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powerpc: Fix "attempt to move .org backwards" error
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With recent machine check patch series changes, The exception vectors
starting from 0x4300 are now overflowing with allyesconfig. Fix that by
moving machine_check_common and machine_check_handle_early code out of
that region to make enough room for exception vector area.

Fixes this build error reportes by Stephen:

arch/powerpc/kernel/exceptions-64s.S: Assembler messages:
arch/powerpc/kernel/exceptions-64s.S:958: Error: attempt to move .org backwards
arch/powerpc/kernel/exceptions-64s.S:959: Error: attempt to move .org backwards
arch/powerpc/kernel/exceptions-64s.S:983: Error: attempt to move .org backwards
arch/powerpc/kernel/exceptions-64s.S:984: Error: attempt to move .org backwards
arch/powerpc/kernel/exceptions-64s.S:1003: Error: attempt to move .org backwards
arch/powerpc/kernel/exceptions-64s.S:1013: Error: attempt to move .org backwards
arch/powerpc/kernel/exceptions-64s.S:1014: Error: attempt to move .org backwards
arch/powerpc/kernel/exceptions-64s.S:1015: Error: attempt to move .org backwards
arch/powerpc/kernel/exceptions-64s.S:1016: Error: attempt to move .org backwards
arch/powerpc/kernel/exceptions-64s.S:1017: Error: attempt to move .org backwards
arch/powerpc/kernel/exceptions-64s.S:1018: Error: attempt to move .org backwards

[Moved the code further down as it introduced link errors due to too long
 relative branches to the masked interrupts handlers from the exception
 prologs. Also removed the useless feature section --BenH
]

Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Tested-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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Mahesh Salgaonkar authored and Benjamin Herrenschmidt committed Dec 30, 2013
1 parent 75eb3d9 commit 4e243b7
Showing 1 changed file with 138 additions and 140 deletions.
278 changes: 138 additions & 140 deletions arch/powerpc/kernel/exceptions-64s.S
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Original file line number Diff line number Diff line change
Expand Up @@ -768,146 +768,6 @@ kvmppc_skip_Hinterrupt:

STD_EXCEPTION_COMMON(0x100, system_reset, .system_reset_exception)

/*
* Machine check is different because we use a different
* save area: PACA_EXMC instead of PACA_EXGEN.
*/
.align 7
.globl machine_check_common
machine_check_common:

mfspr r10,SPRN_DAR
std r10,PACA_EXGEN+EX_DAR(r13)
mfspr r10,SPRN_DSISR
stw r10,PACA_EXGEN+EX_DSISR(r13)
EXCEPTION_PROLOG_COMMON(0x200, PACA_EXMC)
FINISH_NAP
DISABLE_INTS
ld r3,PACA_EXGEN+EX_DAR(r13)
lwz r4,PACA_EXGEN+EX_DSISR(r13)
std r3,_DAR(r1)
std r4,_DSISR(r1)
bl .save_nvgprs
addi r3,r1,STACK_FRAME_OVERHEAD
bl .machine_check_exception
b .ret_from_except

#define MACHINE_CHECK_HANDLER_WINDUP \
/* Clear MSR_RI before setting SRR0 and SRR1. */\
li r0,MSR_RI; \
mfmsr r9; /* get MSR value */ \
andc r9,r9,r0; \
mtmsrd r9,1; /* Clear MSR_RI */ \
/* Move original SRR0 and SRR1 into the respective regs */ \
ld r9,_MSR(r1); \
mtspr SPRN_SRR1,r9; \
ld r3,_NIP(r1); \
mtspr SPRN_SRR0,r3; \
ld r9,_CTR(r1); \
mtctr r9; \
ld r9,_XER(r1); \
mtxer r9; \
ld r9,_LINK(r1); \
mtlr r9; \
REST_GPR(0, r1); \
REST_8GPRS(2, r1); \
REST_GPR(10, r1); \
ld r11,_CCR(r1); \
mtcr r11; \
/* Decrement paca->in_mce. */ \
lhz r12,PACA_IN_MCE(r13); \
subi r12,r12,1; \
sth r12,PACA_IN_MCE(r13); \
REST_GPR(11, r1); \
REST_2GPRS(12, r1); \
/* restore original r1. */ \
ld r1,GPR1(r1)

/*
* Handle machine check early in real mode. We come here with
* ME=1, MMU (IR=0 and DR=0) off and using MC emergency stack.
*/
.align 7
.globl machine_check_handle_early
machine_check_handle_early:
BEGIN_FTR_SECTION
std r0,GPR0(r1) /* Save r0 */
EXCEPTION_PROLOG_COMMON_3(0x200)
bl .save_nvgprs
addi r3,r1,STACK_FRAME_OVERHEAD
bl .machine_check_early
ld r12,_MSR(r1)
#ifdef CONFIG_PPC_P7_NAP
/*
* Check if thread was in power saving mode. We come here when any
* of the following is true:
* a. thread wasn't in power saving mode
* b. thread was in power saving mode with no state loss or
* supervisor state loss
*
* Go back to nap again if (b) is true.
*/
rlwinm. r11,r12,47-31,30,31 /* Was it in power saving mode? */
beq 4f /* No, it wasn;t */
/* Thread was in power saving mode. Go back to nap again. */
cmpwi r11,2
bne 3f
/* Supervisor state loss */
li r0,1
stb r0,PACA_NAPSTATELOST(r13)
3: bl .machine_check_queue_event
MACHINE_CHECK_HANDLER_WINDUP
GET_PACA(r13)
ld r1,PACAR1(r13)
b .power7_enter_nap_mode
4:
#endif
/*
* Check if we are coming from hypervisor userspace. If yes then we
* continue in host kernel in V mode to deliver the MC event.
*/
rldicl. r11,r12,4,63 /* See if MC hit while in HV mode. */
beq 5f
andi. r11,r12,MSR_PR /* See if coming from user. */
bne 9f /* continue in V mode if we are. */

5:
#ifdef CONFIG_KVM_BOOK3S_64_HV
/*
* We are coming from kernel context. Check if we are coming from
* guest. if yes, then we can continue. We will fall through
* do_kvm_200->kvmppc_interrupt to deliver the MC event to guest.
*/
lbz r11,HSTATE_IN_GUEST(r13)
cmpwi r11,0 /* Check if coming from guest */
bne 9f /* continue if we are. */
#endif
/*
* At this point we are not sure about what context we come from.
* Queue up the MCE event and return from the interrupt.
* But before that, check if this is an un-recoverable exception.
* If yes, then stay on emergency stack and panic.
*/
andi. r11,r12,MSR_RI
bne 2f
1: addi r3,r1,STACK_FRAME_OVERHEAD
bl .unrecoverable_exception
b 1b
2:
/*
* Return from MC interrupt.
* Queue up the MCE event so that we can log it later, while
* returning from kernel or opal call.
*/
bl .machine_check_queue_event
MACHINE_CHECK_HANDLER_WINDUP
rfid
9:
/* Deliver the machine check to host kernel in V mode. */
MACHINE_CHECK_HANDLER_WINDUP
b machine_check_pSeries
END_FTR_SECTION_IFSET(CPU_FTR_HVMODE)

STD_EXCEPTION_COMMON_ASYNC(0x500, hardware_interrupt, do_IRQ)
STD_EXCEPTION_COMMON_ASYNC(0x900, decrementer, .timer_interrupt)
STD_EXCEPTION_COMMON(0x980, hdecrementer, .hdec_interrupt)
Expand Down Expand Up @@ -1276,6 +1136,30 @@ unrecov_user_slb:
#endif /* __DISABLED__ */


/*
* Machine check is different because we use a different
* save area: PACA_EXMC instead of PACA_EXGEN.
*/
.align 7
.globl machine_check_common
machine_check_common:

mfspr r10,SPRN_DAR
std r10,PACA_EXGEN+EX_DAR(r13)
mfspr r10,SPRN_DSISR
stw r10,PACA_EXGEN+EX_DSISR(r13)
EXCEPTION_PROLOG_COMMON(0x200, PACA_EXMC)
FINISH_NAP
DISABLE_INTS
ld r3,PACA_EXGEN+EX_DAR(r13)
lwz r4,PACA_EXGEN+EX_DSISR(r13)
std r3,_DAR(r1)
std r4,_DSISR(r1)
bl .save_nvgprs
addi r3,r1,STACK_FRAME_OVERHEAD
bl .machine_check_exception
b .ret_from_except

.align 7
.globl alignment_common
alignment_common:
Expand Down Expand Up @@ -1459,6 +1343,120 @@ _GLOBAL(opal_mc_secondary_handler)
#endif /* CONFIG_PPC_POWERNV */


#define MACHINE_CHECK_HANDLER_WINDUP \
/* Clear MSR_RI before setting SRR0 and SRR1. */\
li r0,MSR_RI; \
mfmsr r9; /* get MSR value */ \
andc r9,r9,r0; \
mtmsrd r9,1; /* Clear MSR_RI */ \
/* Move original SRR0 and SRR1 into the respective regs */ \
ld r9,_MSR(r1); \
mtspr SPRN_SRR1,r9; \
ld r3,_NIP(r1); \
mtspr SPRN_SRR0,r3; \
ld r9,_CTR(r1); \
mtctr r9; \
ld r9,_XER(r1); \
mtxer r9; \
ld r9,_LINK(r1); \
mtlr r9; \
REST_GPR(0, r1); \
REST_8GPRS(2, r1); \
REST_GPR(10, r1); \
ld r11,_CCR(r1); \
mtcr r11; \
/* Decrement paca->in_mce. */ \
lhz r12,PACA_IN_MCE(r13); \
subi r12,r12,1; \
sth r12,PACA_IN_MCE(r13); \
REST_GPR(11, r1); \
REST_2GPRS(12, r1); \
/* restore original r1. */ \
ld r1,GPR1(r1)

/*
* Handle machine check early in real mode. We come here with
* ME=1, MMU (IR=0 and DR=0) off and using MC emergency stack.
*/
.align 7
.globl machine_check_handle_early
machine_check_handle_early:
std r0,GPR0(r1) /* Save r0 */
EXCEPTION_PROLOG_COMMON_3(0x200)
bl .save_nvgprs
addi r3,r1,STACK_FRAME_OVERHEAD
bl .machine_check_early
ld r12,_MSR(r1)
#ifdef CONFIG_PPC_P7_NAP
/*
* Check if thread was in power saving mode. We come here when any
* of the following is true:
* a. thread wasn't in power saving mode
* b. thread was in power saving mode with no state loss or
* supervisor state loss
*
* Go back to nap again if (b) is true.
*/
rlwinm. r11,r12,47-31,30,31 /* Was it in power saving mode? */
beq 4f /* No, it wasn;t */
/* Thread was in power saving mode. Go back to nap again. */
cmpwi r11,2
bne 3f
/* Supervisor state loss */
li r0,1
stb r0,PACA_NAPSTATELOST(r13)
3: bl .machine_check_queue_event
MACHINE_CHECK_HANDLER_WINDUP
GET_PACA(r13)
ld r1,PACAR1(r13)
b .power7_enter_nap_mode
4:
#endif
/*
* Check if we are coming from hypervisor userspace. If yes then we
* continue in host kernel in V mode to deliver the MC event.
*/
rldicl. r11,r12,4,63 /* See if MC hit while in HV mode. */
beq 5f
andi. r11,r12,MSR_PR /* See if coming from user. */
bne 9f /* continue in V mode if we are. */

5:
#ifdef CONFIG_KVM_BOOK3S_64_HV
/*
* We are coming from kernel context. Check if we are coming from
* guest. if yes, then we can continue. We will fall through
* do_kvm_200->kvmppc_interrupt to deliver the MC event to guest.
*/
lbz r11,HSTATE_IN_GUEST(r13)
cmpwi r11,0 /* Check if coming from guest */
bne 9f /* continue if we are. */
#endif
/*
* At this point we are not sure about what context we come from.
* Queue up the MCE event and return from the interrupt.
* But before that, check if this is an un-recoverable exception.
* If yes, then stay on emergency stack and panic.
*/
andi. r11,r12,MSR_RI
bne 2f
1: addi r3,r1,STACK_FRAME_OVERHEAD
bl .unrecoverable_exception
b 1b
2:
/*
* Return from MC interrupt.
* Queue up the MCE event so that we can log it later, while
* returning from kernel or opal call.
*/
bl .machine_check_queue_event
MACHINE_CHECK_HANDLER_WINDUP
rfid
9:
/* Deliver the machine check to host kernel in V mode. */
MACHINE_CHECK_HANDLER_WINDUP
b machine_check_pSeries

/*
* r13 points to the PACA, r9 contains the saved CR,
* r12 contain the saved SRR1, SRR0 is still ready for return
Expand Down

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