| Message ID | 20230112154548.163021-8-frankja@linux.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | s390x: Snippet fixes | expand |
On Thu, 12 Jan 2023 15:45:48 +0000 Janosch Frank <frankja@linux.ibm.com> wrote: > When we leave SIE due to an exception, we'll still have guest values > in registers 0 - 13 and that's not clearly portraied in our debug > prints. So let's fix that. > > Signed-off-by: Janosch Frank <frankja@linux.ibm.com> > --- > lib/s390x/interrupt.c | 46 ++++++++++++++++++++++++++++++++++++++----- > lib/s390x/sie.h | 2 ++ > s390x/cpu.S | 6 ++++-- > 3 files changed, 47 insertions(+), 7 deletions(-) > > diff --git a/lib/s390x/interrupt.c b/lib/s390x/interrupt.c > index dadb7415..ff47c2c2 100644 > --- a/lib/s390x/interrupt.c > +++ b/lib/s390x/interrupt.c > @@ -9,6 +9,7 @@ > */ > #include <libcflat.h> > #include <asm/barrier.h> > +#include <asm/asm-offsets.h> > #include <sclp.h> > #include <interrupt.h> > #include <sie.h> > @@ -188,9 +189,12 @@ static void print_storage_exception_information(void) > } > } > > -static void print_int_regs(struct stack_frame_int *stack) > +static void print_int_regs(struct stack_frame_int *stack, bool sie) > { > + struct kvm_s390_sie_block *sblk; > + > printf("\n"); > + printf("%s\n", sie ? "Guest registers:" : "Host registers:"); > printf("GPRS:\n"); > printf("%016lx %016lx %016lx %016lx\n", > stack->grs1[0], stack->grs1[1], stack->grs0[0], stack->grs0[1]); > @@ -198,24 +202,56 @@ static void print_int_regs(struct stack_frame_int *stack) > stack->grs0[2], stack->grs0[3], stack->grs0[4], stack->grs0[5]); > printf("%016lx %016lx %016lx %016lx\n", > stack->grs0[6], stack->grs0[7], stack->grs0[8], stack->grs0[9]); > - printf("%016lx %016lx %016lx %016lx\n", > - stack->grs0[10], stack->grs0[11], stack->grs0[12], stack->grs0[13]); > + > + if (sie) { > + sblk = (struct kvm_s390_sie_block *)stack->grs0[12]; > + printf("%016lx %016lx %016lx %016lx\n", > + stack->grs0[10], stack->grs0[11], sblk->gg14, sblk->gg15); > + } else { > + printf("%016lx %016lx %016lx %016lx\n", > + stack->grs0[10], stack->grs0[11], stack->grs0[12], stack->grs0[13]); > + } > + > printf("\n"); > } > > static void print_pgm_info(struct stack_frame_int *stack) > > { > - bool in_sie; > + bool in_sie, in_sie_gregs; > + struct vm_save_area *vregs; > > in_sie = (lowcore.pgm_old_psw.addr >= (uintptr_t)sie_entry && > lowcore.pgm_old_psw.addr <= (uintptr_t)sie_exit); > + in_sie_gregs = (lowcore.pgm_old_psw.addr >= (uintptr_t)sie_entry_gregs && > + lowcore.pgm_old_psw.addr <= (uintptr_t)sie_exit_gregs); can you explain why <= instead of < ? (I think I know why, but a comment would not hurt) with that fixed: Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com> > > printf("\n"); > printf("Unexpected program interrupt %s: %#x on cpu %d at %#lx, ilen %d\n", > in_sie ? "in SIE" : "", > lowcore.pgm_int_code, stap(), lowcore.pgm_old_psw.addr, lowcore.pgm_int_id); > - print_int_regs(stack); > + > + /* > + * If we fall out of SIE before loading the host registers, > + * then we need to do it here so we print the host registers > + * and not the guest registers. > + * > + * Back tracing is actually not a problem since SIE restores gr15. > + */ > + if (in_sie_gregs) { > + print_int_regs(stack, true); > + vregs = *((struct vm_save_area **)(stack->grs0[13] + __SF_SIE_SAVEAREA)); > + > + /* > + * The grs are not linear on the interrupt stack frame. > + * We copy 0 and 1 here and 2 - 15 with the memcopy below. > + */ > + stack->grs1[0] = vregs->host.grs[0]; > + stack->grs1[1] = vregs->host.grs[1]; > + /* 2 - 15 */ > + memcpy(stack->grs0, &vregs->host.grs[2], sizeof(stack->grs0) - 8); > + } > + print_int_regs(stack, false); > dump_stack(); > > /* Dump stack doesn't end with a \n so we add it here instead */ > diff --git a/lib/s390x/sie.h b/lib/s390x/sie.h > index a27a8401..147cb0f2 100644 > --- a/lib/s390x/sie.h > +++ b/lib/s390x/sie.h > @@ -273,6 +273,8 @@ struct vm { > > extern void sie_entry(void); > extern void sie_exit(void); > +extern void sie_entry_gregs(void); > +extern void sie_exit_gregs(void); > extern void sie64a(struct kvm_s390_sie_block *sblk, struct vm_save_area *save_area); > void sie(struct vm *vm); > void sie_expect_validity(struct vm *vm); > diff --git a/s390x/cpu.S b/s390x/cpu.S > index 45bd551a..9155b044 100644 > --- a/s390x/cpu.S > +++ b/s390x/cpu.S > @@ -82,7 +82,8 @@ sie64a: > # Store scb and save_area pointer into stack frame > stg %r2,__SF_SIE_CONTROL(%r15) # save control block pointer > stg %r3,__SF_SIE_SAVEAREA(%r15) # save guest register save area > - > +.globl sie_entry_gregs > +sie_entry_gregs: > # Load guest's gprs, fprs and fpc > .irp i, 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15 > ld \i, \i * 8 + SIE_SAVEAREA_GUEST_FPRS(%r3) > @@ -121,7 +122,8 @@ sie_exit: > .endr > lfpc SIE_SAVEAREA_HOST_FPC(%r14) > lmg %r0,%r14,SIE_SAVEAREA_HOST_GRS(%r14) # restore kernel registers > - > +.globl sie_exit_gregs > +sie_exit_gregs: > br %r14 > > .align 8
On 1/12/23 18:13, Claudio Imbrenda wrote: > On Thu, 12 Jan 2023 15:45:48 +0000 > Janosch Frank <frankja@linux.ibm.com> wrote: > >> When we leave SIE due to an exception, we'll still have guest values >> in registers 0 - 13 and that's not clearly portraied in our debug >> prints. So let's fix that. >> >> Signed-off-by: Janosch Frank <frankja@linux.ibm.com> >> --- >> lib/s390x/interrupt.c | 46 ++++++++++++++++++++++++++++++++++++++----- >> lib/s390x/sie.h | 2 ++ >> s390x/cpu.S | 6 ++++-- >> 3 files changed, 47 insertions(+), 7 deletions(-) >> >> diff --git a/lib/s390x/interrupt.c b/lib/s390x/interrupt.c >> index dadb7415..ff47c2c2 100644 >> --- a/lib/s390x/interrupt.c >> +++ b/lib/s390x/interrupt.c >> @@ -9,6 +9,7 @@ >> */ >> #include <libcflat.h> >> #include <asm/barrier.h> >> +#include <asm/asm-offsets.h> >> #include <sclp.h> >> #include <interrupt.h> >> #include <sie.h> >> @@ -188,9 +189,12 @@ static void print_storage_exception_information(void) >> } >> } >> >> -static void print_int_regs(struct stack_frame_int *stack) >> +static void print_int_regs(struct stack_frame_int *stack, bool sie) >> { >> + struct kvm_s390_sie_block *sblk; >> + >> printf("\n"); >> + printf("%s\n", sie ? "Guest registers:" : "Host registers:"); >> printf("GPRS:\n"); >> printf("%016lx %016lx %016lx %016lx\n", >> stack->grs1[0], stack->grs1[1], stack->grs0[0], stack->grs0[1]); >> @@ -198,24 +202,56 @@ static void print_int_regs(struct stack_frame_int *stack) >> stack->grs0[2], stack->grs0[3], stack->grs0[4], stack->grs0[5]); >> printf("%016lx %016lx %016lx %016lx\n", >> stack->grs0[6], stack->grs0[7], stack->grs0[8], stack->grs0[9]); >> - printf("%016lx %016lx %016lx %016lx\n", >> - stack->grs0[10], stack->grs0[11], stack->grs0[12], stack->grs0[13]); >> + >> + if (sie) { >> + sblk = (struct kvm_s390_sie_block *)stack->grs0[12]; >> + printf("%016lx %016lx %016lx %016lx\n", >> + stack->grs0[10], stack->grs0[11], sblk->gg14, sblk->gg15); >> + } else { >> + printf("%016lx %016lx %016lx %016lx\n", >> + stack->grs0[10], stack->grs0[11], stack->grs0[12], stack->grs0[13]); >> + } >> + >> printf("\n"); >> } >> >> static void print_pgm_info(struct stack_frame_int *stack) >> >> { >> - bool in_sie; >> + bool in_sie, in_sie_gregs; >> + struct vm_save_area *vregs; >> >> in_sie = (lowcore.pgm_old_psw.addr >= (uintptr_t)sie_entry && >> lowcore.pgm_old_psw.addr <= (uintptr_t)sie_exit); >> + in_sie_gregs = (lowcore.pgm_old_psw.addr >= (uintptr_t)sie_entry_gregs && >> + lowcore.pgm_old_psw.addr <= (uintptr_t)sie_exit_gregs); > > can you explain why <= instead of < ? (I think I know why, but a > comment would not hurt) This might be wrong now that the exit label points behind a lmg which can only cause the operation or the addressing exception. The operation exception can only happen on a LMY without the long displacement HW support and the addressing exception should only happen in circumstances where any processed instruction will likely result in a new exception being thrown. > > with that fixed: > > Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com> > >> >> printf("\n"); >> printf("Unexpected program interrupt %s: %#x on cpu %d at %#lx, ilen %d\n", >> in_sie ? "in SIE" : "", >> lowcore.pgm_int_code, stap(), lowcore.pgm_old_psw.addr, lowcore.pgm_int_id); >> - print_int_regs(stack); >> + >> + /* >> + * If we fall out of SIE before loading the host registers, >> + * then we need to do it here so we print the host registers >> + * and not the guest registers. >> + * >> + * Back tracing is actually not a problem since SIE restores gr15. >> + */ >> + if (in_sie_gregs) { >> + print_int_regs(stack, true); >> + vregs = *((struct vm_save_area **)(stack->grs0[13] + __SF_SIE_SAVEAREA)); >> + >> + /* >> + * The grs are not linear on the interrupt stack frame. >> + * We copy 0 and 1 here and 2 - 15 with the memcopy below. >> + */ >> + stack->grs1[0] = vregs->host.grs[0]; >> + stack->grs1[1] = vregs->host.grs[1]; >> + /* 2 - 15 */ >> + memcpy(stack->grs0, &vregs->host.grs[2], sizeof(stack->grs0) - 8); >> + } >> + print_int_regs(stack, false); >> dump_stack(); >> >> /* Dump stack doesn't end with a \n so we add it here instead */ >> diff --git a/lib/s390x/sie.h b/lib/s390x/sie.h >> index a27a8401..147cb0f2 100644 >> --- a/lib/s390x/sie.h >> +++ b/lib/s390x/sie.h >> @@ -273,6 +273,8 @@ struct vm { >> >> extern void sie_entry(void); >> extern void sie_exit(void); >> +extern void sie_entry_gregs(void); >> +extern void sie_exit_gregs(void); >> extern void sie64a(struct kvm_s390_sie_block *sblk, struct vm_save_area *save_area); >> void sie(struct vm *vm); >> void sie_expect_validity(struct vm *vm); >> diff --git a/s390x/cpu.S b/s390x/cpu.S >> index 45bd551a..9155b044 100644 >> --- a/s390x/cpu.S >> +++ b/s390x/cpu.S >> @@ -82,7 +82,8 @@ sie64a: >> # Store scb and save_area pointer into stack frame >> stg %r2,__SF_SIE_CONTROL(%r15) # save control block pointer >> stg %r3,__SF_SIE_SAVEAREA(%r15) # save guest register save area >> - >> +.globl sie_entry_gregs >> +sie_entry_gregs: >> # Load guest's gprs, fprs and fpc >> .irp i, 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15 >> ld \i, \i * 8 + SIE_SAVEAREA_GUEST_FPRS(%r3) >> @@ -121,7 +122,8 @@ sie_exit: >> .endr >> lfpc SIE_SAVEAREA_HOST_FPC(%r14) >> lmg %r0,%r14,SIE_SAVEAREA_HOST_GRS(%r14) # restore kernel registers >> - >> +.globl sie_exit_gregs >> +sie_exit_gregs: >> br %r14 >> >> .align 8 >
diff --git a/lib/s390x/interrupt.c b/lib/s390x/interrupt.c index dadb7415..ff47c2c2 100644 --- a/lib/s390x/interrupt.c +++ b/lib/s390x/interrupt.c @@ -9,6 +9,7 @@ */ #include <libcflat.h> #include <asm/barrier.h> +#include <asm/asm-offsets.h> #include <sclp.h> #include <interrupt.h> #include <sie.h> @@ -188,9 +189,12 @@ static void print_storage_exception_information(void) } } -static void print_int_regs(struct stack_frame_int *stack) +static void print_int_regs(struct stack_frame_int *stack, bool sie) { + struct kvm_s390_sie_block *sblk; + printf("\n"); + printf("%s\n", sie ? "Guest registers:" : "Host registers:"); printf("GPRS:\n"); printf("%016lx %016lx %016lx %016lx\n", stack->grs1[0], stack->grs1[1], stack->grs0[0], stack->grs0[1]); @@ -198,24 +202,56 @@ static void print_int_regs(struct stack_frame_int *stack) stack->grs0[2], stack->grs0[3], stack->grs0[4], stack->grs0[5]); printf("%016lx %016lx %016lx %016lx\n", stack->grs0[6], stack->grs0[7], stack->grs0[8], stack->grs0[9]); - printf("%016lx %016lx %016lx %016lx\n", - stack->grs0[10], stack->grs0[11], stack->grs0[12], stack->grs0[13]); + + if (sie) { + sblk = (struct kvm_s390_sie_block *)stack->grs0[12]; + printf("%016lx %016lx %016lx %016lx\n", + stack->grs0[10], stack->grs0[11], sblk->gg14, sblk->gg15); + } else { + printf("%016lx %016lx %016lx %016lx\n", + stack->grs0[10], stack->grs0[11], stack->grs0[12], stack->grs0[13]); + } + printf("\n"); } static void print_pgm_info(struct stack_frame_int *stack) { - bool in_sie; + bool in_sie, in_sie_gregs; + struct vm_save_area *vregs; in_sie = (lowcore.pgm_old_psw.addr >= (uintptr_t)sie_entry && lowcore.pgm_old_psw.addr <= (uintptr_t)sie_exit); + in_sie_gregs = (lowcore.pgm_old_psw.addr >= (uintptr_t)sie_entry_gregs && + lowcore.pgm_old_psw.addr <= (uintptr_t)sie_exit_gregs); printf("\n"); printf("Unexpected program interrupt %s: %#x on cpu %d at %#lx, ilen %d\n", in_sie ? "in SIE" : "", lowcore.pgm_int_code, stap(), lowcore.pgm_old_psw.addr, lowcore.pgm_int_id); - print_int_regs(stack); + + /* + * If we fall out of SIE before loading the host registers, + * then we need to do it here so we print the host registers + * and not the guest registers. + * + * Back tracing is actually not a problem since SIE restores gr15. + */ + if (in_sie_gregs) { + print_int_regs(stack, true); + vregs = *((struct vm_save_area **)(stack->grs0[13] + __SF_SIE_SAVEAREA)); + + /* + * The grs are not linear on the interrupt stack frame. + * We copy 0 and 1 here and 2 - 15 with the memcopy below. + */ + stack->grs1[0] = vregs->host.grs[0]; + stack->grs1[1] = vregs->host.grs[1]; + /* 2 - 15 */ + memcpy(stack->grs0, &vregs->host.grs[2], sizeof(stack->grs0) - 8); + } + print_int_regs(stack, false); dump_stack(); /* Dump stack doesn't end with a \n so we add it here instead */ diff --git a/lib/s390x/sie.h b/lib/s390x/sie.h index a27a8401..147cb0f2 100644 --- a/lib/s390x/sie.h +++ b/lib/s390x/sie.h @@ -273,6 +273,8 @@ struct vm { extern void sie_entry(void); extern void sie_exit(void); +extern void sie_entry_gregs(void); +extern void sie_exit_gregs(void); extern void sie64a(struct kvm_s390_sie_block *sblk, struct vm_save_area *save_area); void sie(struct vm *vm); void sie_expect_validity(struct vm *vm); diff --git a/s390x/cpu.S b/s390x/cpu.S index 45bd551a..9155b044 100644 --- a/s390x/cpu.S +++ b/s390x/cpu.S @@ -82,7 +82,8 @@ sie64a: # Store scb and save_area pointer into stack frame stg %r2,__SF_SIE_CONTROL(%r15) # save control block pointer stg %r3,__SF_SIE_SAVEAREA(%r15) # save guest register save area - +.globl sie_entry_gregs +sie_entry_gregs: # Load guest's gprs, fprs and fpc .irp i, 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15 ld \i, \i * 8 + SIE_SAVEAREA_GUEST_FPRS(%r3) @@ -121,7 +122,8 @@ sie_exit: .endr lfpc SIE_SAVEAREA_HOST_FPC(%r14) lmg %r0,%r14,SIE_SAVEAREA_HOST_GRS(%r14) # restore kernel registers - +.globl sie_exit_gregs +sie_exit_gregs: br %r14 .align 8
When we leave SIE due to an exception, we'll still have guest values in registers 0 - 13 and that's not clearly portraied in our debug prints. So let's fix that. Signed-off-by: Janosch Frank <frankja@linux.ibm.com> --- lib/s390x/interrupt.c | 46 ++++++++++++++++++++++++++++++++++++++----- lib/s390x/sie.h | 2 ++ s390x/cpu.S | 6 ++++-- 3 files changed, 47 insertions(+), 7 deletions(-)