From: Nicholas Piggin <npiggin@gmail•com>
To: linuxppc-dev@lists•ozlabs.org
Cc: Nicholas Piggin <npiggin@gmail•com>
Subject: [PATCH v2 49/52] powerpc/64s/exceptions: machine check move unrecoverable handling out of line
Date: Thu, 20 Jun 2019 15:14:56 +1000 [thread overview]
Message-ID: <20190620051459.29573-50-npiggin@gmail.com> (raw)
In-Reply-To: <20190620051459.29573-1-npiggin@gmail.com>
Similarly to the previous patch, move unrecoverable handling out of
line, which makes the regular path less cluttered and easier to
follow.
Signed-off-by: Nicholas Piggin <npiggin@gmail•com>
---
arch/powerpc/kernel/exceptions-64s.S | 83 +++++++++++++---------------
1 file changed, 39 insertions(+), 44 deletions(-)
diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S
index be83a4e71814..e8f644d6f310 100644
--- a/arch/powerpc/kernel/exceptions-64s.S
+++ b/arch/powerpc/kernel/exceptions-64s.S
@@ -1016,9 +1016,9 @@ EXC_COMMON_BEGIN(machine_check_early_common)
bne 1f
/* First machine check entry */
ld r1,PACAMCEMERGSP(r13) /* Use MC emergency stack */
-1: subi r1,r1,INT_FRAME_SIZE /* alloc stack frame */
- /* Limit nested MCE to level 4 to avoid stack overflow */
- bge cr1,2f /* Check if we hit limit of 4 */
+1: /* Limit nested MCE to level 4 to avoid stack overflow */
+ bgt cr1,unrecoverable_mce /* Check if we hit limit of 4 */
+ subi r1,r1,INT_FRAME_SIZE /* alloc stack frame */
EXCEPTION_PROLOG_COMMON_1()
/* We don't touch AMR here, we never go to virtual mode */
@@ -1032,25 +1032,9 @@ EXC_COMMON_BEGIN(machine_check_early_common)
li r10,MSR_RI
mtmsrd r10,1
-
bl enable_machine_check
b machine_check_handle_early
-2:
- /* Stack overflow. Stay on emergency stack and panic.
- * Keep the ME bit off while panic-ing, so that if we hit
- * another machine check we checkstop.
- */
- addi r1,r1,INT_FRAME_SIZE /* go back to previous stack frame */
- ld r11,PACAKMSR(r13)
- LOAD_HANDLER(r12, unrecover_mce)
- li r10,MSR_ME
- andc r11,r11,r10 /* Turn off MSR_ME */
- mtspr SPRN_SRR0,r12
- mtspr SPRN_SRR1,r11
- RFI_TO_KERNEL
- b . /* prevent speculative execution */
-
EXC_COMMON_BEGIN(machine_check_common)
/*
* Machine check is different because we use a different
@@ -1166,32 +1150,15 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_206)
* If yes, then stay on emergency stack and panic.
*/
andi. r11,r12,MSR_RI
- bne 2f
-1: mfspr r11,SPRN_SRR0
- LOAD_HANDLER(r10,unrecover_mce)
- mtspr SPRN_SRR0,r10
- ld r10,PACAKMSR(r13)
- /*
- * We are going down. But there are chances that we might get hit by
- * another MCE during panic path and we may run into unstable state
- * with no way out. Hence, turn ME bit off while going down, so that
- * when another MCE is hit during panic path, system will checkstop
- * and hypervisor will get restarted cleanly by SP.
- */
- li r3,MSR_ME
- andc r10,r10,r3 /* Turn off MSR_ME */
- mtspr SPRN_SRR1,r10
- RFI_TO_KERNEL
- b .
-2:
+ beq unrecoverable_mce
+
/*
* Check if we have successfully handled/recovered from error, if not
* then stay on emergency stack and panic.
*/
ld r3,RESULT(r1) /* Load result */
cmpdi r3,0 /* see if we handled MCE successfully */
-
- beq 1b /* if !handled then panic */
+ beq unrecoverable_mce /* if !handled then panic */
/*
* Return from MC interrupt.
@@ -1213,17 +1180,31 @@ END_FTR_SECTION_IFSET(CPU_FTR_CFAR)
EXCEPTION_PROLOG_1 EXC_STD, PACA_EXMC, 1, 0x200, 1, 1, 0
EXCEPTION_PROLOG_2_REAL machine_check_common, EXC_STD, 0
-EXC_COMMON_BEGIN(unrecover_mce)
+EXC_COMMON_BEGIN(unrecoverable_mce)
+ /*
+ * We are going down. But there are chances that we might get hit by
+ * another MCE during panic path and we may run into unstable state
+ * with no way out. Hence, turn ME bit off while going down, so that
+ * when another MCE is hit during panic path, system will checkstop
+ * and hypervisor will get restarted cleanly by SP.
+ */
+ bl disable_machine_check
+ ld r10,PACAKMSR(r13)
+ li r3,MSR_ME
+ andc r10,r10,r3
+ mtmsrd r10
+
/* Invoke machine_check_exception to print MCE event and panic. */
addi r3,r1,STACK_FRAME_OVERHEAD
bl machine_check_exception
+
/*
- * We will not reach here. Even if we did, there is no way out. Call
- * unrecoverable_exception and die.
+ * We will not reach here. Even if we did, there is no way out.
+ * Call unrecoverable_exception and die.
*/
-1: addi r3,r1,STACK_FRAME_OVERHEAD
+ addi r3,r1,STACK_FRAME_OVERHEAD
bl unrecoverable_exception
- b 1b
+ b .
EXC_REAL_BEGIN(data_access, 0x300, 0x80)
@@ -2297,6 +2278,20 @@ enable_machine_check:
1: mtlr r0
blr
+disable_machine_check:
+ mflr r0
+ bcl 20,31,$+4
+0: mflr r3
+ addi r3,r3,(1f - 0b)
+ mtspr SPRN_SRR0,r3
+ mfmsr r3
+ li r4,MSR_ME
+ andc r3,r3,r4
+ mtspr SPRN_SRR1,r3
+ RFI_TO_KERNEL
+1: mtlr r0
+ blr
+
/*
* Hash table stuff
*/
--
2.20.1
next prev parent reply other threads:[~2019-06-20 6:59 UTC|newest]
Thread overview: 59+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-06-20 5:14 [PATCH v2 00/52] powerpc/64s interrupt handler cleanups, gasification Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 01/52] powerpc/64s/exception: fix line wrap and semicolon inconsistencies in macros Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 02/52] powerpc/64s/exception: remove H concatenation for EXC_HV variants Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 03/52] powerpc/64s/exception: consolidate EXCEPTION_PROLOG_2 with _NORI variant Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 04/52] powerpc/64s/exception: move and tidy EXCEPTION_PROLOG_2 variants Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 05/52] powerpc/64s/exception: fix sreset KVM test code Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 06/52] powerpc/64s/exception: remove the "extra" macro parameter Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 07/52] powerpc/64s/exception: consolidate maskable and non-maskable prologs Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 08/52] powerpc/64s/exception: merge KVM handler and skip variants Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 09/52] powerpc/64s/exception: KVM handler can set the HSRR trap bit Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 10/52] powerpc/64s/exception: Make EXCEPTION_PROLOG_0 a gas macro for consistency with others Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 11/52] powerpc/64s/exception: Move EXCEPTION_COMMON handler and return branches into callers Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 12/52] powerpc/64s/exception: Move EXCEPTION_COMMON additions " Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 13/52] powerpc/64s/exception: unwind exception-64s.h macros Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 14/52] powerpc/64s/exception: improve 0x500 handler code Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 15/52] powerpc/64s/exception: move EXCEPTION_PROLOG_2* to a more logical place Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 16/52] powerpc/64s/exception: remove STD_EXCEPTION_COMMON variants Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 17/52] powerpc/64s/exception: move KVM related code together Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 18/52] powerpc/64s/exception: move exception-64s.h code to exception-64s.S where it is used Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 19/52] powerpc/64s/exception: move head-64.h " Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 20/52] powerpc/64s/exception: remove __BRANCH_TO_KVM Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 21/52] powerpc/64s/exception: remove unused BRANCH_TO_COMMON Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 22/52] powerpc/64s/exception: use a gas macro for system call handler code Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 23/52] powerpc/64s/exception: fix indenting irregularities Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 24/52] powerpc/64s/exception: generate regs clear instructions using .rept Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 25/52] powerpc/64s/exception: remove bad stack branch Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 26/52] powerpc/64s/exception: remove pointless EXCEPTION_PROLOG macro indirection Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 27/52] powerpc/64s/exception: move paca save area offsets into exception-64s.S Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 28/52] powerpc/64s/exception: clean up system call entry Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 29/52] powerpc/64s/exception: avoid SPR RAW scoreboard stall in real mode entry Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 30/52] powerpc/64s/exception: optimise system_reset for idle, clean up non-idle case Nicholas Piggin
2019-06-20 5:41 ` Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 31/52] powerpc/64s/exception: mtmsrd L=1 cleanup Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 32/52] powerpc/64s/exception: windup use r9 consistently to restore SPRs Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 33/52] powerpc/64s/exception: move machine check windup in_mce handling Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 34/52] powerpc/64s/exception: simplify hmi windup code Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 35/52] powerpc/64s/exception: shuffle windup code around Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 36/52] powerpc/64s/exception: use common macro for windup Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 37/52] powerpc/64s/exception: add dar and dsisr options to exception macro Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 38/52] powerpc/64s/exception: machine check use standard macros to save dar/dsisr Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 39/52] powerpc/64s/exception: denorm handler use standard scratch save macro Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 40/52] powerpc/64s/exception: move SET_SCRATCH0 into EXCEPTION_PROLOG_0 Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 41/52] powerpc/tm: update comment about interrupt re-entrancy Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 42/52] powerpc/64s/exception: machine check fwnmi does not trigger when in HV mode Nicholas Piggin
2019-06-20 9:26 ` Mahesh Jagannath Salgaonkar
2019-06-20 9:50 ` Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 43/52] powerpc/64s/exception: machine check early only runs " Nicholas Piggin
2019-06-20 9:53 ` Mahesh J Salgaonkar
2019-06-20 10:16 ` Nicholas Piggin
2019-06-20 10:57 ` Mahesh Jagannath Salgaonkar
2019-06-20 5:14 ` [PATCH v2 44/52] powerpc/64s/exception: separate pseries and powernv mce delivery paths Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 45/52] powerpc/64s/exception: machine check windup restore cfar for host delivery Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 46/52] powerpc/64s/exception: fix machine check early should not set AMR Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 47/52] powerpc/64s/exception: machine check restructure handler to be more regular Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 48/52] powerpc/64s/exception: simplify machine check early path Nicholas Piggin
2019-06-20 5:14 ` Nicholas Piggin [this message]
2019-06-20 5:14 ` [PATCH v2 50/52] powerpc/64s/exception: untangle early machine check handler Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 51/52] powerpc/64s/exception: machine check improve branch labels Nicholas Piggin
2019-06-20 5:14 ` [PATCH v2 52/52] powerpc/64s/exception: add missing branch to self after RFI Nicholas Piggin
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