Linus,
Please pull the latest x86/mm git tree from:
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git x86-mm-2020-10-12
# HEAD: 7a27ef5e83089090f3a4073a9157c862ef00acfc x86/mm/64: Update comment
in preallocate_vmalloc_pages()
Do not sync vmalloc/ioremap mappings on x86-64 kernels.
Hopefully now without the bugs!
Thanks,
Ingo
------------------>
Joerg Roedel (2):
x86/mm/64: Do not sync vmalloc/ioremap mappings
x86/mm/64: Update comment in preallocate_vmalloc_pages()
arch/x86/include/asm/pgtable_64_types.h | 2 --
arch/x86/mm/init_64.c | 20 ++++++++++----------
2 files changed, 10 insertions(+), 12 deletions(-)
diff --git a/arch/x86/include/asm/pgtable_64_types.h
b/arch/x86/include/asm/pgtable_64_types.h
index 8f63efb2a2cc..52e5f5f2240d 100644
--- a/arch/x86/include/asm/pgtable_64_types.h
+++ b/arch/x86/include/asm/pgtable_64_types.h
@@ -159,6 +159,4 @@ extern unsigned int ptrs_per_p4d;
#define PGD_KERNEL_START ((PAGE_SIZE / 2) / sizeof(pgd_t))
-#define ARCH_PAGE_TABLE_SYNC_MASK (pgtable_l5_enabled() ?
PGTBL_PGD_MODIFIED : PGTBL_P4D_MODIFIED)
-
#endif /* _ASM_X86_PGTABLE_64_DEFS_H */
diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index a4ac13cc3fdc..b5a3fa4033d3 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -217,11 +217,6 @@ static void sync_global_pgds(unsigned long start, unsigned
long end)
sync_global_pgds_l4(start, end);
}
-void arch_sync_kernel_mappings(unsigned long start, unsigned long end)
-{
- sync_global_pgds(start, end);
-}
-
/*
* NOTE: This function is marked __ref because it calls __init function
* (alloc_bootmem_pages). It's safe to do it ONLY when after_bootmem == 0.
@@ -1257,14 +1252,19 @@ static void __init preallocate_vmalloc_pages(void)
if (!p4d)
goto failed;
- /*
- * With 5-level paging the P4D level is not folded. So the PGDs
- * are now populated and there is no need to walk down to the
- * PUD level.
- */
if (pgtable_l5_enabled())
continue;
+ /*
+ * The goal here is to allocate all possibly required
+ * hardware page tables pointed to by the top hardware
+ * level.
+ *
+ * On 4-level systems, the P4D layer is folded away and
+ * the above code does no preallocation. Below, go down
+ * to the pud _software_ level to ensure the second
+ * hardware level is allocated on 4-level systems too.
+ */
lvl = "pud";
pud = pud_alloc(&init_mm, p4d, addr);
if (!pud)
