arm64/pgtable: support __HAVE_ARCH_PTE_SWP_EXCLUSIVE Let's use one of the type bits: core-mm only supports 5, so there is no need to consume 6. Note that we might be able to reuse bit 1, but reusing bit 1 turned out problematic in the past for PROT_NONE handling; so let's play safe and use another bit. Link: https://lkml.kernel.org/r/20220329164329.208407-5-david@redhat.com Before: crash> vtop 70504000 VIRTUAL PHYSICAL 70504000 (not mapped) PAGE DIRECTORY: ffffff80f265c000 PGD: ffffff80f265c008 => 800000141537003 PMD: ffffff8101537c10 => 800000141538003 PTE: ffffff8101538820 => 12bc3e04 PTE vtop: cannot determine swap location After: crash> vtop 70504000 VIRTUAL PHYSICAL 70504000 (not mapped) PAGE DIRECTORY: ffffff80f265c000 PGD: ffffff80f265c008 => 800000141537003 PMD: ffffff8101537c10 => 800000141538003 PTE: ffffff8101538820 => 12bc3e04 PTE SWAP OFFSET 12bc3e04 /first_stage_ramdisk/dev/block/zram0 1227838 VMA START END FLAGS FILE ffffff80dfe7b578 70504000 707bd000 100073 SWAP: /first_stage_ramdisk/dev/block/zram0 OFFSET: 1227838 Signed-off-by: chenguanyou <chenguanyou(a)xiaomi.com&gt; --- arm64.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/arm64.c b/arm64.c index 39d5f04..ea1b51b 100644 --- a/arm64.c +++ b/arm64.c @@ -468,8 +468,16 @@ arm64_init(int when) } } - - if (THIS_KERNEL_VERSION >= LINUX(4,0,0)) { + if (THIS_KERNEL_VERSION >= LINUX(5,19,0)) { + ms->__SWP_TYPE_BITS = 5; + ms->__SWP_TYPE_SHIFT = 3; + ms->__SWP_TYPE_MASK = ((1UL << ms->__SWP_TYPE_BITS) - 1); + ms->__SWP_OFFSET_SHIFT = (ms->__SWP_TYPE_BITS + ms->__SWP_TYPE_SHIFT); + ms->__SWP_OFFSET_BITS = 50; + ms->__SWP_OFFSET_MASK = ((1UL << ms->__SWP_OFFSET_BITS) - 1); + ms->PTE_PROT_NONE = (1UL << 58); + ms->PTE_FILE = 0; /* unused */ + } else if (THIS_KERNEL_VERSION >= LINUX(4,0,0)) { ms->__SWP_TYPE_BITS = 6; ms->__SWP_TYPE_SHIFT = 2; ms->__SWP_TYPE_MASK = ((1UL << ms->__SWP_TYPE_BITS) - 1); -- 2.39.0 -- Crash-utility mailing list Crash-utility(a)redhat.com https://listman.redhat.com/mailman/listinfo/crash-utility Contribution Guidelines: https://github.com/crash-utility/crash/wiki

Thank you for the update, Chen. On Tue, Sep 26, 2023 at 8:44 PM Guanyou Chen <chenguanyou9338(a)gmail.com&gt; wrote: > arm64/pgtable: support __HAVE_ARCH_PTE_SWP_EXCLUSIVE > > We can add the kernel commit to patch log as I mentioned here: https://listman.redhat.com/archives/crash-utility/2023-September/011010.html 570ef363509b ("arm64/pgtable: support __HAVE_ARCH_PTE_SWP_EXCLUSIVE") Otherwise, for the patch: Ack. BTW: maybe Kazu can help improve the patch log when merging(if the patch is also fine to him). Thanks Lianbo Let's use one of the type bits: core-mm only supports 5, so there is no > need to consume 6. > > Note that we might be able to reuse bit 1, but reusing bit 1 turned out > problematic in the past for PROT_NONE handling; so let's play safe and use > another bit. > > Link: https://lkml.kernel.org/r/20220329164329.208407-5-david@redhat.com > > Before: > crash> vtop 70504000 > VIRTUAL PHYSICAL > 70504000 (not mapped) > > PAGE DIRECTORY: ffffff80f265c000 > PGD: ffffff80f265c008 => 800000141537003 > PMD: ffffff8101537c10 => 800000141538003 > PTE: ffffff8101538820 => 12bc3e04 > > PTE vtop: cannot determine swap location > > After: > crash> vtop 70504000 > VIRTUAL PHYSICAL > 70504000 (not mapped) > > PAGE DIRECTORY: ffffff80f265c000 > PGD: ffffff80f265c008 => 800000141537003 > PMD: ffffff8101537c10 => 800000141538003 > PTE: ffffff8101538820 => 12bc3e04 > > PTE SWAP OFFSET > 12bc3e04 /first_stage_ramdisk/dev/block/zram0 1227838 > > VMA START END FLAGS FILE > ffffff80dfe7b578 70504000 707bd000 100073 > > SWAP: /first_stage_ramdisk/dev/block/zram0 OFFSET: 1227838 > > Signed-off-by: chenguanyou <chenguanyou(a)xiaomi.com&gt; > --- > arm64.c | 12 ++++++++++-- > 1 file changed, 10 insertions(+), 2 deletions(-) > > diff --git a/arm64.c b/arm64.c > index 39d5f04..ea1b51b 100644 > --- a/arm64.c > +++ b/arm64.c > @@ -468,8 +468,16 @@ arm64_init(int when) > } > } > > - > - if (THIS_KERNEL_VERSION >= LINUX(4,0,0)) { > + if (THIS_KERNEL_VERSION >= LINUX(5,19,0)) { > + ms->__SWP_TYPE_BITS = 5; > + ms->__SWP_TYPE_SHIFT = 3; > + ms->__SWP_TYPE_MASK = ((1UL << ms->__SWP_TYPE_BITS) - 1); > + ms->__SWP_OFFSET_SHIFT = (ms->__SWP_TYPE_BITS + > ms->__SWP_TYPE_SHIFT); > + ms->__SWP_OFFSET_BITS = 50; > + ms->__SWP_OFFSET_MASK = ((1UL << ms->__SWP_OFFSET_BITS) - 1); > + ms->PTE_PROT_NONE = (1UL << 58); > + ms->PTE_FILE = 0; /* unused */ > + } else if (THIS_KERNEL_VERSION >= LINUX(4,0,0)) { > ms->__SWP_TYPE_BITS = 6; > ms->__SWP_TYPE_SHIFT = 2; > ms->__SWP_TYPE_MASK = ((1UL << ms->__SWP_TYPE_BITS) - 1); > -- > 2.39.0 >