This is a note to let you know that I've just added the patch titled
x86/xen/efi: Initialize only the EFI struct members used by Xen
to the 4.12-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
x86-xen-efi-initialize-only-the-efi-struct-members-used-by-xen.patch
and it can be found in the queue-4.12 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 6c64447ec58b0bac612732303f7ab04562124587 Mon Sep 17 00:00:00 2001
From: Daniel Kiper <daniel.kiper@xxxxxxxxxx>
Date: Thu, 22 Jun 2017 12:51:37 +0200
Subject: x86/xen/efi: Initialize only the EFI struct members used by Xen
From: Daniel Kiper <daniel.kiper@xxxxxxxxxx>
commit 6c64447ec58b0bac612732303f7ab04562124587 upstream.
The current approach, which is the wholesale efi struct initialization from
a 'efi_xen' local template is not robust. Usually if new member is defined
then it is properly initialized in drivers/firmware/efi/efi.c, but not in
arch/x86/xen/efi.c.
The effect is that the Xen initialization clears any fields the generic code
might have set and the Xen code does not know about yet.
I saw this happen a few times, so let's initialize only the EFI struct members
used by Xen and maintain no local duplicate, to avoid such issues in the future.
Signed-off-by: Daniel Kiper <daniel.kiper@xxxxxxxxxx>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@xxxxxxxxxx>
Acked-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: andrew.cooper3@xxxxxxxxxx
Cc: jgross@xxxxxxxx
Cc: linux-efi@xxxxxxxxxxxxxxx
Cc: matt@xxxxxxxxxxxxxxxxxxx
Cc: xen-devel@xxxxxxxxxxxxxxxxxxxx
Link: http://lkml.kernel.org/r/1498128697-12943-3-git-send-email-daniel.kiper@xxxxxxxxxx
[ Clarified the changelog. ]
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/x86/xen/efi.c | 45 ++++++++++++---------------------------------
1 file changed, 12 insertions(+), 33 deletions(-)
--- a/arch/x86/xen/efi.c
+++ b/arch/x86/xen/efi.c
@@ -54,38 +54,6 @@ static efi_system_table_t efi_systab_xen
.tables = EFI_INVALID_TABLE_ADDR /* Initialized later. */
};
-static const struct efi efi_xen __initconst = {
- .systab = NULL, /* Initialized later. */
- .runtime_version = 0, /* Initialized later. */
- .mps = EFI_INVALID_TABLE_ADDR,
- .acpi = EFI_INVALID_TABLE_ADDR,
- .acpi20 = EFI_INVALID_TABLE_ADDR,
- .smbios = EFI_INVALID_TABLE_ADDR,
- .smbios3 = 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,
- .fw_vendor = EFI_INVALID_TABLE_ADDR,
- .runtime = EFI_INVALID_TABLE_ADDR,
- .config_table = EFI_INVALID_TABLE_ADDR,
- .get_time = xen_efi_get_time,
- .set_time = xen_efi_set_time,
- .get_wakeup_time = xen_efi_get_wakeup_time,
- .set_wakeup_time = xen_efi_set_wakeup_time,
- .get_variable = xen_efi_get_variable,
- .get_next_variable = xen_efi_get_next_variable,
- .set_variable = xen_efi_set_variable,
- .query_variable_info = xen_efi_query_variable_info,
- .update_capsule = xen_efi_update_capsule,
- .query_capsule_caps = xen_efi_query_capsule_caps,
- .get_next_high_mono_count = xen_efi_get_next_high_mono_count,
- .reset_system = xen_efi_reset_system,
- .set_virtual_address_map = NULL, /* Not used under Xen. */
- .flags = 0 /* Initialized later. */
-};
-
static efi_system_table_t __init *xen_efi_probe(void)
{
struct xen_platform_op op = {
@@ -102,7 +70,18 @@ static efi_system_table_t __init *xen_ef
/* Here we know that Xen runs on EFI platform. */
- efi = efi_xen;
+ efi.get_time = xen_efi_get_time;
+ efi.set_time = xen_efi_set_time;
+ efi.get_wakeup_time = xen_efi_get_wakeup_time;
+ efi.set_wakeup_time = xen_efi_set_wakeup_time;
+ efi.get_variable = xen_efi_get_variable;
+ efi.get_next_variable = xen_efi_get_next_variable;
+ efi.set_variable = xen_efi_set_variable;
+ efi.query_variable_info = xen_efi_query_variable_info;
+ efi.update_capsule = xen_efi_update_capsule;
+ efi.query_capsule_caps = xen_efi_query_capsule_caps;
+ efi.get_next_high_mono_count = xen_efi_get_next_high_mono_count;
+ efi.reset_system = xen_efi_reset_system;
efi_systab_xen.tables = info->cfg.addr;
efi_systab_xen.nr_tables = info->cfg.nent;
Patches currently in stable-queue which might be from daniel.kiper@xxxxxxxxxx are
queue-4.12/efi-process-the-memattr-table-only-if-efi_memmap-is-enabled.patch
queue-4.12/x86-xen-efi-initialize-only-the-efi-struct-members-used-by-xen.patch