+{
+ int retval;
+
+ /*
+ * The typical sequence for unmapping is to find a pte through
+ * lookup_address_in_pgd() (ideally, it should never return NULL because
+ * the address is already mapped) and change it's protections. As pfn is
+ * the *target* of a mapping, it's not useful while unmapping.
+ */
+ struct cpa_data cpa = {
+ .vaddr = &address,
+ .pfn = 0,
+ .pgd = pgd,
+ .numpages = numpages,
+ .mask_set = __pgprot(0),
+ .mask_clr = __pgprot(_PAGE_PRESENT | _PAGE_RW),
+ .flags = 0,
+ };
+
+ WARN_ONCE(num_online_cpus() > 1, "Don't call after initializing SMP");
+
+ retval = __change_page_attr_set_clr(&cpa, 0);
+ __flush_tlb_all();
+
+ return retval;
+}
+
+/*
* The testcases use internal knowledge of the implementation that shouldn't
* be exposed to the rest of the kernel. Include these directly here.
*/
diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
index 7ae939e353cd..e1cb01a22fa8 100644
--- a/arch/x86/platform/efi/efi.c
+++ b/arch/x86/platform/efi/efi.c
@@ -993,6 +993,8 @@ static void __init __efi_enter_virtual_mode(void)
panic("EFI call to SetVirtualAddressMap() failed!");
}
+ efi_free_boot_services();
+
/*
* Now that EFI is in virtual mode, update the function
* pointers in the runtime service table to the new virtual addresses.
diff --git a/arch/x86/platform/efi/quirks.c b/arch/x86/platform/efi/quirks.c
index 95e77a667ba5..17456a1d3f04 100644
--- a/arch/x86/platform/efi/quirks.c
+++ b/arch/x86/platform/efi/quirks.c
@@ -369,6 +369,40 @@ void __init efi_reserve_boot_services(void)
}
}
+/*
+ * Apart from having VA mappings for EFI boot services code/data regions,
+ * (duplicate) 1:1 mappings were also created as a quirk for buggy firmware. So,
+ * unmap both 1:1 and VA mappings.
+ */
+static void __init efi_unmap_pages(efi_memory_desc_t *md)
+{
+ pgd_t *pgd = efi_mm.pgd;
+ u64 pa = md->phys_addr;
+ u64 va = md->virt_addr;
+
+ /*
+ * To Do: Remove this check after adding functionality to unmap EFI boot
+ * services code/data regions from direct mapping area because
+ * "efi=old_map" maps EFI regions in swapper_pg_dir.
+ */
+ if (efi_enabled(EFI_OLD_MEMMAP))
+ return;
+
+ /*
+ * EFI mixed mode has all RAM mapped to access arguments while making
+ * EFI runtime calls, hence don't unmap EFI boot services code/data
+ * regions.
+ */
+ if (!efi_is_native())
+ return;
+
+ if (kernel_unmap_pages_in_pgd(pgd, pa, md->num_pages))
+ pr_err("Failed to unmap 1:1 mapping for 0x%llx\n", pa);
+
+ if (kernel_unmap_pages_in_pgd(pgd, va, md->num_pages))
+ pr_err("Failed to unmap VA mapping for 0x%llx\n", va);
+}
+
void __init efi_free_boot_services(void)
{
phys_addr_t new_phys, new_size;
@@ -394,6 +428,13 @@ void __init efi_free_boot_services(void)
}
/*
+ * Before calling set_virtual_address_map(), EFI boot services
+ * code/data regions were mapped as a quirk for buggy firmware.
+ * Unmap them from efi_pgd before freeing them up.
+ */
+ efi_unmap_pages(md);
+
+ /*
* Nasty quirk: if all sub-1MB memory is used for boot
* services, we can get here without having allocated the
* real mode trampoline. It's too late to hand boot services