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>
---
v2:
Fix comment style
Add Juergen's R-b
s/LOAD_PHYSICAL_ADDR/_pa(pvh_start_xen)/ in case they differ
---
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 ba4d0eab4436..14b4345d9bae 100644
--- a/arch/x86/platform/pvh/head.S
+++ b/arch/x86/platform/pvh/head.S
@@ -125,7 +125,20 @@ 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. */
lea pvh_bootparams(%rip), %rsi
--
2.34.1