[PATCH, resend] x86/EFI: properly pre-initialize table pointers

[PATCH, resend] x86/EFI: properly pre-initialize table pointers

[Jan Beulich]

Consumers of the table pointers in struct efi check for
EFI_INVALID_TABLE_ADDR to determine validity, hence these pointers
should all be pre-initialized to this value (rather than zero).

Noticed by the discrepancy between efivars' systab sysfs entry showing
all tables (and their pointers) despite the code intending to only
display the valid ones. No other bad effects known, but having the
various table parsing routines bogusly access physical address zero is
certainly not very desirable (even though they're unlikely to find
anything useful there).

Signed-off-by: Jan Beulich <jbeulich@novell.com>

---
 arch/x86/platform/efi/efi.c |   12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

--- 3.0-rc6/arch/x86/platform/efi/efi.c
+++ 3.0-rc6-x86-EFI/arch/x86/platform/efi/efi.c
@@ -51,7 +51,17 @@
 int efi_enabled;
 EXPORT_SYMBOL(efi_enabled);
 
-struct efi efi;
+struct efi __read_mostly efi = {
+	.mps        = EFI_INVALID_TABLE_ADDR,
+	.acpi       = EFI_INVALID_TABLE_ADDR,
+	.acpi20     = EFI_INVALID_TABLE_ADDR,
+	.smbios     = EFI_INVALID_TABLE_ADDR,
+	.sal_systab = EFI_INVALID_TABLE_ADDR,
+	.boot_info  = EFI_INVALID_TABLE_ADDR,
+	.hcdp       = EFI_INVALID_TABLE_ADDR,
+	.uga        = EFI_INVALID_TABLE_ADDR,
+	.uv_systab  = EFI_INVALID_TABLE_ADDR,
+};
 EXPORT_SYMBOL(efi);
 
 struct efi_memory_map memmap;

[tip:x86/efi] x86, efi: Properly pre-initialize table pointers

[tip-bot for Jan Beulich]

Commit-ID:  d80603c9d876efafd8b07469c891076de470e323
Gitweb:     http://git.kernel.org/tip/d80603c9d876efafd8b07469c891076de470e323
Author:     Jan Beulich <JBeulich@novell.com>
AuthorDate: Tue, 5 Jul 2011 12:22:18 +0100
Committer:  Ingo Molnar <mingo@elte.hu>
CommitDate: Tue, 5 Jul 2011 13:40:34 +0200

x86, efi: Properly pre-initialize table pointers

Consumers of the table pointers in struct efi check for
EFI_INVALID_TABLE_ADDR to determine validity, hence these
pointers should all be pre-initialized to this value (rather
than zero).

Noticed by the discrepancy between efivars' systab sysfs entry
showing all tables (and their pointers) despite the code
intending to only display the valid ones. No other bad effects
known, but having the various table parsing routines bogusly
access physical address zero is certainly not very desirable
(even though they're unlikely to find anything useful there).

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Link: http://lkml.kernel.org/r/4E13100A020000780004C256@nat28.tlf.novell.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 arch/x86/platform/efi/efi.c |   12 +++++++++++-
 1 files changed, 11 insertions(+), 1 deletions(-)

diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
index a0e4244..11e766d 100644
--- a/arch/x86/platform/efi/efi.c
+++ b/arch/x86/platform/efi/efi.c
@@ -51,7 +51,17 @@
 int efi_enabled;
 EXPORT_SYMBOL(efi_enabled);
 
-struct efi efi;
+struct efi __read_mostly efi = {
+	.mps        = EFI_INVALID_TABLE_ADDR,
+	.acpi       = EFI_INVALID_TABLE_ADDR,
+	.acpi20     = EFI_INVALID_TABLE_ADDR,
+	.smbios     = EFI_INVALID_TABLE_ADDR,
+	.sal_systab = EFI_INVALID_TABLE_ADDR,
+	.boot_info  = EFI_INVALID_TABLE_ADDR,
+	.hcdp       = EFI_INVALID_TABLE_ADDR,
+	.uga        = EFI_INVALID_TABLE_ADDR,
+	.uv_systab  = EFI_INVALID_TABLE_ADDR,
+};
 EXPORT_SYMBOL(efi);
 
 struct efi_memory_map memmap;