Re: [Crash-utility] [PATCH] Fix for "kmem -n" option on Linux 5.4-rc1

From: Masayoshi Mizuma <m.mizuma(a)jp.fujitsu.com&gt; Fix for Linux 5.4-rc1 and later kernels that contain commit b6c88d3b9d38 ("drivers/base/memory.c: don't store end_section_nr in memory blocks"). Without this patch, kmem -n stops as the following: crash> kmem -n ... kmem: invalid structure member offset: memory_block_end_section_nr FILE: memory.c LINE: 17426 FUNCTION: print_memory_block() [./crash] error trace: 4b0b83 => 4b00fe => 5430e1 => 543063 543063: OFFSET_verify.part.28+51 5430e1: OFFSET_verify+49 4b00fe: print_memory_block+147 4b0b83: dump_memory_blocks+813 To fix this, use either memory_block_size_probed. If the symbol doesn't exist, then use memory_block.end_section_nr. Either value should be available on the kernel. And the start section number is enough to get the memory block, so change the output to show the start section number. Signed-off-by: Masayoshi Mizuma <m.mizuma(a)jp.fujitsu.com&gt; --- help.c | 2 +- memory.c | 42 +++++++++++++++++++++++++----------------- 2 files changed, 26 insertions(+), 18 deletions(-) diff --git a/help.c b/help.c index a5218a7..cfd46c3 100644 --- a/help.c +++ b/help.c @@ -7177,7 +7177,7 @@ char *help_kmem[] = { " 6 ffff88003d4d90c0 ffffea0000000000 ffffea0000c00000 PM 196608", " 7 ffff88003d4d90e0 ffffea0000000000 ffffea0000e00000 PM 229376", " ", -" MEM_BLOCK NAME PHYSICAL RANGE STATE SECTIONS", +" MEM_BLOCK NAME PHYSICAL RANGE STATE START_SECTION_NO", " ffff88003a707c00 memory0 0 - 7ffffff ONLINE 0", " ffff88003a6e0000 memory1 8000000 - fffffff ONLINE 1", " ffff88003a6e1000 memory2 10000000 - 17ffffff ONLINE 2", diff --git a/memory.c b/memory.c index fe82fac..a7ed915 100644 --- a/memory.c +++ b/memory.c @@ -17402,20 +17402,18 @@ fill_memory_block_name(ulong memblock, char *name) } static void -fill_memory_block_srange(ulong start_sec, ulong end_sec, char *srange) +fill_memory_block_srange(ulong start_sec, char *srange) { memset(srange, 0, sizeof(*srange) * BUFSIZE); - if (start_sec == end_sec) - sprintf(srange, "%lu", start_sec); - else - sprintf(srange, "%lu-%lu", start_sec, end_sec); + sprintf(srange, "%lu", start_sec); } static void print_memory_block(ulong memory_block) { ulong start_sec, end_sec, start_pfn, end_pfn, nid; + ulong memblock_size, mbs, start_addr, end_addr; char statebuf[BUFSIZE]; char srangebuf[BUFSIZE]; char name[BUFSIZE]; @@ -17430,15 +17428,25 @@ print_memory_block(ulong memory_block) readmem(memory_block + OFFSET(memory_block_start_section_nr), KVADDR, &start_sec, sizeof(void *), "memory_block start_section_nr", FAULT_ON_ERROR); - readmem(memory_block + OFFSET(memory_block_end_section_nr), KVADDR, - &end_sec, sizeof(void *), "memory_block end_section_nr", - FAULT_ON_ERROR); - start_pfn = section_nr_to_pfn(start_sec); - end_pfn = section_nr_to_pfn(end_sec + 1); + start_addr = pfn_to_phys(section_nr_to_pfn(start_sec)); + + if (symbol_exists("memory_block_size_probed")) { + memblock_size = symbol_value("memory_block_size_probed"); + readmem(memblock_size, KVADDR, + &mbs, sizeof(ulong), "memory_block_size_probed", + FAULT_ON_ERROR); + end_addr = start_addr + mbs - 1; + } else { + readmem(memory_block + OFFSET(memory_block_end_section_nr), KVADDR, + &end_sec, sizeof(void *), "memory_block end_section_nr", + FAULT_ON_ERROR); + end_addr = pfn_to_phys(section_nr_to_pfn(end_sec + 1)) - 1; + } + fill_memory_block_state(memory_block, statebuf); fill_memory_block_name(memory_block, name); - fill_memory_block_srange(start_sec, end_sec, srangebuf); + fill_memory_block_srange(start_sec, srangebuf); if (MEMBER_EXISTS("memory_block", "nid")) { readmem(memory_block + OFFSET(memory_block_nid), KVADDR, &nid, @@ -17448,9 +17456,9 @@ print_memory_block(ulong memory_block) MKSTR(memory_block)), mkstring(buf2, 12, CENTER, name), mkstring(buf3, PADDR_PRLEN, RJUST|LONG_HEX, - MKSTR(pfn_to_phys(start_pfn))), + MKSTR(start_addr)), mkstring(buf4, PADDR_PRLEN, LJUST|LONG_HEX, - MKSTR(pfn_to_phys(end_pfn) - 1)), + MKSTR(end_addr)), mkstring(buf5, strlen("NODE"), CENTER|LONG_DEC, MKSTR(nid)), mkstring(buf6, strlen("CANCEL_OFFLINE"), LJUST, @@ -17462,9 +17470,9 @@ print_memory_block(ulong memory_block) MKSTR(memory_block)), mkstring(buf2, 10, CENTER, name), mkstring(buf3, PADDR_PRLEN, RJUST|LONG_HEX, - MKSTR(pfn_to_phys(start_pfn))), + MKSTR(start_addr)), mkstring(buf4, PADDR_PRLEN, LJUST|LONG_HEX, - MKSTR(pfn_to_phys(end_pfn) - 1)), + MKSTR(end_addr)), mkstring(buf5, strlen("CANCEL_OFFLINE"), LJUST, statebuf), mkstring(buf6, 12, LJUST, srangebuf)); @@ -17552,14 +17560,14 @@ dump_memory_blocks(int initialize) mkstring(buf3, PADDR_PRLEN*2 + 2, CENTER, "PHYSICAL RANGE"), mkstring(buf4, strlen("NODE"), CENTER, "NODE"), mkstring(buf5, strlen("CANCEL_OFFLINE"), LJUST, "STATE"), - mkstring(buf6, 12, LJUST, "SECTIONS")); + mkstring(buf6, 12, LJUST, "START_SECTION_NO")); else sprintf(mb_hdr, "\n%s %s %s %s %s\n", mkstring(buf1, VADDR_PRLEN, CENTER|LJUST, "MEM_BLOCK"), mkstring(buf2, 10, CENTER, "NAME"), mkstring(buf3, PADDR_PRLEN*2, CENTER, "PHYSICAL RANGE"), mkstring(buf4, strlen("CANCEL_OFFLINE"), LJUST, "STATE"), - mkstring(buf5, 12, LJUST, "SECTIONS")); + mkstring(buf5, 12, LJUST, "START_SECTION_NO")); fprintf(fp, "%s", mb_hdr); for (i = 0; i < klistcnt; i++) { -- 2.18.1 -- Crash-utility mailing list Crash-utility(a)redhat.com https://www.redhat.com/mailman/listinfo/crash-utility