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-rw-r--r--arch/x86/xen/enlighten.c65
-rw-r--r--arch/x86/xen/enlighten_hvm.c13
-rw-r--r--arch/x86/xen/enlighten_pv.c15
-rw-r--r--arch/x86/xen/enlighten_pvh.c7
-rw-r--r--arch/x86/xen/p2m.c8
-rw-r--r--arch/x86/xen/xen-asm.S50
-rw-r--r--arch/x86/xen/xen-head.S107
-rw-r--r--arch/x86/xen/xen-ops.h9
8 files changed, 211 insertions, 63 deletions
diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index 84e5adbd0925..43dcd8c7badc 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -2,6 +2,7 @@
#include <linux/console.h>
#include <linux/cpu.h>
+#include <linux/instrumentation.h>
#include <linux/kexec.h>
#include <linux/memblock.h>
#include <linux/slab.h>
@@ -21,7 +22,8 @@
#include "xen-ops.h"
-EXPORT_SYMBOL_GPL(hypercall_page);
+DEFINE_STATIC_CALL(xen_hypercall, xen_hypercall_hvm);
+EXPORT_STATIC_CALL_TRAMP(xen_hypercall);
/*
* Pointer to the xen_vcpu_info structure or
@@ -68,6 +70,67 @@ EXPORT_SYMBOL(xen_start_flags);
*/
struct shared_info *HYPERVISOR_shared_info = &xen_dummy_shared_info;
+static __ref void xen_get_vendor(void)
+{
+ init_cpu_devs();
+ cpu_detect(&boot_cpu_data);
+ get_cpu_vendor(&boot_cpu_data);
+}
+
+void xen_hypercall_setfunc(void)
+{
+ if (static_call_query(xen_hypercall) != xen_hypercall_hvm)
+ return;
+
+ if ((boot_cpu_data.x86_vendor == X86_VENDOR_AMD ||
+ boot_cpu_data.x86_vendor == X86_VENDOR_HYGON))
+ static_call_update(xen_hypercall, xen_hypercall_amd);
+ else
+ static_call_update(xen_hypercall, xen_hypercall_intel);
+}
+
+/*
+ * Evaluate processor vendor in order to select the correct hypercall
+ * function for HVM/PVH guests.
+ * Might be called very early in boot before vendor has been set by
+ * early_cpu_init().
+ */
+noinstr void *__xen_hypercall_setfunc(void)
+{
+ void (*func)(void);
+
+ /*
+ * Xen is supported only on CPUs with CPUID, so testing for
+ * X86_FEATURE_CPUID is a test for early_cpu_init() having been
+ * run.
+ *
+ * Note that __xen_hypercall_setfunc() is noinstr only due to a nasty
+ * dependency chain: it is being called via the xen_hypercall static
+ * call when running as a PVH or HVM guest. Hypercalls need to be
+ * noinstr due to PV guests using hypercalls in noinstr code. So we
+ * can safely tag the function body as "instrumentation ok", since
+ * the PV guest requirement is not of interest here (xen_get_vendor()
+ * calls noinstr functions, and static_call_update_early() might do
+ * so, too).
+ */
+ instrumentation_begin();
+
+ if (!boot_cpu_has(X86_FEATURE_CPUID))
+ xen_get_vendor();
+
+ if ((boot_cpu_data.x86_vendor == X86_VENDOR_AMD ||
+ boot_cpu_data.x86_vendor == X86_VENDOR_HYGON))
+ func = xen_hypercall_amd;
+ else
+ func = xen_hypercall_intel;
+
+ static_call_update_early(xen_hypercall, func);
+
+ instrumentation_end();
+
+ return func;
+}
+
static int xen_cpu_up_online(unsigned int cpu)
{
xen_init_lock_cpu(cpu);
diff --git a/arch/x86/xen/enlighten_hvm.c b/arch/x86/xen/enlighten_hvm.c
index 24d2957a4726..fe57ff85d004 100644
--- a/arch/x86/xen/enlighten_hvm.c
+++ b/arch/x86/xen/enlighten_hvm.c
@@ -106,15 +106,8 @@ static void __init init_hvm_pv_info(void)
/* PVH set up hypercall page in xen_prepare_pvh(). */
if (xen_pvh_domain())
pv_info.name = "Xen PVH";
- else {
- u64 pfn;
- uint32_t msr;
-
+ else
pv_info.name = "Xen HVM";
- msr = cpuid_ebx(base + 2);
- pfn = __pa(hypercall_page);
- wrmsr_safe(msr, (u32)pfn, (u32)(pfn >> 32));
- }
xen_setup_features();
@@ -300,6 +293,10 @@ static uint32_t __init xen_platform_hvm(void)
if (xen_pv_domain())
return 0;
+ /* Set correct hypercall function. */
+ if (xen_domain)
+ xen_hypercall_setfunc();
+
if (xen_pvh_domain() && nopv) {
/* Guest booting via the Xen-PVH boot entry goes here */
pr_info("\"nopv\" parameter is ignored in PVH guest\n");
diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c
index d6818c6cafda..5e57835e999d 100644
--- a/arch/x86/xen/enlighten_pv.c
+++ b/arch/x86/xen/enlighten_pv.c
@@ -49,6 +49,7 @@
#include <xen/hvc-console.h>
#include <xen/acpi.h>
+#include <asm/cpuid.h>
#include <asm/paravirt.h>
#include <asm/apic.h>
#include <asm/page.h>
@@ -171,7 +172,7 @@ static void __init xen_set_mtrr_data(void)
/* Only overwrite MTRR state if any MTRR could be got from Xen. */
if (reg)
- mtrr_overwrite_state(var, reg, MTRR_TYPE_UNCACHABLE);
+ guest_force_mtrr_state(var, reg, MTRR_TYPE_UNCACHABLE);
#endif
}
@@ -195,7 +196,7 @@ static void __init xen_pv_init_platform(void)
if (xen_initial_domain())
xen_set_mtrr_data();
else
- mtrr_overwrite_state(NULL, 0, MTRR_TYPE_WRBACK);
+ guest_force_mtrr_state(NULL, 0, MTRR_TYPE_WRBACK);
/* Adjust nr_cpu_ids before "enumeration" happens */
xen_smp_count_cpus();
@@ -230,7 +231,7 @@ static void xen_cpuid(unsigned int *ax, unsigned int *bx,
or_ebx = smp_processor_id() << 24;
break;
- case CPUID_MWAIT_LEAF:
+ case CPUID_LEAF_MWAIT:
/* Synthesize the values.. */
*ax = 0;
*bx = 0;
@@ -300,7 +301,7 @@ static bool __init xen_check_mwait(void)
* ecx and edx. The hypercall provides only partial information.
*/
- ax = CPUID_MWAIT_LEAF;
+ ax = CPUID_LEAF_MWAIT;
bx = 0;
cx = 0;
dx = 0;
@@ -1161,8 +1162,6 @@ static const typeof(pv_ops) xen_cpu_ops __initconst = {
.write_cr4 = xen_write_cr4,
- .wbinvd = pv_native_wbinvd,
-
.read_msr = xen_read_msr,
.write_msr = xen_write_msr,
@@ -1341,6 +1340,9 @@ asmlinkage __visible void __init xen_start_kernel(struct start_info *si)
xen_domain_type = XEN_PV_DOMAIN;
xen_start_flags = xen_start_info->flags;
+ /* Interrupts are guaranteed to be off initially. */
+ early_boot_irqs_disabled = true;
+ static_call_update_early(xen_hypercall, xen_hypercall_pv);
xen_setup_features();
@@ -1431,7 +1433,6 @@ asmlinkage __visible void __init xen_start_kernel(struct start_info *si)
WARN_ON(xen_cpuhp_setup(xen_cpu_up_prepare_pv, xen_cpu_dead_pv));
local_irq_disable();
- early_boot_irqs_disabled = true;
xen_raw_console_write("mapping kernel into physical memory\n");
xen_setup_kernel_pagetable((pgd_t *)xen_start_info->pt_base,
diff --git a/arch/x86/xen/enlighten_pvh.c b/arch/x86/xen/enlighten_pvh.c
index bf68c329fc01..0e3d930bcb89 100644
--- a/arch/x86/xen/enlighten_pvh.c
+++ b/arch/x86/xen/enlighten_pvh.c
@@ -129,17 +129,10 @@ static void __init pvh_arch_setup(void)
void __init xen_pvh_init(struct boot_params *boot_params)
{
- u32 msr;
- u64 pfn;
-
xen_pvh = 1;
xen_domain_type = XEN_HVM_DOMAIN;
xen_start_flags = pvh_start_info.flags;
- msr = cpuid_ebx(xen_cpuid_base() + 2);
- pfn = __pa(hypercall_page);
- wrmsr_safe(msr, (u32)pfn, (u32)(pfn >> 32));
-
x86_init.oem.arch_setup = pvh_arch_setup;
x86_init.oem.banner = xen_banner;
diff --git a/arch/x86/xen/p2m.c b/arch/x86/xen/p2m.c
index b52d3e17e2c1..56914e21e303 100644
--- a/arch/x86/xen/p2m.c
+++ b/arch/x86/xen/p2m.c
@@ -178,13 +178,7 @@ static void p2m_init_identity(unsigned long *p2m, unsigned long pfn)
static void * __ref alloc_p2m_page(void)
{
if (unlikely(!slab_is_available())) {
- void *ptr = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
-
- if (!ptr)
- panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
- __func__, PAGE_SIZE, PAGE_SIZE);
-
- return ptr;
+ return memblock_alloc_or_panic(PAGE_SIZE, PAGE_SIZE);
}
return (void *)__get_free_page(GFP_KERNEL);
diff --git a/arch/x86/xen/xen-asm.S b/arch/x86/xen/xen-asm.S
index 83189cf5cdce..b518f36d1ca2 100644
--- a/arch/x86/xen/xen-asm.S
+++ b/arch/x86/xen/xen-asm.S
@@ -20,10 +20,33 @@
#include <linux/init.h>
#include <linux/linkage.h>
+#include <linux/objtool.h>
#include <../entry/calling.h>
.pushsection .noinstr.text, "ax"
/*
+ * PV hypercall interface to the hypervisor.
+ *
+ * Called via inline asm(), so better preserve %rcx and %r11.
+ *
+ * Input:
+ * %eax: hypercall number
+ * %rdi, %rsi, %rdx, %r10, %r8: args 1..5 for the hypercall
+ * Output: %rax
+ */
+SYM_FUNC_START(xen_hypercall_pv)
+ ANNOTATE_NOENDBR
+ push %rcx
+ push %r11
+ UNWIND_HINT_SAVE
+ syscall
+ UNWIND_HINT_RESTORE
+ pop %r11
+ pop %rcx
+ RET
+SYM_FUNC_END(xen_hypercall_pv)
+
+/*
* Disabling events is simply a matter of making the event mask
* non-zero.
*/
@@ -176,7 +199,6 @@ SYM_CODE_START(xen_early_idt_handler_array)
SYM_CODE_END(xen_early_idt_handler_array)
__FINIT
-hypercall_iret = hypercall_page + __HYPERVISOR_iret * 32
/*
* Xen64 iret frame:
*
@@ -186,17 +208,28 @@ hypercall_iret = hypercall_page + __HYPERVISOR_iret * 32
* cs
* rip <-- standard iret frame
*
- * flags
+ * flags <-- xen_iret must push from here on
*
- * rcx }
- * r11 }<-- pushed by hypercall page
- * rsp->rax }
+ * rcx
+ * r11
+ * rsp->rax
*/
+.macro xen_hypercall_iret
+ pushq $0 /* Flags */
+ push %rcx
+ push %r11
+ push %rax
+ mov $__HYPERVISOR_iret, %eax
+ syscall /* Do the IRET. */
+#ifdef CONFIG_MITIGATION_SLS
+ int3
+#endif
+.endm
+
SYM_CODE_START(xen_iret)
UNWIND_HINT_UNDEFINED
ANNOTATE_NOENDBR
- pushq $0
- jmp hypercall_iret
+ xen_hypercall_iret
SYM_CODE_END(xen_iret)
/*
@@ -301,8 +334,7 @@ SYM_CODE_START(xen_entry_SYSENTER_compat)
ENDBR
lea 16(%rsp), %rsp /* strip %rcx, %r11 */
mov $-ENOSYS, %rax
- pushq $0
- jmp hypercall_iret
+ xen_hypercall_iret
SYM_CODE_END(xen_entry_SYSENTER_compat)
SYM_CODE_END(xen_entry_SYSCALL_compat)
diff --git a/arch/x86/xen/xen-head.S b/arch/x86/xen/xen-head.S
index 7f6c69dbb816..9252652afe59 100644
--- a/arch/x86/xen/xen-head.S
+++ b/arch/x86/xen/xen-head.S
@@ -6,9 +6,11 @@
#include <linux/elfnote.h>
#include <linux/init.h>
+#include <linux/instrumentation.h>
#include <asm/boot.h>
#include <asm/asm.h>
+#include <asm/frame.h>
#include <asm/msr.h>
#include <asm/page_types.h>
#include <asm/percpu.h>
@@ -20,28 +22,6 @@
#include <xen/interface/xen-mca.h>
#include <asm/xen/interface.h>
-.pushsection .noinstr.text, "ax"
- .balign PAGE_SIZE
-SYM_CODE_START(hypercall_page)
- .rept (PAGE_SIZE / 32)
- UNWIND_HINT_FUNC
- ANNOTATE_NOENDBR
- ANNOTATE_UNRET_SAFE
- ret
- /*
- * Xen will write the hypercall page, and sort out ENDBR.
- */
- .skip 31, 0xcc
- .endr
-
-#define HYPERCALL(n) \
- .equ xen_hypercall_##n, hypercall_page + __HYPERVISOR_##n * 32; \
- .type xen_hypercall_##n, @function; .size xen_hypercall_##n, 32
-#include <asm/xen-hypercalls.h>
-#undef HYPERCALL
-SYM_CODE_END(hypercall_page)
-.popsection
-
#ifdef CONFIG_XEN_PV
__INIT
SYM_CODE_START(startup_xen)
@@ -87,6 +67,87 @@ SYM_CODE_END(xen_cpu_bringup_again)
#endif
#endif
+ .pushsection .noinstr.text, "ax"
+/*
+ * Xen hypercall interface to the hypervisor.
+ *
+ * Input:
+ * %eax: hypercall number
+ * 32-bit:
+ * %ebx, %ecx, %edx, %esi, %edi: args 1..5 for the hypercall
+ * 64-bit:
+ * %rdi, %rsi, %rdx, %r10, %r8: args 1..5 for the hypercall
+ * Output: %[er]ax
+ */
+SYM_FUNC_START(xen_hypercall_hvm)
+ ENDBR
+ FRAME_BEGIN
+ /* Save all relevant registers (caller save and arguments). */
+#ifdef CONFIG_X86_32
+ push %eax
+ push %ebx
+ push %ecx
+ push %edx
+ push %esi
+ push %edi
+#else
+ push %rax
+ push %rcx
+ push %rdx
+ push %rdi
+ push %rsi
+ push %r11
+ push %r10
+ push %r9
+ push %r8
+#ifdef CONFIG_FRAME_POINTER
+ pushq $0 /* Dummy push for stack alignment. */
+#endif
+#endif
+ /* Set the vendor specific function. */
+ call __xen_hypercall_setfunc
+ /* Set ZF = 1 if AMD, Restore saved registers. */
+#ifdef CONFIG_X86_32
+ lea xen_hypercall_amd, %ebx
+ cmp %eax, %ebx
+ pop %edi
+ pop %esi
+ pop %edx
+ pop %ecx
+ pop %ebx
+ pop %eax
+#else
+ lea xen_hypercall_amd(%rip), %rbx
+ cmp %rax, %rbx
+#ifdef CONFIG_FRAME_POINTER
+ pop %rax /* Dummy pop. */
+#endif
+ pop %r8
+ pop %r9
+ pop %r10
+ pop %r11
+ pop %rsi
+ pop %rdi
+ pop %rdx
+ pop %rcx
+ pop %rax
+#endif
+ /* Use correct hypercall function. */
+ jz xen_hypercall_amd
+ jmp xen_hypercall_intel
+SYM_FUNC_END(xen_hypercall_hvm)
+
+SYM_FUNC_START(xen_hypercall_amd)
+ vmmcall
+ RET
+SYM_FUNC_END(xen_hypercall_amd)
+
+SYM_FUNC_START(xen_hypercall_intel)
+ vmcall
+ RET
+SYM_FUNC_END(xen_hypercall_intel)
+ .popsection
+
ELFNOTE(Xen, XEN_ELFNOTE_GUEST_OS, .asciz "linux")
ELFNOTE(Xen, XEN_ELFNOTE_GUEST_VERSION, .asciz "2.6")
ELFNOTE(Xen, XEN_ELFNOTE_XEN_VERSION, .asciz "xen-3.0")
@@ -116,8 +177,6 @@ SYM_CODE_END(xen_cpu_bringup_again)
#else
# define FEATURES_DOM0 0
#endif
- ELFNOTE(Xen, XEN_ELFNOTE_HYPERCALL_PAGE, .globl xen_elfnote_hypercall_page;
- xen_elfnote_hypercall_page: _ASM_PTR xen_elfnote_hypercall_page_value - .)
ELFNOTE(Xen, XEN_ELFNOTE_SUPPORTED_FEATURES,
.long FEATURES_PV | FEATURES_PVH | FEATURES_DOM0)
ELFNOTE(Xen, XEN_ELFNOTE_LOADER, .asciz "generic")
diff --git a/arch/x86/xen/xen-ops.h b/arch/x86/xen/xen-ops.h
index e1b782e823e6..63c13a2ccf55 100644
--- a/arch/x86/xen/xen-ops.h
+++ b/arch/x86/xen/xen-ops.h
@@ -326,4 +326,13 @@ static inline void xen_smp_intr_free_pv(unsigned int cpu) {}
static inline void xen_smp_count_cpus(void) { }
#endif /* CONFIG_SMP */
+#ifdef CONFIG_XEN_PV
+void xen_hypercall_pv(void);
+#endif
+void xen_hypercall_hvm(void);
+void xen_hypercall_amd(void);
+void xen_hypercall_intel(void);
+void xen_hypercall_setfunc(void);
+void *__xen_hypercall_setfunc(void);
+
#endif /* XEN_OPS_H */