[Crash-utility] [PATCH] Fix: move huge compressed obj from page to zspage

when zspage define 'huge', crash-utility zram decompress fail. we need to be compatible with the previous kernel, so we can't define 'huge' directly in zspage, just move to the right when calculating. Link: https://lkml.kernel.org/r/20211115185909.3949505-6-minchan@kernel.org Signed-off-by: chenguanyou <chenguanyou(a)xiaomi.com&gt; --- defs.h | 4 ++++ diskdump.c | 21 ++++++++++++++++----- 2 files changed, 20 insertions(+), 5 deletions(-) diff --git a/defs.h b/defs.h index 96a7a2a..ac19410 100644 --- a/defs.h +++ b/defs.h @@ -2225,6 +2225,7 @@ struct offset_table { /* stash of commonly-used offsets */ long module_memory_base; long module_memory_size; long irq_data_irq; + long zspage_huge; }; struct size_table { /* stash of commonly-used sizes */ @@ -7212,6 +7213,9 @@ ulong try_zram_decompress(ulonglong pte_val, unsigned char *buf, ulong len, ulon #define ZRAM_FLAG_SAME_BIT (1<<25) struct zspage { struct { + // Link: https://lkml.kernel.org/r/20211115185909.3949505-6-minchan@kernel.org + // unsigned int huge : 1; // compatible + unsigned int fullness : 2; unsigned int class : 9; unsigned int isolated : 3; diff --git a/diskdump.c b/diskdump.c index 2c284ff..891ee2f 100644 --- a/diskdump.c +++ b/diskdump.c @@ -2764,6 +2764,8 @@ zram_object_addr(ulong pool, ulong handle, unsigned char *zram_buf) physaddr_t paddr; unsigned int obj_idx, class_idx, size; ulong pages[2], sizes[2]; + ulong zspage_shift = 0; + ulong zs_magic; readmem(handle, KVADDR, &obj, sizeof(void *), "zram entry", FAULT_ON_ERROR); obj >>= OBJ_TAG_BITS; @@ -2774,9 +2776,13 @@ zram_object_addr(ulong pool, ulong handle, unsigned char *zram_buf) sizeof(void *), "page_private", FAULT_ON_ERROR); readmem(zspage, KVADDR, &zspage_s, sizeof(struct zspage), "zspage", FAULT_ON_ERROR); - class_idx = zspage_s.class; - if (zspage_s.magic != ZSPAGE_MAGIC) - error(FATAL, "zspage magic incorrect: %x\n", zspage_s.magic); + if (VALID_MEMBER(zspage_huge)) + zspage_shift = 1; // huge shift + + class_idx = zspage_s.class >> zspage_shift; + zs_magic = zspage_s.magic >> zspage_shift; + if (zs_magic != ZSPAGE_MAGIC) + error(FATAL, "zspage magic incorrect: %x\n", zs_magic); class = pool + OFFSET(zspoll_size_class); class += (class_idx * sizeof(void *)); @@ -2794,8 +2800,13 @@ zram_object_addr(ulong pool, ulong handle, unsigned char *zram_buf) } pages[0] = page; - readmem(page + OFFSET(page_freelist), KVADDR, &pages[1], - sizeof(void *), "page_freelist", FAULT_ON_ERROR); + if (VALID_MEMBER(page_freelist)) { + readmem(page + OFFSET(page_freelist), KVADDR, &pages[1], + sizeof(void *), "page_freelist", FAULT_ON_ERROR); + } else { + readmem(page + OFFSET(page_index), KVADDR, &pages[1], + sizeof(void *), "page_index", FAULT_ON_ERROR); + } sizes[0] = PAGESIZE() - off; sizes[1] = size - sizes[0]; if (!is_page_ptr(pages[0], &paddr)) { -- 2.39.0 #/******本邮件及其附件含有小米公司的保密信息，仅限于发送给上面地址中列出的个人或群组。禁止任何其他人以任何形式使用（包括但不限于全部或部分地泄露、复制、或散发）本邮件中的信息。如果您错收了本邮件，请您立即电话或邮件通知发件人并删除本邮件！ This e-mail and its attachments contain confidential information from XIAOMI, which is intended only for the person or entity whose address is listed above. Any use of the information contained herein in any way (including, but not limited to, total or partial disclosure, reproduction, or dissemination) by persons other than the intended recipient(s) is prohibited. If you receive this e-mail in error, please notify the sender by phone or email immediately and delete it!******/#