[Crash-utility] 答复: [External Mail]Re: [PATCH v4] 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.

Before: crash> mod -s zram zram.ko MODULE NAME BASE SIZE OBJECT FILE ffffffde224db800 zram ffffffde224d2000 57344 zram.ko crash> mod -s zsmalloc zsmalloc.ko MODULE NAME BASE SIZE OBJECT FILE ffffffde224c5180 zsmalloc ffffffde224bf000 40960 zsmalloc.ko crash> rd 0x13d89fb0 rd: zspage magic incorrect: b0 After: crash> rd 0x13d89fb0 13d89fb0: c2b54f7170883b20 ;.pqO.. Link: https://lkml.kernel.org/r/20211115185909.3949505-6-minchan@kernel.org

Signed-off-by: chenguanyou <chenguanyou(a)xiaomi.com&gt; --- defs.h | 13 +++++++++++ diskdump.c | 67 ++++++++++++++++++++++++++++++++++++++++++++---------- 2 files changed, 68 insertions(+), 12 deletions(-) diff --git a/defs.h b/defs.h index 96a7a2a..0af69cc 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 */ @@ -7221,6 +7222,18 @@ struct zspage { unsigned int freeobj; }; +struct zspage6 {

+ struct { + unsigned int huge : 1; + unsigned int fullness : 2; + unsigned int class : 9; + unsigned int isolated : 3; + unsigned int magic : 8; + }; + unsigned int inuse; + unsigned int freeobj; +}; + /* * makedumpfile.c */ diff --git a/diskdump.c b/diskdump.c index 2c284ff..02aaf1b 100644 --- a/diskdump.c +++ b/diskdump.c @@ -2754,6 +2754,9 @@ zram_init(void) if (INVALID_MEMBER(zram_table_flag)) MEMBER_OFFSET_INIT(zram_table_flag, "zram_table_entry", "value"); STRUCT_SIZE_INIT(zram_table_entry, "zram_table_entry"); + MEMBER_OFFSET_INIT(zspoll_size_class, "zs_pool", "size_class"); + MEMBER_OFFSET_INIT(size_class_size, "size_class", "size"); + MEMBER_OFFSET_INIT(zspage_huge, "zspage", "huge"); } static unsigned char * @@ -2761,9 +2764,11 @@ zram_object_addr(ulong pool, ulong handle, unsigned char *zram_buf) { ulong obj, off, class, page, zspage; struct zspage zspage_s; + struct zspage6 zspage6_s; physaddr_t paddr; unsigned int obj_idx, class_idx, size; ulong pages[2], sizes[2]; + ulong zs_magic; readmem(handle, KVADDR, &obj, sizeof(void *), "zram entry", FAULT_ON_ERROR); obj >>= OBJ_TAG_BITS; @@ -2772,11 +2777,19 @@ zram_object_addr(ulong pool, ulong handle, unsigned char *zram_buf) readmem(page + OFFSET(page_private), KVADDR, &zspage, 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)) { + readmem(zspage, KVADDR, &zspage6_s, sizeof(struct zspage6), "zspage6", FAULT_ON_ERROR); + class_idx = zspage6_s.class; + zs_magic = zspage6_s.magic; + } else { + readmem(zspage, KVADDR, &zspage_s, sizeof(struct zspage), "zspage", FAULT_ON_ERROR); + class_idx = zspage_s.class; + zs_magic = zspage_s.magic; + } + + 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 +2807,13 @@ 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)) { @@ -2812,9 +2830,15 @@ zram_object_addr(ulong pool, ulong handle, unsigned char *zram_buf) readmem(paddr, PHYSADDR, zram_buf + sizes[0], sizes[1], "zram buffer[1]", FAULT_ON_ERROR); out: - readmem(page, KVADDR, &obj, sizeof(void *), "page flags", FAULT_ON_ERROR); - if (!(obj & (1<<10))) { //PG_OwnerPriv1 flag - return (zram_buf + ZS_HANDLE_SIZE); + if (!VALID_MEMBER(zspage_huge)) { + readmem(page, KVADDR, &obj, sizeof(void *), "page flags", FAULT_ON_ERROR); + if (!(obj & (1<<10))) { //PG_OwnerPriv1 flag + return (zram_buf + ZS_HANDLE_SIZE); + } + } else { + if (!zspage6_s.huge) { + return (zram_buf + ZS_HANDLE_SIZE); + } } return zram_buf; @@ -2929,6 +2953,11 @@ try_zram_decompress(ulonglong pte_val, unsigned char *buf, ulong len, ulonglong unsigned char *outbuf = NULL; ulong zram, zram_table_entry, sector, index, entry, flags, size, outsize, off; + unsigned long *same_buf = NULL; + bool is_same = false; + ulong ZRAM_SAME_PAGEFLAG; + ulong ZRAM_WB_PAGEFLAG; + long ZRAM_LOCK_VALUE = 24; if (INVALID_MEMBER(zram_compressor)) { zram_init(); @@ -2992,11 +3021,25 @@ try_zram_decompress(ulonglong pte_val, unsigned char *buf, ulong len, ulonglong sizeof(void *), "entry of table", FAULT_ON_ERROR); readmem(zram_table_entry + OFFSET(zram_table_flag), KVADDR, &flags, sizeof(void *), "zram_table_flag", FAULT_ON_ERROR); - if (!entry || (flags & ZRAM_FLAG_SAME_BIT)) { - memset(buf, entry, len); + + if (!enumerator_value("ZRAM_LOCK", &ZRAM_LOCK_VALUE) + && THIS_KERNEL_VERSION >= LINUX(6,1,0)) + ZRAM_LOCK_VALUE = PAGESHIFT() + 1; + + ZRAM_SAME_PAGEFLAG = ZRAM_LOCK_VALUE + 1; + ZRAM_WB_PAGEFLAG = ZRAM_LOCK_VALUE + 2; + + if (!entry || flags & (1 << ZRAM_SAME_PAGEFLAG)) { + same_buf = (unsigned long *)GETBUF(PAGESIZE()); + for (int count = 0; count < PAGESIZE() / sizeof(unsigned long); count++) { + same_buf[count] = entry; + } + memcpy(buf, same_buf + off, PAGESIZE()); + FREEBUF(same_buf);

goto out; } - size = flags & (ZRAM_FLAG_SHIFT -1); + + size = flags & ((1 << ZRAM_LOCK_VALUE) - 1); if (size == 0) { len = 0; goto out; -- 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!******/#