Commit-ID: caef78b6cdeddf4ad364f95910bba6b43b8eb9bf
Gitweb: http://git.kernel.org/tip/caef78b6cdeddf4ad364f95910bba6b43b8eb9bf
Author: Alex Thorlton <[email protected]>
AuthorDate: Wed, 19 Oct 2016 20:48:51 -0500
Committer: Ingo Molnar <[email protected]>
CommitDate: Thu, 20 Oct 2016 08:47:58 +0200
x86/platform/UV: Fix support for EFI_OLD_MEMMAP after BIOS callback updates
Some time ago, we brought our UV BIOS callback code up to speed with the
new EFI memory mapping scheme, in commit:
d1be84a232e3 ("x86/uv: Update uv_bios_call() to use
efi_call_virt_pointer()")
By leveraging some changes that I made to a few of the EFI runtime
callback mechanisms, in commit:
80e75596079f ("efi: Convert efi_call_virt() to efi_call_virt_pointer()")
This got everything running smoothly on UV, with the new EFI mapping
code. However, this left one, small loose end, in that EFI_OLD_MEMMAP
(a.k.a. efi=old_map) will no longer work on UV, on kernels that include
the aforementioned changes.
At the time this was not a major issue (in fact, it still really isn't),
but there's no reason that EFI_OLD_MEMMAP *shouldn't* work on our
systems. This commit adds a check into uv_bios_call(), to see if we have
the EFI_OLD_MEMMAP bit set in efi.flags. If it is set, we fall back to
using our old callback method, which uses efi_call() directly on the __va()
of our function pointer.
Signed-off-by: Alex Thorlton <[email protected]>
Acked-by: Matt Fleming <[email protected]>
Cc: <[email protected]> # v4.7 and later
Cc: Andy Lutomirski <[email protected]>
Cc: Ard Biesheuvel <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Brian Gerst <[email protected]>
Cc: Denys Vlasenko <[email protected]>
Cc: Dimitri Sivanich <[email protected]>
Cc: H. Peter Anvin <[email protected]>
Cc: Josh Poimboeuf <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Masahiro Yamada <[email protected]>
Cc: Mike Travis <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Russ Anderson <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Link:
http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
---
arch/x86/platform/uv/bios_uv.c | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)
diff --git a/arch/x86/platform/uv/bios_uv.c b/arch/x86/platform/uv/bios_uv.c
index b4d5e95..4a6a5a2 100644
--- a/arch/x86/platform/uv/bios_uv.c
+++ b/arch/x86/platform/uv/bios_uv.c
@@ -40,7 +40,15 @@ s64 uv_bios_call(enum uv_bios_cmd which, u64 a1, u64 a2, u64
a3, u64 a4, u64 a5)
*/
return BIOS_STATUS_UNIMPLEMENTED;
- ret = efi_call_virt_pointer(tab, function, (u64)which, a1, a2, a3, a4,
a5);
+ /*
+ * If EFI_OLD_MEMMAP is set, we need to fall back to using our old EFI
+ * callback method, which uses efi_call() directly, with the kernel
page tables:
+ */
+ if (unlikely(test_bit(EFI_OLD_MEMMAP, &efi.flags)))
+ ret = efi_call((void *)__va(tab->function), (u64)which, a1, a2,
a3, a4, a5);
+ else
+ ret = efi_call_virt_pointer(tab, function, (u64)which, a1, a2,
a3, a4, a5);
+
return ret;
}
EXPORT_SYMBOL_GPL(uv_bios_call);
