powerpc: Restore VDSO information on critical exception om BookE

Critical exception on 64-bit booke uses user-visible SPRG3 as scratch.
Restore VDSO information in SPRG3 on exception prolog.

Use a common sprg3 field in PACA for all powerpc64 architectures.

Signed-off-by: Mihai Caraman <mihai.caraman@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

diff --git a/arch/powerpc/include/asm/kvm_book3s_asm.h b/arch/powerpc/include/asm/kvm_book3s_asm.h
index bfcd00c..88609b2 100644 (file)
--- a/arch/powerpc/include/asm/kvm_book3s_asm.h
+++ b/arch/powerpc/include/asm/kvm_book3s_asm.h
@@ -74,7 +74,6 @@ struct kvmppc_host_state {
        ulong vmhandler;
        ulong scratch0;
        ulong scratch1;
-       ulong sprg3;
        u8 in_guest;
        u8 restore_hid5;
        u8 napping;

diff --git a/arch/powerpc/include/asm/paca.h b/arch/powerpc/include/asm/paca.h
index daf813f..7796519 100644 (file)
--- a/arch/powerpc/include/asm/paca.h
+++ b/arch/powerpc/include/asm/paca.h
@@ -136,6 +136,7 @@ struct paca_struct {
        u8 io_sync;                     /* writel() needs spin_unlock sync */
        u8 irq_work_pending;            /* IRQ_WORK interrupt while soft-disable */
        u8 nap_state_lost;              /* NV GPR values lost in power7_idle */
+       u64 sprg3;                      /* Saved user-visible sprg */
 
 #ifdef CONFIG_PPC_POWERNV
        /* Pointer to OPAL machine check event structure set by the

diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c
index 85b05c4..72f2616 100644 (file)
--- a/arch/powerpc/kernel/asm-offsets.c
+++ b/arch/powerpc/kernel/asm-offsets.c
@@ -205,6 +205,7 @@ int main(void)
        DEFINE(PACA_SYSTEM_TIME, offsetof(struct paca_struct, system_time));
        DEFINE(PACA_TRAP_SAVE, offsetof(struct paca_struct, trap_save));
        DEFINE(PACA_NAPSTATELOST, offsetof(struct paca_struct, nap_state_lost));
+       DEFINE(PACA_SPRG3, offsetof(struct paca_struct, sprg3));
 #endif /* CONFIG_PPC64 */
 
        /* RTAS */
@@ -533,7 +534,6 @@ int main(void)
        HSTATE_FIELD(HSTATE_VMHANDLER, vmhandler);
        HSTATE_FIELD(HSTATE_SCRATCH0, scratch0);
        HSTATE_FIELD(HSTATE_SCRATCH1, scratch1);
-       HSTATE_FIELD(HSTATE_SPRG3, sprg3);
        HSTATE_FIELD(HSTATE_IN_GUEST, in_guest);
        HSTATE_FIELD(HSTATE_RESTORE_HID5, restore_hid5);
        HSTATE_FIELD(HSTATE_NAPPING, napping);

diff --git a/arch/powerpc/kernel/exceptions-64e.S b/arch/powerpc/kernel/exceptions-64e.S
index 7476b0a..87a82fb 100644 (file)
--- a/arch/powerpc/kernel/exceptions-64e.S
+++ b/arch/powerpc/kernel/exceptions-64e.S
@@ -110,7 +110,9 @@
 
 #define PROLOG_STORE_RESTORE_SCRATCH_CRIT                                  \
        mfspr   r10,SPRN_SPRG_CRIT_SCRATCH;     /* get r13 */               \
-       std     r10,PACA_EXCRIT+EX_R13(r13)
+       std     r10,PACA_EXCRIT+EX_R13(r13);                                \
+       ld      r11,PACA_SPRG3(r13);                                        \
+       mtspr   SPRN_SPRG_CRIT_SCRATCH,r11;
 
 /* Variants of the "addition" argument for the prolog
  */

diff --git a/arch/powerpc/kernel/vdso.c b/arch/powerpc/kernel/vdso.c
index b67db22..1b2076f 100644 (file)
--- a/arch/powerpc/kernel/vdso.c
+++ b/arch/powerpc/kernel/vdso.c
@@ -723,9 +723,7 @@ int __cpuinit vdso_getcpu_init(void)
 
        val = (cpu & 0xfff) | ((node & 0xffff) << 16);
        mtspr(SPRN_SPRG3, val);
-#ifdef CONFIG_KVM_BOOK3S_HANDLER
-       get_paca()->kvm_hstate.sprg3 = val;
-#endif
+       get_paca()->sprg3 = val;
 
        put_cpu();
 

diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
index 5a84c8d..39a21bf 100644 (file)
--- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
+++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
@@ -1065,7 +1065,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_206)
        mtspr   SPRN_DABRX,r6
 
        /* Restore SPRG3 */
-       ld      r3,HSTATE_SPRG3(r13)
+       ld      r3,PACA_SPRG3(r13)
        mtspr   SPRN_SPRG3,r3
 
        /*