arm: Remove the ability to set HYP vectors outside of the decompressor

Although we have to bounce between HYP and SVC to decompress and
relocate the kernel, we don't need to be able to use it in the
kernel itself. So let's drop the functionnality.

Since the vectors are never changed, there is no need to reset them
either, and nobody calls that stub anyway. The last function
(SOFT_RESTART) is still present in order to support kexec.

Signed-off-by: Marc Zyngier <maz@kernel.org>

diff --git a/arch/arm/include/asm/virt.h b/arch/arm/include/asm/virt.h
index 47600a5894b1796b0c497aa2ab46ca218e1cb343..dd9697b2bde8091aa5711f86db1d5130a570abb1 100644 (file)
--- a/arch/arm/include/asm/virt.h
+++ b/arch/arm/include/asm/virt.h
@@ -39,8 +39,6 @@ static inline void sync_boot_mode(void)
        sync_cache_r(&__boot_cpu_mode);
 }
 
-void __hyp_set_vectors(unsigned long phys_vector_base);
-void __hyp_reset_vectors(void);
 #else
 #define __boot_cpu_mode        (SVC_MODE)
 #define sync_boot_mode()
@@ -75,9 +73,6 @@ static inline bool is_kernel_in_hyp_mode(void)
 
 #define HVC_SET_VECTORS 0
 #define HVC_SOFT_RESTART 1
-#define HVC_RESET_VECTORS 2
-
-#define HVC_STUB_HCALL_NR 3
 
 #endif /* __ASSEMBLY__ */
 

diff --git a/arch/arm/kernel/hyp-stub.S b/arch/arm/kernel/hyp-stub.S
index 6607fa817bba9a5510ac0a0c2de88342a80dfdb9..26d8e03b1dd336daecabcdba10480ffa83801d2a 100644 (file)
--- a/arch/arm/kernel/hyp-stub.S
+++ b/arch/arm/kernel/hyp-stub.S
@@ -189,19 +189,19 @@ ARM_BE8(orr       r7, r7, #(1 << 25))     @ HSCTLR.EE
 ENDPROC(__hyp_stub_install_secondary)
 
 __hyp_stub_do_trap:
+#ifdef ZIMAGE
        teq     r0, #HVC_SET_VECTORS
        bne     1f
+       /* Only the ZIMAGE stubs can change the HYP vectors */
        mcr     p15, 4, r1, c12, c0, 0  @ set HVBAR
        b       __hyp_stub_exit
+#endif
 
 1:     teq     r0, #HVC_SOFT_RESTART
-       bne     1f
+       bne     2f
        bx      r1
 
-1:     teq     r0, #HVC_RESET_VECTORS
-       beq     __hyp_stub_exit
-
-       ldr     r0, =HVC_STUB_ERR
+2:     ldr     r0, =HVC_STUB_ERR
        __ERET
 
 __hyp_stub_exit:
@@ -210,26 +210,9 @@ __hyp_stub_exit:
 ENDPROC(__hyp_stub_do_trap)
 
 /*
- * __hyp_set_vectors: Call this after boot to set the initial hypervisor
- * vectors as part of hypervisor installation.  On an SMP system, this should
- * be called on each CPU.
- *
- * r0 must be the physical address of the new vector table (which must lie in
- * the bottom 4GB of physical address space.
- *
- * r0 must be 32-byte aligned.
- *
- * Before calling this, you must check that the stub hypervisor is installed
- * everywhere, by waiting for any secondary CPUs to be brought up and then
- * checking that BOOT_CPU_MODE_HAVE_HYP(__boot_cpu_mode) is true.
- *
- * If not, there is a pre-existing hypervisor, some CPUs failed to boot, or
- * something else went wrong... in such cases, trying to install a new
- * hypervisor is unlikely to work as desired.
- *
- * When you call into your shiny new hypervisor, sp_hyp will contain junk,
- * so you will need to set that to something sensible at the new hypervisor's
- * initialisation entry point.
+ * __hyp_set_vectors is only used when ZIMAGE must bounce between HYP
+ * and SVC. For the kernel itself, the vectors are set once and for
+ * all by the stubs.
  */
 ENTRY(__hyp_set_vectors)
        mov     r1, r0
@@ -245,12 +228,6 @@ ENTRY(__hyp_soft_restart)
        ret     lr
 ENDPROC(__hyp_soft_restart)
 
-ENTRY(__hyp_reset_vectors)
-       mov     r0, #HVC_RESET_VECTORS
-       __HVC(0)
-       ret     lr
-ENDPROC(__hyp_reset_vectors)
-
 #ifndef ZIMAGE
 .align 2
 .L__boot_cpu_mode_offset: