-----Original Message----- > > At present, we have the following important changes for arm64 memory > layout: > > -1. redesigned ARM64 kernel virtual memory layout and associated KASLR > support that was introduced in Linux 4.6. And NEW_VMEMMAP is used to > flag it. > -2. memory layout flipped just right before introducing 52-bits kernel. > -3. introducing of vabits_actual and phyvirt_offset in kernel > -4. removing phyvirt_offset. > > These changes have effects on PTOV()/VTOP() formula. So introducing a > dedicate field mmlayout_flags to record it.
arm64 already has machine_specific.flags, can't we use this? Also, to record the type of memory layout is good, please display it with "help -m". And I'd prefer shorter names like HAS_PHYSVIRT_OFFSET and FLIPPED_VM for them, as they will be shown in "help -m". Thanks, Kazu > > Among above, 2 and 3 are introduced closely, and are not distinguished > in current implement. And this patch also keep this practice and use > vabits_actual as a hint to flag mem flipped. > > Signed-off-by: Pingfan Liu <[email protected]> > Cc: HAGIO KAZUHITO <[email protected]> > Cc: Lianbo Jiang <[email protected]> > Cc: Bhupesh Sharma <[email protected]> > To: [email protected] > --- > arm64.c | 11 +++++++++++ > defs.h | 1 + > 2 files changed, 12 insertions(+) > > diff --git a/arm64.c b/arm64.c > index 8934961..eb88ced 100644 > --- a/arm64.c > +++ b/arm64.c > @@ -88,6 +88,10 @@ static int arm64_is_uvaddr(ulong, struct task_context *); > static void arm64_calc_KERNELPACMASK(void); > > > +/* arm64 kernel layout experiences changes, using these flags to distinguish > them */ > +#define MMLAYOUT_FLAGS_FLIP 0x1 > +#define MMLAYOUT_FLAGS_HAS_PHYSVIRT_OFFSET 0x2 > + > /* > * Do all necessary machine-specific setup here. This is called several times > * during initialization. > @@ -994,6 +998,7 @@ arm64_calc_physvirt_offset(void) > if (READMEM(pc->mfd, &physvirt_offset, sizeof(physvirt_offset), > sp->value, sp->value - > machdep->machspec->kimage_voffset) > 0) { > + machdep->machspec->mmlayout_flags |= > MMLAYOUT_FLAGS_HAS_PHYSVIRT_OFFSET; > ms->physvirt_offset = physvirt_offset; > } > } > @@ -3923,6 +3928,7 @@ arm64_calc_VA_BITS(void) > if (kernel_symbol_exists("vabits_actual")) { > if (pc->flags & PROC_KCORE) { > vabits_actual = > symbol_value_from_proc_kallsyms("vabits_actual"); > + machdep->machspec->mmlayout_flags |= > MMLAYOUT_FLAGS_FLIP; > if ((vabits_actual != BADVAL) && (READMEM(pc->mfd, > &value, sizeof(ulong), > vabits_actual, KCORE_USE_VADDR) > 0)) { > if (CRASHDEBUG(1)) > @@ -3953,6 +3959,11 @@ arm64_calc_VA_BITS(void) > machdep->machspec->VA_BITS_ACTUAL = value; > machdep->machspec->VA_BITS = value; > machdep->machspec->VA_START = > _VA_START(machdep->machspec->VA_BITS_ACTUAL); > + /* > + * The mm flip commit is introduced before > 52-bits VA, which is before the > + * commit to export NUMBER(TCR_EL1_T1SZ) > + */ > + machdep->machspec->mmlayout_flags |= > MMLAYOUT_FLAGS_FLIP; > } else if (machdep->machspec->VA_BITS_ACTUAL) { > machdep->machspec->VA_BITS = > machdep->machspec->VA_BITS_ACTUAL; > machdep->machspec->VA_START = > _VA_START(machdep->machspec->VA_BITS_ACTUAL); > diff --git a/defs.h b/defs.h > index 396d61a..22b3cbd 100644 > --- a/defs.h > +++ b/defs.h > @@ -3290,6 +3290,7 @@ struct arm64_pt_regs { > struct machine_specific { > ulong flags; > ulong userspace_top; > + ulong mmlayout_flags; > ulong page_offset; > ulong vmalloc_start_addr; > ulong vmalloc_end; > -- > 2.29.2 -- Crash-utility mailing list [email protected] https://listman.redhat.com/mailman/listinfo/crash-utility
