[PATCH 4.9 007/141] parisc: Fix address in HPMC IVA

Greg Kroah-Hartman
2018-11-11T22:33:38Z

From: John David Anglin <dave.anglin@bell.net>

commit 1138b6718ff74d2a934459643e3754423d23b5e2 upstream.

Helge noticed that the address of the os_hpmc handler was not being
correctly calculated in the hpmc macro. As a result, PDCE_CHECK would
fail to call os_hpmc:

<Cpu2> e800009802e00000 0000000000000000 CC_ERR_CHECK_HPMC
<Cpu2> 37000f7302e00000 8040004000000000 CC_ERR_CPU_CHECK_SUMMARY
<Cpu2> f600105e02e00000 fffffff0f0c00000 CC_MC_HPMC_MONARCH_SELECTED
<Cpu2> 140003b202e00000 000000000000000b CC_ERR_HPMC_STATE_ENTRY
<Cpu2> 5600100b02e00000 00000000000001a0 CC_MC_OS_HPMC_LEN_ERR
<Cpu2> 5600106402e00000 fffffff0f0438e70 CC_MC_BR_TO_OS_HPMC_FAILED
<Cpu2> e800009802e00000 0000000000000000 CC_ERR_CHECK_HPMC
<Cpu2> 37000f7302e00000 8040004000000000 CC_ERR_CPU_CHECK_SUMMARY
<Cpu2> 4000109f02e00000 0000000000000000 CC_MC_HPMC_INITIATED
<Cpu2> 4000101902e00000 0000000000000000 CC_MC_MULTIPLE_HPMCS
<Cpu2> 030010d502e00000 0000000000000000 CC_CPU_STOP

The address problem can be seen by dumping the fault vector:

0000000040159000 <fault_vector_20>:
40159000: 63 6f 77 73 stb r15,-2447(dp)
40159004: 20 63 61 6e ldil L%b747000,r3
40159008: 20 66 6c 79 ldil L%-1c3b3000,r3
...
40159020: 08 00 02 40 nop
40159024: 20 6e 60 02 ldil L%15d000,r3
40159028: 34 63 00 00 ldo 0(r3),r3
4015902c: e8 60 c0 02 bv,n r0(r3)
40159030: 08 00 02 40 nop
40159034: 00 00 00 00 break 0,0
40159038: c0 00 70 00 bb,*< r0,sar,40159840 <fault_vector_20+0x840>
4015903c: 00 00 00 00 break 0,0

Location 40159038 should contain the physical address of os_hpmc:

000000004015d000 <os_hpmc>:
4015d000: 08 1a 02 43 copy r26,r3
4015d004: 01 c0 08 a4 mfctl iva,r4
4015d008: 48 85 00 68 ldw 34(r4),r5

This patch moves the address setup into initialize_ivt to resolve the
above problem. I tested the change by dumping the HPMC entry after setup:

0000000040209020: 8000240
0000000040209024: 206a2004
0000000040209028: 34630ac0
000000004020902c: e860c002
0000000040209030: 8000240
0000000040209034: 1bdddce6
0000000040209038: 15d000
000000004020903c: 1a0

Signed-off-by: John David Anglin <dave.anglin@bell.net>
Cc: <stable@vger.kernel.org>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
arch/parisc/kernel/entry.S | 2 +-
arch/parisc/kernel/traps.c | 3 ++-
2 files changed, 3 insertions(+), 2 deletions(-)

--- a/arch/parisc/kernel/entry.S
+++ b/arch/parisc/kernel/entry.S
@@ -185,7 +185,7 @@
bv,n 0(%r3)
nop
.word 0 /* checksum (will be patched) */
- .word PA(os_hpmc) /* address of handler */
+ .word 0 /* address of handler */
.word 0 /* length of handler */
.endm

--- a/arch/parisc/kernel/traps.c
+++ b/arch/parisc/kernel/traps.c
@@ -826,7 +826,8 @@ void __init initialize_ivt(const void *i
for (i = 0; i < 8; i++)
*ivap++ = 0;

- /* Compute Checksum for HPMC handler */
+ /* Setup IVA and compute checksum for HPMC handler */
+ ivap[6] = (u32)__pa(os_hpmc);
length = os_hpmc_size;
ivap[7] = length;