This is a note to let you know that I've just added the patch titled
x86/tdx: Prepare for using "INFO" call for a second purpose
to the 6.0-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-tdx-prepare-for-using-info-call-for-a-second-purpose.patch
and it can be found in the queue-6.0 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From a6dd6f39008bb3ef7c73ef0a2acc2a4209555bd8 Mon Sep 17 00:00:00 2001
From: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Date: Fri, 28 Oct 2022 17:12:19 +0300
Subject: x86/tdx: Prepare for using "INFO" call for a second purpose
From: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
commit a6dd6f39008bb3ef7c73ef0a2acc2a4209555bd8 upstream.
The TDG.VP.INFO TDCALL provides the guest with various details about
the TDX system that the guest needs to run. Only one field is currently
used: 'gpa_width' which tells the guest which PTE bits mark pages shared
or private.
A second field is now needed: the guest "TD attributes" to tell if
virtualization exceptions are configured in a way that can harm the guest.
Make the naming and calling convention more generic and discrete from the
mask-centric one.
Thanks to Sathya for the inspiration here, but there's no code, comments
or changelogs left from where he started.
Signed-off-by: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Acked-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Tested-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/x86/coco/tdx/tdx.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
--- a/arch/x86/coco/tdx/tdx.c
+++ b/arch/x86/coco/tdx/tdx.c
@@ -98,7 +98,7 @@ static inline void tdx_module_call(u64 f
panic("TDCALL %lld failed (Buggy TDX module!)\n", fn);
}
-static u64 get_cc_mask(void)
+static void tdx_parse_tdinfo(u64 *cc_mask)
{
struct tdx_module_output out;
unsigned int gpa_width;
@@ -121,7 +121,7 @@ static u64 get_cc_mask(void)
* The highest bit of a guest physical address is the "sharing" bit.
* Set it for shared pages and clear it for private pages.
*/
- return BIT_ULL(gpa_width - 1);
+ *cc_mask = BIT_ULL(gpa_width - 1);
}
/*
@@ -758,7 +758,7 @@ void __init tdx_early_init(void)
setup_force_cpu_cap(X86_FEATURE_TDX_GUEST);
cc_set_vendor(CC_VENDOR_INTEL);
- cc_mask = get_cc_mask();
+ tdx_parse_tdinfo(&cc_mask);
cc_set_mask(cc_mask);
/*
Patches currently in stable-queue which might be from dave.hansen@xxxxxxxxxxxxxxx are
queue-6.0/x86-tdx-panic-on-bad-configs-that-ve-on-private-memory-access.patch
queue-6.0/x86-tdx-prepare-for-using-info-call-for-a-second-purpose.patch
