On 08/02/2018 04:45 AM, Kazuhito Hagio wrote: > Hi Pingfan, > > Thank you for the patch. > > On 7/31/2018 4:44 AM, Pingfan Liu wrote: >> When refiltering on kdump format file, there is no info about pt_load[] for >> exclude_nodata_pages(), and also we can not expect more data than the kdump >> file can provide, hence this patch suggests to initialize the refiltered >> bitmap1 from the kdump file's bitmap2. > > I understood the issue (I don't have any vmcore which can reproduce it, > though), but since the bitmap1 is written to the refiltered dump file, > I think that we should not change the meaning of bitmap1 if possible, > which is "a page on memory hole". > > For instance, with the patch, crash using the bitmaps prints a different > message for the same "excluded" paddr: > > -read_diskdump: PAGE_EXCLUDED: paddr/pfn: 2613e130/2613e > +read_diskdump: SEEK_ERROR: paddr/pfn: 2613e130/2613e !page_is_ram > > and makedumpfile's -e option using the bitmap1 cannot be utilized when > refiltering, these are not favorable. > > So how about initializing the refiltered *bitmap2* from the kdump file's > bitmap2 ? I'm checking if this works. > Yes, it sounds a good idea. Thanks, Pingfan > Thanks, > Kazu > >> >> Note about the bug reported by the following ops: >> makedumpfile -l --message-level 1 -d 31 /proc/vmcore /path/to/vmcore >> makedumpfile --split -d 31 ./vmcore dumpfile_{1,2,3} 2>&1 >> and hit the following error: >> Excluding unnecessary pages : [100.0 %] \ >> readpage_kdump_compressed: pfn(9b) is excluded from /var/crash/127.0.0.1-2018-07-02-22:10:38/vmcore. >> readmem: type_addr: 1, addr:9b000, size:4096 >> read_pfn: Can't get the page data. >> writeout_multiple_dumpfiles: Child process(2277) finished incompletely.(256) >> Copying data : [ 24.6 %] - eta: 2s >> makedumpfile Failed. >> >> Signed-off-by: Pingfan Liu <piliu@xxxxxxxxxx> >> --- >> makedumpfile.c | 6 +++++- >> 1 file changed, 5 insertions(+), 1 deletion(-) >> >> diff --git a/makedumpfile.c b/makedumpfile.c >> index 101fa7c..af24359 100644 >> --- a/makedumpfile.c >> +++ b/makedumpfile.c >> @@ -5544,6 +5544,7 @@ copy_1st_bitmap_from_memory(void) >> >> bitmap_offset = (DISKDUMP_HEADER_BLOCKS + dh->sub_hdr_size) >> * dh->block_size; >> + bitmap_offset += info->len_bitmap / 2; >> >> if (lseek(info->fd_memory, bitmap_offset, SEEK_SET) < 0) { >> ERRMSG("Can't seek %s. %s\n", >> @@ -5593,8 +5594,11 @@ create_1st_bitmap_file(void) >> struct timespec ts_start; >> off_t offset_page; >> >> - if (info->flag_refiltering) >> + if (info->flag_refiltering) { >> + /* no hole info in kdump file, set it as 0 for refiltering */ >> + pfn_memhole = 0; >> return copy_1st_bitmap_from_memory(); >> + } >> >> if (info->flag_sadump) >> return sadump_copy_1st_bitmap_from_memory(); >> -- >> 2.7.4 >> > > > > _______________________________________________ > kexec mailing list > kexec@xxxxxxxxxxxxxxxxxxx > http://lists.infradead.org/mailman/listinfo/kexec > _______________________________________________ kexec mailing list kexec@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/kexec