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-rw-r--r--arch/powerpc/kernel/exceptions-64s.S353
1 files changed, 214 insertions, 139 deletions
diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S
index eaf1f72131a1..651c36b056bd 100644
--- a/arch/powerpc/kernel/exceptions-64s.S
+++ b/arch/powerpc/kernel/exceptions-64s.S
@@ -48,7 +48,7 @@
.balign IFETCH_ALIGN_BYTES; \
.global name; \
_ASM_NOKPROBE_SYMBOL(name); \
- DEFINE_FIXED_SYMBOL(name); \
+ DEFINE_FIXED_SYMBOL(name, text); \
name:
#define TRAMP_REAL_BEGIN(name) \
@@ -76,31 +76,18 @@ name:
ld reg,PACAKBASE(r13); /* get high part of &label */ \
ori reg,reg,FIXED_SYMBOL_ABS_ADDR(label)
-#define __LOAD_HANDLER(reg, label) \
+#define __LOAD_HANDLER(reg, label, section) \
ld reg,PACAKBASE(r13); \
- ori reg,reg,(ABS_ADDR(label))@l
+ ori reg,reg,(ABS_ADDR(label, section))@l
/*
* Branches from unrelocated code (e.g., interrupts) to labels outside
* head-y require >64K offsets.
*/
-#define __LOAD_FAR_HANDLER(reg, label) \
+#define __LOAD_FAR_HANDLER(reg, label, section) \
ld reg,PACAKBASE(r13); \
- ori reg,reg,(ABS_ADDR(label))@l; \
- addis reg,reg,(ABS_ADDR(label))@h
-
-/*
- * Branch to label using its 0xC000 address. This results in instruction
- * address suitable for MSR[IR]=0 or 1, which allows relocation to be turned
- * on using mtmsr rather than rfid.
- *
- * This could set the 0xc bits for !RELOCATABLE as an immediate, rather than
- * load KBASE for a slight optimisation.
- */
-#define BRANCH_TO_C000(reg, label) \
- __LOAD_FAR_HANDLER(reg, label); \
- mtctr reg; \
- bctr
+ ori reg,reg,(ABS_ADDR(label, section))@l; \
+ addis reg,reg,(ABS_ADDR(label, section))@h
/*
* Interrupt code generation macros
@@ -111,9 +98,10 @@ name:
#define IAREA .L_IAREA_\name\() /* PACA save area */
#define IVIRT .L_IVIRT_\name\() /* Has virt mode entry point */
#define IISIDE .L_IISIDE_\name\() /* Uses SRR0/1 not DAR/DSISR */
+#define ICFAR .L_ICFAR_\name\() /* Uses CFAR */
+#define ICFAR_IF_HVMODE .L_ICFAR_IF_HVMODE_\name\() /* Uses CFAR if HV */
#define IDAR .L_IDAR_\name\() /* Uses DAR (or SRR0) */
#define IDSISR .L_IDSISR_\name\() /* Uses DSISR (or SRR1) */
-#define ISET_RI .L_ISET_RI_\name\() /* Run common code w/ MSR[RI]=1 */
#define IBRANCH_TO_COMMON .L_IBRANCH_TO_COMMON_\name\() /* ENTRY branch to common */
#define IREALMODE_COMMON .L_IREALMODE_COMMON_\name\() /* Common runs in realmode */
#define IMASK .L_IMASK_\name\() /* IRQ soft-mask bit */
@@ -151,15 +139,18 @@ do_define_int n
.ifndef IISIDE
IISIDE=0
.endif
+ .ifndef ICFAR
+ ICFAR=1
+ .endif
+ .ifndef ICFAR_IF_HVMODE
+ ICFAR_IF_HVMODE=0
+ .endif
.ifndef IDAR
IDAR=0
.endif
.ifndef IDSISR
IDSISR=0
.endif
- .ifndef ISET_RI
- ISET_RI=1
- .endif
.ifndef IBRANCH_TO_COMMON
IBRANCH_TO_COMMON=1
.endif
@@ -290,10 +281,22 @@ BEGIN_FTR_SECTION
mfspr r9,SPRN_PPR
END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
HMT_MEDIUM
- std r10,IAREA+EX_R10(r13) /* save r10 - r12 */
+ std r10,IAREA+EX_R10(r13) /* save r10 */
+ .if ICFAR
BEGIN_FTR_SECTION
mfspr r10,SPRN_CFAR
END_FTR_SECTION_IFSET(CPU_FTR_CFAR)
+ .elseif ICFAR_IF_HVMODE
+BEGIN_FTR_SECTION
+ BEGIN_FTR_SECTION_NESTED(69)
+ mfspr r10,SPRN_CFAR
+ END_FTR_SECTION_NESTED(CPU_FTR_CFAR, CPU_FTR_CFAR, 69)
+FTR_SECTION_ELSE
+ BEGIN_FTR_SECTION_NESTED(69)
+ li r10,0
+ END_FTR_SECTION_NESTED(CPU_FTR_CFAR, CPU_FTR_CFAR, 69)
+ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)
+ .endif
.if \ool
.if !\virt
b tramp_real_\name
@@ -309,14 +312,16 @@ END_FTR_SECTION_IFSET(CPU_FTR_CFAR)
BEGIN_FTR_SECTION
std r9,IAREA+EX_PPR(r13)
END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
+ .if ICFAR || ICFAR_IF_HVMODE
BEGIN_FTR_SECTION
std r10,IAREA+EX_CFAR(r13)
END_FTR_SECTION_IFSET(CPU_FTR_CFAR)
+ .endif
INTERRUPT_TO_KERNEL
mfctr r10
std r10,IAREA+EX_CTR(r13)
mfcr r9
- std r11,IAREA+EX_R11(r13)
+ std r11,IAREA+EX_R11(r13) /* save r11 - r12 */
std r12,IAREA+EX_R12(r13)
/*
@@ -376,7 +381,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_CFAR)
* This switches to virtual mode and sets MSR[RI].
*/
.macro __GEN_COMMON_ENTRY name
-DEFINE_FIXED_SYMBOL(\name\()_common_real)
+DEFINE_FIXED_SYMBOL(\name\()_common_real, text)
\name\()_common_real:
.if IKVM_REAL
KVMTEST \name kvm_interrupt
@@ -399,7 +404,7 @@ DEFINE_FIXED_SYMBOL(\name\()_common_real)
.endif
.balign IFETCH_ALIGN_BYTES
-DEFINE_FIXED_SYMBOL(\name\()_common_virt)
+DEFINE_FIXED_SYMBOL(\name\()_common_virt, text)
\name\()_common_virt:
.if IKVM_VIRT
KVMTEST \name kvm_interrupt
@@ -413,7 +418,7 @@ DEFINE_FIXED_SYMBOL(\name\()_common_virt)
* want to run in real mode.
*/
.macro __GEN_REALMODE_COMMON_ENTRY name
-DEFINE_FIXED_SYMBOL(\name\()_common_real)
+DEFINE_FIXED_SYMBOL(\name\()_common_real, text)
\name\()_common_real:
.if IKVM_REAL
KVMTEST \name kvm_interrupt
@@ -512,11 +517,6 @@ DEFINE_FIXED_SYMBOL(\name\()_common_real)
stb r10,PACASRR_VALID(r13)
.endif
- .if ISET_RI
- li r10,MSR_RI
- mtmsrd r10,1 /* Set MSR_RI */
- .endif
-
.if ISTACK
.if IKUAP
kuap_save_amr_and_lock r9, r10, cr1, cr0
@@ -568,16 +568,19 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
.endif
BEGIN_FTR_SECTION
+ .if ICFAR || ICFAR_IF_HVMODE
ld r10,IAREA+EX_CFAR(r13)
+ .else
+ li r10,0
+ .endif
std r10,ORIG_GPR3(r1)
END_FTR_SECTION_IFSET(CPU_FTR_CFAR)
ld r10,IAREA+EX_CTR(r13)
std r10,_CTR(r1)
std r2,GPR2(r1) /* save r2 in stackframe */
- SAVE_4GPRS(3, r1) /* save r3 - r6 in stackframe */
- SAVE_2GPRS(7, r1) /* save r7, r8 in stackframe */
+ SAVE_GPRS(3, 8, r1) /* save r3 - r8 in stackframe */
mflr r9 /* Get LR, later save to stack */
- ld r2,PACATOC(r13) /* get kernel TOC into r2 */
+ LOAD_PACA_TOC() /* get kernel TOC into r2 */
std r9,_LINK(r1)
lbz r10,PACAIRQSOFTMASK(r13)
mfspr r11,SPRN_XER /* save XER in stackframe */
@@ -586,7 +589,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_CFAR)
li r9,IVEC
std r9,_TRAP(r1) /* set trap number */
li r10,0
- ld r11,exception_marker@toc(r2)
+ LOAD_REG_IMMEDIATE(r11, STACK_FRAME_REGS_MARKER)
std r10,RESULT(r1) /* clear regs->result */
std r11,STACK_FRAME_OVERHEAD-16(r1) /* mark the frame */
.endm
@@ -607,7 +610,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_CFAR)
.macro SEARCH_RESTART_TABLE
#ifdef CONFIG_RELOCATABLE
mr r12,r2
- ld r2,PACATOC(r13)
+ LOAD_PACA_TOC()
LOAD_REG_ADDR(r9, __start___restart_table)
LOAD_REG_ADDR(r10, __stop___restart_table)
mr r2,r12
@@ -637,7 +640,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_CFAR)
.macro SEARCH_SOFT_MASK_TABLE
#ifdef CONFIG_RELOCATABLE
mr r12,r2
- ld r2,PACATOC(r13)
+ LOAD_PACA_TOC()
LOAD_REG_ADDR(r9, __start___soft_mask_table)
LOAD_REG_ADDR(r10, __stop___soft_mask_table)
mr r2,r12
@@ -693,14 +696,78 @@ END_FTR_SECTION_IFSET(CPU_FTR_CFAR)
mtlr r9
ld r9,_CCR(r1)
mtcr r9
- REST_8GPRS(2, r1)
- REST_4GPRS(10, r1)
+ REST_GPRS(2, 13, r1)
REST_GPR(0, r1)
/* restore original r1. */
ld r1,GPR1(r1)
.endm
/*
+ * EARLY_BOOT_FIXUP - Fix real-mode interrupt with wrong endian in early boot.
+ *
+ * There's a short window during boot where although the kernel is running
+ * little endian, any exceptions will cause the CPU to switch back to big
+ * endian. For example a WARN() boils down to a trap instruction, which will
+ * cause a program check, and we end up here but with the CPU in big endian
+ * mode. The first instruction of the program check handler (in GEN_INT_ENTRY
+ * below) is an mtsprg, which when executed in the wrong endian is an lhzu with
+ * a ~3GB displacement from r3. The content of r3 is random, so that is a load
+ * from some random location, and depending on the system can easily lead to a
+ * checkstop, or an infinitely recursive page fault.
+ *
+ * So to handle that case we have a trampoline here that can detect we are in
+ * the wrong endian and flip us back to the correct endian. We can't flip
+ * MSR[LE] using mtmsr, so we have to use rfid. That requires backing up SRR0/1
+ * as well as a GPR. To do that we use SPRG0/2/3, as SPRG1 is already used for
+ * the paca. SPRG3 is user readable, but this trampoline is only active very
+ * early in boot, and SPRG3 will be reinitialised in vdso_getcpu_init() before
+ * userspace starts.
+ */
+.macro EARLY_BOOT_FIXUP
+BEGIN_FTR_SECTION
+#ifdef CONFIG_CPU_LITTLE_ENDIAN
+ tdi 0,0,0x48 // Trap never, or in reverse endian: b . + 8
+ b 2f // Skip trampoline if endian is correct
+ .long 0xa643707d // mtsprg 0, r11 Backup r11
+ .long 0xa6027a7d // mfsrr0 r11
+ .long 0xa643727d // mtsprg 2, r11 Backup SRR0 in SPRG2
+ .long 0xa6027b7d // mfsrr1 r11
+ .long 0xa643737d // mtsprg 3, r11 Backup SRR1 in SPRG3
+ .long 0xa600607d // mfmsr r11
+ .long 0x01006b69 // xori r11, r11, 1 Invert MSR[LE]
+ .long 0xa6037b7d // mtsrr1 r11
+ /*
+ * This is 'li r11,1f' where 1f is the absolute address of that
+ * label, byteswapped into the SI field of the instruction.
+ */
+ .long 0x00006039 | \
+ ((ABS_ADDR(1f, real_vectors) & 0x00ff) << 24) | \
+ ((ABS_ADDR(1f, real_vectors) & 0xff00) << 8)
+ .long 0xa6037a7d // mtsrr0 r11
+ .long 0x2400004c // rfid
+1:
+ mfsprg r11, 3
+ mtsrr1 r11 // Restore SRR1
+ mfsprg r11, 2
+ mtsrr0 r11 // Restore SRR0
+ mfsprg r11, 0 // Restore r11
+2:
+#endif
+ /*
+ * program check could hit at any time, and pseries can not block
+ * MSR[ME] in early boot. So check if there is anything useful in r13
+ * yet, and spin forever if not.
+ */
+ mtsprg 0, r11
+ mfcr r11
+ cmpdi r13, 0
+ beq .
+ mtcr r11
+ mfsprg r11, 0
+END_FTR_SECTION(0, 1) // nop out after boot
+.endm
+
+/*
* There are a few constraints to be concerned with.
* - Real mode exceptions code/data must be located at their physical location.
* - Virtual mode exceptions must be mapped at their 0xc000... location.
@@ -807,6 +874,10 @@ __start_interrupts:
* - MSR_EE|MSR_RI is clear (no reentrant exceptions)
* - Standard kernel environment is set up (stack, paca, etc)
*
+ * KVM:
+ * These interrupts do not elevate HV 0->1, so HV is not involved. PR KVM
+ * ensures that FSCR[SCV] is disabled whenever it has to force AIL off.
+ *
* Call convention:
*
* syscall register convention is in Documentation/powerpc/syscall64-abi.rst
@@ -850,12 +921,12 @@ SOFT_MASK_TABLE(0xc000000000003000, 0xc000000000004000)
#ifdef CONFIG_RELOCATABLE
TRAMP_VIRT_BEGIN(system_call_vectored_tramp)
- __LOAD_HANDLER(r10, system_call_vectored_common)
+ __LOAD_HANDLER(r10, system_call_vectored_common, virt_trampolines)
mtctr r10
bctr
TRAMP_VIRT_BEGIN(system_call_vectored_sigill_tramp)
- __LOAD_HANDLER(r10, system_call_vectored_sigill)
+ __LOAD_HANDLER(r10, system_call_vectored_sigill, virt_trampolines)
mtctr r10
bctr
#endif
@@ -902,11 +973,6 @@ INT_DEFINE_BEGIN(system_reset)
IVEC=0x100
IAREA=PACA_EXNMI
IVIRT=0 /* no virt entry point */
- /*
- * MSR_RI is not enabled, because PACA_EXNMI and nmi stack is
- * being used, so a nested NMI exception would corrupt it.
- */
- ISET_RI=0
ISTACK=0
IKVM_REAL=1
INT_DEFINE_END(system_reset)
@@ -964,7 +1030,9 @@ TRAMP_REAL_BEGIN(system_reset_idle_wake)
/* We are waking up from idle, so may clobber any volatile register */
cmpwi cr1,r5,2
bltlr cr1 /* no state loss, return to idle caller with r3=SRR1 */
- BRANCH_TO_C000(r12, DOTSYM(idle_return_gpr_loss))
+ __LOAD_FAR_HANDLER(r12, DOTSYM(idle_return_gpr_loss), real_trampolines)
+ mtctr r12
+ bctr
#endif
#ifdef CONFIG_PPC_PSERIES
@@ -979,16 +1047,14 @@ TRAMP_REAL_BEGIN(system_reset_fwnmi)
EXC_COMMON_BEGIN(system_reset_common)
__GEN_COMMON_ENTRY system_reset
/*
- * Increment paca->in_nmi then enable MSR_RI. SLB or MCE will be able
- * to recover, but nested NMI will notice in_nmi and not recover
- * because of the use of the NMI stack. in_nmi reentrancy is tested in
- * system_reset_exception.
+ * Increment paca->in_nmi. When the interrupt entry wrapper later
+ * enable MSR_RI, then SLB or MCE will be able to recover, but a nested
+ * NMI will notice in_nmi and not recover because of the use of the NMI
+ * stack. in_nmi reentrancy is tested in system_reset_exception.
*/
lhz r10,PACA_IN_NMI(r13)
addi r10,r10,1
sth r10,PACA_IN_NMI(r13)
- li r10,MSR_RI
- mtmsrd r10,1
mr r10,r1
ld r1,PACA_NMI_EMERG_SP(r13)
@@ -1062,12 +1128,6 @@ INT_DEFINE_BEGIN(machine_check_early)
IAREA=PACA_EXMC
IVIRT=0 /* no virt entry point */
IREALMODE_COMMON=1
- /*
- * MSR_RI is not enabled, because PACA_EXMC is being used, so a
- * nested machine check corrupts it. machine_check_common enables
- * MSR_RI.
- */
- ISET_RI=0
ISTACK=0
IDAR=1
IDSISR=1
@@ -1078,13 +1138,13 @@ INT_DEFINE_BEGIN(machine_check)
IVEC=0x200
IAREA=PACA_EXMC
IVIRT=0 /* no virt entry point */
- ISET_RI=0
IDAR=1
IDSISR=1
IKVM_REAL=1
INT_DEFINE_END(machine_check)
EXC_REAL_BEGIN(machine_check, 0x200, 0x100)
+ EARLY_BOOT_FIXUP
GEN_INT_ENTRY machine_check_early, virt=0
EXC_REAL_END(machine_check, 0x200, 0x100)
EXC_VIRT_NONE(0x4200, 0x100)
@@ -1148,10 +1208,10 @@ EXC_COMMON_BEGIN(machine_check_early_common)
BEGIN_FTR_SECTION
bl enable_machine_check
END_FTR_SECTION_IFSET(CPU_FTR_HVMODE)
- li r10,MSR_RI
- mtmsrd r10,1
-
addi r3,r1,STACK_FRAME_OVERHEAD
+BEGIN_FTR_SECTION
+ bl machine_check_early_boot
+END_FTR_SECTION(0, 1) // nop out after boot
bl machine_check_early
std r3,RESULT(r1) /* Save result */
ld r12,_MSR(r1)
@@ -1238,10 +1298,6 @@ EXC_COMMON_BEGIN(machine_check_common)
* save area: PACA_EXMC instead of PACA_EXGEN.
*/
GEN_COMMON machine_check
-
- /* Enable MSR_RI when finished with PACA_EXMC */
- li r10,MSR_RI
- mtmsrd r10,1
addi r3,r1,STACK_FRAME_OVERHEAD
bl machine_check_exception_async
b interrupt_return_srr
@@ -1369,11 +1425,15 @@ EXC_COMMON_BEGIN(data_access_common)
addi r3,r1,STACK_FRAME_OVERHEAD
andis. r0,r4,DSISR_DABRMATCH@h
bne- 1f
+#ifdef CONFIG_PPC_64S_HASH_MMU
BEGIN_MMU_FTR_SECTION
bl do_hash_fault
MMU_FTR_SECTION_ELSE
bl do_page_fault
ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_TYPE_RADIX)
+#else
+ bl do_page_fault
+#endif
b interrupt_return_srr
1: bl do_break
@@ -1416,6 +1476,7 @@ EXC_VIRT_BEGIN(data_access_slb, 0x4380, 0x80)
EXC_VIRT_END(data_access_slb, 0x4380, 0x80)
EXC_COMMON_BEGIN(data_access_slb_common)
GEN_COMMON data_access_slb
+#ifdef CONFIG_PPC_64S_HASH_MMU
BEGIN_MMU_FTR_SECTION
/* HPT case, do SLB fault */
addi r3,r1,STACK_FRAME_OVERHEAD
@@ -1428,9 +1489,12 @@ MMU_FTR_SECTION_ELSE
/* Radix case, access is outside page table range */
li r3,-EFAULT
ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_TYPE_RADIX)
+#else
+ li r3,-EFAULT
+#endif
std r3,RESULT(r1)
addi r3,r1,STACK_FRAME_OVERHEAD
- bl do_bad_slb_fault
+ bl do_bad_segment_interrupt
b interrupt_return_srr
@@ -1462,11 +1526,15 @@ EXC_VIRT_END(instruction_access, 0x4400, 0x80)
EXC_COMMON_BEGIN(instruction_access_common)
GEN_COMMON instruction_access
addi r3,r1,STACK_FRAME_OVERHEAD
+#ifdef CONFIG_PPC_64S_HASH_MMU
BEGIN_MMU_FTR_SECTION
bl do_hash_fault
MMU_FTR_SECTION_ELSE
bl do_page_fault
ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_TYPE_RADIX)
+#else
+ bl do_page_fault
+#endif
b interrupt_return_srr
@@ -1496,6 +1564,7 @@ EXC_VIRT_BEGIN(instruction_access_slb, 0x4480, 0x80)
EXC_VIRT_END(instruction_access_slb, 0x4480, 0x80)
EXC_COMMON_BEGIN(instruction_access_slb_common)
GEN_COMMON instruction_access_slb
+#ifdef CONFIG_PPC_64S_HASH_MMU
BEGIN_MMU_FTR_SECTION
/* HPT case, do SLB fault */
addi r3,r1,STACK_FRAME_OVERHEAD
@@ -1508,9 +1577,12 @@ MMU_FTR_SECTION_ELSE
/* Radix case, access is outside page table range */
li r3,-EFAULT
ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_TYPE_RADIX)
+#else
+ li r3,-EFAULT
+#endif
std r3,RESULT(r1)
addi r3,r1,STACK_FRAME_OVERHEAD
- bl do_bad_slb_fault
+ bl do_bad_segment_interrupt
b interrupt_return_srr
@@ -1536,6 +1608,12 @@ ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_TYPE_RADIX)
*
* If soft masked, the masked handler will note the pending interrupt for
* replay, and clear MSR[EE] in the interrupted context.
+ *
+ * CFAR is not required because this is an asynchronous interrupt that in
+ * general won't have much bearing on the state of the CPU, with the possible
+ * exception of crash/debug IPIs, but those are generally moving to use SRESET
+ * IPIs. Unless this is an HV interrupt and KVM HV is possible, in which case
+ * it may be exiting the guest and need CFAR to be saved.
*/
INT_DEFINE_BEGIN(hardware_interrupt)
IVEC=0x500
@@ -1543,6 +1621,10 @@ INT_DEFINE_BEGIN(hardware_interrupt)
IMASK=IRQS_DISABLED
IKVM_REAL=1
IKVM_VIRT=1
+ ICFAR=0
+#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
+ ICFAR_IF_HVMODE=1
+#endif
INT_DEFINE_END(hardware_interrupt)
EXC_REAL_BEGIN(hardware_interrupt, 0x500, 0x100)
@@ -1606,51 +1688,7 @@ INT_DEFINE_BEGIN(program_check)
INT_DEFINE_END(program_check)
EXC_REAL_BEGIN(program_check, 0x700, 0x100)
-
-#ifdef CONFIG_CPU_LITTLE_ENDIAN
- /*
- * There's a short window during boot where although the kernel is
- * running little endian, any exceptions will cause the CPU to switch
- * back to big endian. For example a WARN() boils down to a trap
- * instruction, which will cause a program check, and we end up here but
- * with the CPU in big endian mode. The first instruction of the program
- * check handler (in GEN_INT_ENTRY below) is an mtsprg, which when
- * executed in the wrong endian is an lhzu with a ~3GB displacement from
- * r3. The content of r3 is random, so that is a load from some random
- * location, and depending on the system can easily lead to a checkstop,
- * or an infinitely recursive page fault.
- *
- * So to handle that case we have a trampoline here that can detect we
- * are in the wrong endian and flip us back to the correct endian. We
- * can't flip MSR[LE] using mtmsr, so we have to use rfid. That requires
- * backing up SRR0/1 as well as a GPR. To do that we use SPRG0/2/3, as
- * SPRG1 is already used for the paca. SPRG3 is user readable, but this
- * trampoline is only active very early in boot, and SPRG3 will be
- * reinitialised in vdso_getcpu_init() before userspace starts.
- */
-BEGIN_FTR_SECTION
- tdi 0,0,0x48 // Trap never, or in reverse endian: b . + 8
- b 1f // Skip trampoline if endian is correct
- .long 0xa643707d // mtsprg 0, r11 Backup r11
- .long 0xa6027a7d // mfsrr0 r11
- .long 0xa643727d // mtsprg 2, r11 Backup SRR0 in SPRG2
- .long 0xa6027b7d // mfsrr1 r11
- .long 0xa643737d // mtsprg 3, r11 Backup SRR1 in SPRG3
- .long 0xa600607d // mfmsr r11
- .long 0x01006b69 // xori r11, r11, 1 Invert MSR[LE]
- .long 0xa6037b7d // mtsrr1 r11
- .long 0x34076039 // li r11, 0x734
- .long 0xa6037a7d // mtsrr0 r11
- .long 0x2400004c // rfid
- mfsprg r11, 3
- mtsrr1 r11 // Restore SRR1
- mfsprg r11, 2
- mtsrr0 r11 // Restore SRR0
- mfsprg r11, 0 // Restore r11
-1:
-END_FTR_SECTION(0, 1) // nop out after boot
-#endif /* CONFIG_CPU_LITTLE_ENDIAN */
-
+ EARLY_BOOT_FIXUP
GEN_INT_ENTRY program_check, virt=0
EXC_REAL_END(program_check, 0x700, 0x100)
EXC_VIRT_BEGIN(program_check, 0x4700, 0x100)
@@ -1764,6 +1802,10 @@ END_FTR_SECTION_IFSET(CPU_FTR_TM)
* If PPC_WATCHDOG is configured, the soft masked handler will actually set
* things back up to run soft_nmi_interrupt as a regular interrupt handler
* on the emergency stack.
+ *
+ * CFAR is not required because this is asynchronous (see hardware_interrupt).
+ * A watchdog interrupt may like to have CFAR, but usually the interesting
+ * branch is long gone by that point (e.g., infinite loop).
*/
INT_DEFINE_BEGIN(decrementer)
IVEC=0x900
@@ -1771,6 +1813,7 @@ INT_DEFINE_BEGIN(decrementer)
#ifdef CONFIG_KVM_BOOK3S_PR_POSSIBLE
IKVM_REAL=1
#endif
+ ICFAR=0
INT_DEFINE_END(decrementer)
EXC_REAL_BEGIN(decrementer, 0x900, 0x80)
@@ -1846,6 +1889,8 @@ EXC_COMMON_BEGIN(hdecrementer_common)
* If soft masked, the masked handler will note the pending interrupt for
* replay, leaving MSR[EE] enabled in the interrupted context because the
* doorbells are edge triggered.
+ *
+ * CFAR is not required, similarly to hardware_interrupt.
*/
INT_DEFINE_BEGIN(doorbell_super)
IVEC=0xa00
@@ -1853,6 +1898,7 @@ INT_DEFINE_BEGIN(doorbell_super)
#ifdef CONFIG_KVM_BOOK3S_PR_POSSIBLE
IKVM_REAL=1
#endif
+ ICFAR=0
INT_DEFINE_END(doorbell_super)
EXC_REAL_BEGIN(doorbell_super, 0xa00, 0x100)
@@ -1904,6 +1950,7 @@ INT_DEFINE_BEGIN(system_call)
IVEC=0xc00
IKVM_REAL=1
IKVM_VIRT=1
+ ICFAR=0
INT_DEFINE_END(system_call)
.macro SYSTEM_CALL virt
@@ -1942,12 +1989,12 @@ END_FTR_SECTION_IFSET(CPU_FTR_REAL_LE)
HMT_MEDIUM
.if ! \virt
- __LOAD_HANDLER(r10, system_call_common_real)
+ __LOAD_HANDLER(r10, system_call_common_real, real_vectors)
mtctr r10
bctr
.else
#ifdef CONFIG_RELOCATABLE
- __LOAD_HANDLER(r10, system_call_common)
+ __LOAD_HANDLER(r10, system_call_common, virt_vectors)
mtctr r10
bctr
#else
@@ -2001,7 +2048,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
* Requires __LOAD_FAR_HANDLER beause kvmppc_hcall lives
* outside the head section.
*/
- __LOAD_FAR_HANDLER(r10, kvmppc_hcall)
+ __LOAD_FAR_HANDLER(r10, kvmppc_hcall, real_trampolines)
mtctr r10
bctr
#else
@@ -2202,6 +2249,11 @@ EXC_COMMON_BEGIN(hmi_exception_common)
* Interrupt 0xe80 - Directed Hypervisor Doorbell Interrupt.
* This is an asynchronous interrupt in response to a msgsnd doorbell.
* Similar to the 0xa00 doorbell but for host rather than guest.
+ *
+ * CFAR is not required (similar to doorbell_interrupt), unless KVM HV
+ * is enabled, in which case it may be a guest exit. Most PowerNV kernels
+ * include KVM support so it would be nice if this could be dynamically
+ * patched out if KVM was not currently running any guests.
*/
INT_DEFINE_BEGIN(h_doorbell)
IVEC=0xe80
@@ -2209,6 +2261,9 @@ INT_DEFINE_BEGIN(h_doorbell)
IMASK=IRQS_DISABLED
IKVM_REAL=1
IKVM_VIRT=1
+#ifndef CONFIG_KVM_BOOK3S_HV_POSSIBLE
+ ICFAR=0
+#endif
INT_DEFINE_END(h_doorbell)
EXC_REAL_BEGIN(h_doorbell, 0xe80, 0x20)
@@ -2232,6 +2287,9 @@ EXC_COMMON_BEGIN(h_doorbell_common)
* Interrupt 0xea0 - Hypervisor Virtualization Interrupt.
* This is an asynchronous interrupt in response to an "external exception".
* Similar to 0x500 but for host only.
+ *
+ * Like h_doorbell, CFAR is only required for KVM HV because this can be
+ * a guest exit.
*/
INT_DEFINE_BEGIN(h_virt_irq)
IVEC=0xea0
@@ -2239,6 +2297,9 @@ INT_DEFINE_BEGIN(h_virt_irq)
IMASK=IRQS_DISABLED
IKVM_REAL=1
IKVM_VIRT=1
+#ifndef CONFIG_KVM_BOOK3S_HV_POSSIBLE
+ ICFAR=0
+#endif
INT_DEFINE_END(h_virt_irq)
EXC_REAL_BEGIN(h_virt_irq, 0xea0, 0x20)
@@ -2275,6 +2336,8 @@ EXC_VIRT_NONE(0x4ee0, 0x20)
*
* If soft masked, the masked handler will note the pending interrupt for
* replay, and clear MSR[EE] in the interrupted context.
+ *
+ * CFAR is not used by perf interrupts so not required.
*/
INT_DEFINE_BEGIN(performance_monitor)
IVEC=0xf00
@@ -2282,6 +2345,7 @@ INT_DEFINE_BEGIN(performance_monitor)
#ifdef CONFIG_KVM_BOOK3S_PR_POSSIBLE
IKVM_REAL=1
#endif
+ ICFAR=0
INT_DEFINE_END(performance_monitor)
EXC_REAL_BEGIN(performance_monitor, 0xf00, 0x20)
@@ -2293,9 +2357,21 @@ EXC_VIRT_END(performance_monitor, 0x4f00, 0x20)
EXC_COMMON_BEGIN(performance_monitor_common)
GEN_COMMON performance_monitor
addi r3,r1,STACK_FRAME_OVERHEAD
- bl performance_monitor_exception
+ lbz r4,PACAIRQSOFTMASK(r13)
+ cmpdi r4,IRQS_ENABLED
+ bne 1f
+ bl performance_monitor_exception_async
b interrupt_return_srr
+1:
+ bl performance_monitor_exception_nmi
+ /* Clear MSR_RI before setting SRR0 and SRR1. */
+ li r9,0
+ mtmsrd r9,1
+
+ kuap_kernel_restore r9, r10
+ EXCEPTION_RESTORE_REGS hsrr=0
+ RFI_TO_KERNEL
/**
* Interrupt 0xf20 - Vector Unavailable Interrupt.
@@ -2706,6 +2782,7 @@ EXC_VIRT_NONE(0x5800, 0x100)
INT_DEFINE_BEGIN(soft_nmi)
IVEC=0x900
ISTACK=0
+ ICFAR=0
INT_DEFINE_END(soft_nmi)
/*
@@ -2739,7 +2816,7 @@ EXC_COMMON_BEGIN(soft_nmi_common)
/*
* An interrupt came in while soft-disabled. We set paca->irq_happened, then:
- * - If it was a decrementer interrupt, we bump the dec to max and and return.
+ * - If it was a decrementer interrupt, we bump the dec to max and return.
* - If it was a doorbell we return immediately since doorbells are edge
* triggered and won't automatically refire.
* - If it was a HMI we return immediately since we handled it in realmode
@@ -2754,6 +2831,20 @@ masked_Hinterrupt:
masked_interrupt:
.endif
stw r9,PACA_EXGEN+EX_CCR(r13)
+#ifdef CONFIG_PPC_IRQ_SOFT_MASK_DEBUG
+ /*
+ * Ensure there was no previous MUST_HARD_MASK interrupt or
+ * HARD_DIS setting. If this does fire, the interrupt is still
+ * masked and MSR[EE] will be cleared on return, so no need to
+ * panic, but somebody probably enabled MSR[EE] under
+ * PACA_IRQ_HARD_DIS, mtmsr(mfmsr() | MSR_x) being a common
+ * cause.
+ */
+ lbz r9,PACAIRQHAPPENED(r13)
+ andi. r9,r9,(PACA_IRQ_MUST_HARD_MASK|PACA_IRQ_HARD_DIS)
+0: tdnei r9,0
+ EMIT_WARN_ENTRY 0b,__FILE__,__LINE__,(BUGFLAG_WARNING | BUGFLAG_ONCE)
+#endif
lbz r9,PACAIRQHAPPENED(r13)
or r9,r9,r10
stb r9,PACAIRQHAPPENED(r13)
@@ -2994,22 +3085,6 @@ EXPORT_SYMBOL(do_uaccess_flush)
MASKED_INTERRUPT
MASKED_INTERRUPT hsrr=1
- /*
- * Relocation-on interrupts: A subset of the interrupts can be delivered
- * with IR=1/DR=1, if AIL==2 and MSR.HV won't be changed by delivering
- * it. Addresses are the same as the original interrupt addresses, but
- * offset by 0xc000000000004000.
- * It's impossible to receive interrupts below 0x300 via this mechanism.
- * KVM: None of these traps are from the guest ; anything that escalated
- * to HV=1 from HV=0 is delivered via real mode handlers.
- */
-
- /*
- * This uses the standard macro, since the original 0x300 vector
- * only has extra guff for STAB-based processors -- which never
- * come here.
- */
-
USE_FIXED_SECTION(virt_trampolines)
/*
* All code below __end_soft_masked is treated as soft-masked. If
@@ -3025,7 +3100,7 @@ USE_FIXED_SECTION(virt_trampolines)
.align 7
.globl __end_interrupts
__end_interrupts:
-DEFINE_FIXED_SYMBOL(__end_interrupts)
+DEFINE_FIXED_SYMBOL(__end_interrupts, virt_trampolines)
CLOSE_FIXED_SECTION(real_vectors);
CLOSE_FIXED_SECTION(real_trampolines);
@@ -3035,7 +3110,7 @@ CLOSE_FIXED_SECTION(virt_trampolines);
USE_TEXT_SECTION()
/* MSR[RI] should be clear because this uses SRR[01] */
-enable_machine_check:
+_GLOBAL(enable_machine_check)
mflr r0
bcl 20,31,$+4
0: mflr r3