Commit-ID: aa4ea675528f3fa11e9663e5a32f55a81c34dcac
Gitweb: http://git.kernel.org/tip/aa4ea675528f3fa11e9663e5a32f55a81c34dcac
Author: Andy Lutomirski <l...@kernel.org>
AuthorDate: Wed, 22 Mar 2017 14:32:30 -0700
Committer: Ingo Molnar <mi...@kernel.org>
CommitDate: Thu, 23 Mar 2017 08:25:07 +0100
x86/gdt: Fix setup_fixmap_gdt() to use the correct PA
__pa() cannot be used on percpu pointers because they may be
virtually mapped. Use per_cpu_ptr_to_phys() instead.
This fixes a boot crash on a some 32-bit configurations. I assume
this is related to which allocation strategy is chosen by the percpu
core.
Signed-off-by: Andy Lutomirski <l...@kernel.org>
Cc: Boris Ostrovsky <boris.ostrov...@oracle.com>
Cc: Borislav Petkov <b...@alien8.de>
Cc: Brian Gerst <brge...@gmail.com>
Cc: Denys Vlasenko <dvlas...@redhat.com>
Cc: H. Peter Anvin <h...@zytor.com>
Cc: Josh Poimboeuf <jpoim...@redhat.com>
Cc: Juergen Gross <jgr...@suse.com>
Cc: Linus Torvalds <torva...@linux-foundation.org>
Cc: Peter Zijlstra <pet...@infradead.org>
Cc: Thomas Garnier <thgar...@google.com>
Cc: Thomas Gleixner <t...@linutronix.de>
Fixes: 69218e47994d x86: ("Remap GDT tables in the fixmap section")
Link:
http://lkml.kernel.org/r/22e0069c29fba31998f193201e359eebfdac4960.1490218061.git.l...@kernel.org
Signed-off-by: Ingo Molnar <mi...@kernel.org>
---
arch/x86/include/asm/desc.h | 6 ++++++
arch/x86/kernel/cpu/common.c | 4 ++--
2 files changed, 8 insertions(+), 2 deletions(-)
diff --git a/arch/x86/include/asm/desc.h b/arch/x86/include/asm/desc.h
index ec05f9c..bde1169 100644
--- a/arch/x86/include/asm/desc.h
+++ b/arch/x86/include/asm/desc.h
@@ -98,6 +98,12 @@ static inline unsigned long get_current_gdt_ro_vaddr(void)
return (unsigned long)get_current_gdt_ro();
}
+/* Provide the physical address of the GDT page. */
+static inline phys_addr_t get_cpu_gdt_paddr(unsigned int cpu)
+{
+ return per_cpu_ptr_to_phys(get_cpu_gdt_rw(cpu));
+}
+
#ifdef CONFIG_X86_64
static inline void pack_gate(gate_desc *gate, unsigned type, unsigned long
func,
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index f8e22db..f6e20e2 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -461,8 +461,8 @@ pgprot_t pg_fixmap_gdt_flags = PAGE_KERNEL;
/* Setup the fixmap mapping only once per-processor */
static inline void setup_fixmap_gdt(int cpu)
{
- __set_fixmap(get_cpu_gdt_ro_index(cpu),
- __pa(get_cpu_gdt_rw(cpu)), pg_fixmap_gdt_flags);
+ __set_fixmap(get_cpu_gdt_ro_index(cpu), get_cpu_gdt_paddr(cpu),
+ pg_fixmap_gdt_flags);
}
/* Load the original GDT from the per-cpu structure */
