[Crash-utility] [PATCH] arm64: Fix "vtop" command to display swap information on Linux 6.10 and later

Hi Lianbo Kernel commit 55564814a838 ("arm64/mm: Move PTE_PRESENT_INVALID to overlay PTE_NG"), which is contained in Linux 6.10 and later kernels, changed the format of swap entries on arm64. Without the patch, the "vtop" command cannot display swap information before: crash> vtop 2000000 VIRTUAL PHYSICAL 2000000 (not mapped) PAGE DIRECTORY: ffffff8106356000 PGD: ffffff8106356000 => 800000186355003 PMD: ffffff8106355080 => 8000001476f5003 PTE: ffffff80c76f5000 => 101a62004 PTE OFFSET: 1055330 vtop: cannot determine swap location without the patch: crash> vtop 2000000 VIRTUAL PHYSICAL 2000000 (not mapped) PAGE DIRECTORY: ffffff8106356000 PGD: ffffff8106356000 => 800000186355003 PMD: ffffff8106355080 => 8000001476f5003 PTE: ffffff80c76f5000 => 101a62004 PTE SWAP OFFSET 101a62004 /first_stage_ramdisk/dev/block/zram0 1055330 VMA START END FLAGS FILE ffffff81a06e8b00 2000000 22000000 100073 SWAP: /first_stage_ramdisk/dev/block/zram0 OFFSET: 1055330 Link: https://lore.kernel.org/r/20240503144604.151095-4-ryan.roberts@arm.com Signed-off-by: Guanyou.Chen <chenguanyou(a)xiaomi.com&gt; --- arm64.c | 11 ++++++++++- memory.c | 5 ++++- 2 files changed, 14 insertions(+), 2 deletions(-) diff --git a/arm64.c b/arm64.c index 1723595..c125655 100644 --- a/arm64.c +++ b/arm64.c @@ -712,7 +712,16 @@ arm64_init(int when) } } - if (THIS_KERNEL_VERSION >= LINUX(5,19,0)) { + if (THIS_KERNEL_VERSION >= LINUX(6,10,0)) { + ms->__SWP_TYPE_BITS = 5; + ms->__SWP_TYPE_SHIFT = 6; + ms->__SWP_TYPE_MASK = ((1UL << ms->__SWP_TYPE_BITS) - 1); + ms->__SWP_OFFSET_SHIFT = 12; + ms->__SWP_OFFSET_BITS = 50; + ms->__SWP_OFFSET_MASK = ((1UL << ms->__SWP_OFFSET_BITS) - 1); + ms->PTE_PROT_NONE = 0; /* unused */ + ms->PTE_FILE = 0; /* unused */ + } else 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); diff --git a/memory.c b/memory.c index 400d31a..cbc8d2f 100644 --- a/memory.c +++ b/memory.c @@ -16415,6 +16415,8 @@ get_swapdev(ulong type, char *buf) ulong vfsmnt; char *devname; char buf1[BUFSIZE]; + int swap_file_is_file = + STREQ(MEMBER_TYPE_NAME("swap_info_struct", "swap_file"), "file"); swap_info_init(); @@ -16474,7 +16476,8 @@ get_swapdev(ulong type, char *buf) vfsmnt = ULONG(vt->swap_info_struct + OFFSET(swap_info_struct_swap_vfsmnt)); get_pathname(swap_file, buf, BUFSIZE, 1, vfsmnt); - } else if (VALID_MEMBER (swap_info_struct_old_block_size)) { + } else if (VALID_MEMBER (swap_info_struct_old_block_size) + || swap_file_is_file) { devname = vfsmount_devname(file_to_vfsmnt(swap_file), buf1, BUFSIZE); get_pathname(file_to_dentry(swap_file), -- 2.34.1 Thanks. Guanyou