6.6-stable review patch. If anyone has any objections, please let me know.
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From: Jason Andryuk jason.andryuk@amd.com
[ Upstream commit b464b461d27d564125db760938643374864c1b1f ]
phys_base needs to be set for __pa() to work in xen_pvh_init() when finding the hypercall page. Set it before calling into xen_prepare_pvh(), which calls xen_pvh_init(). Clear it afterward to avoid __startup_64() adding to it and creating an incorrect value.
Signed-off-by: Jason Andryuk jason.andryuk@amd.com Reviewed-by: Juergen Gross jgross@suse.com Message-ID: 20240823193630.2583107-4-jason.andryuk@amd.com Signed-off-by: Juergen Gross jgross@suse.com Stable-dep-of: e8fbc0d9cab6 ("x86/pvh: Call C code via the kernel virtual mapping") Signed-off-by: Sasha Levin sashal@kernel.org --- arch/x86/platform/pvh/head.S | 13 +++++++++++++ 1 file changed, 13 insertions(+)
diff --git a/arch/x86/platform/pvh/head.S b/arch/x86/platform/pvh/head.S index c4365a05ab83b..c994ea58bdf7a 100644 --- a/arch/x86/platform/pvh/head.S +++ b/arch/x86/platform/pvh/head.S @@ -100,7 +100,20 @@ SYM_CODE_START_LOCAL(pvh_start_xen) xor %edx, %edx wrmsr
+ /* + * Calculate load offset and store in phys_base. __pa() needs + * phys_base set to calculate the hypercall page in xen_pvh_init(). + */ + movq %rbp, %rbx + subq $_pa(pvh_start_xen), %rbx + movq %rbx, phys_base(%rip) call xen_prepare_pvh + /* + * Clear phys_base. __startup_64 will *add* to its value, + * so reset to 0. + */ + xor %rbx, %rbx + movq %rbx, phys_base(%rip)
/* startup_64 expects boot_params in %rsi. */ mov $_pa(pvh_bootparams), %rsi