Hi Atsushi, Thanks for the testing. On Wednesday 10 May 2017 01:37 PM, Atsushi Kumagai wrote: >> Hi Atsushi, >> >> On Friday 28 April 2017 12:22 PM, Atsushi Kumagai wrote: >>> Hello Pratyush, >>> >>> Thanks for your report, I have received this. >>> I'm on vacation until Mar 8, I'll review it when I return from vacation. >> >> Any further comment on it? >> Otherwise, I will send a v2 after accommodating concern from Xunlei. > > Unfortunately, it doesn't seem like I can make time anymore for review this week, > but at least this patch doesn't seem to work in my environment (linux 4.8 without kaslr). > Do you have any ideas ? I see, why it would have caused. I have not tested this case, but I hope my v2 should not have this issue. ~Pratyush > > > Program received signal SIGSEGV, Segmentation fault. > 0x00007ffff6be49f5 in fseek () from /lib64/libc.so.6 > Missing separate debuginfos, use: debuginfo-install bzip2-libs-1.0.6-13.el7.x86_64 elfutils-libelf-0.163-3.el7.x86_64 elfutils-libs-0.163-3.el7.x86_64 glibc-2.17-105.el7.x86_64 libgcc-4.8.5-4.el7.x86_64 libstdc++-4.8.5-4.el7.x86_64 snappy-1.1.0-3.el7.x86_64 xz-libs-5.1.2-12alpha.el7.x86_64 zlib-1.2.7-15.el7.x86_64 > (gdb) bt > #0 0x00007ffff6be49f5 in fseek () from /lib64/libc.so.6 > #1 0x0000000000429d38 in read_vmcoreinfo_symbol (str_symbol=0x44cb0c "SYMBOL(_stext)=") at makedumpfile.c:2384 > #2 0x000000000042097a in get_kaslr_offset_x86_64 (vaddr=18446744071589596288) at arch/x86_64.c:45 > #3 0x0000000000414310 in resolve_config_entry (ce=0x701370, base_vaddr=<optimized out>, base_struct_name=0x0) > at erase_info.c:1091 > #4 0x0000000000415a89 in get_config_symbol_addr (base_struct_name=0x0, base_vaddr=0, ce=0x701370) at erase_info.c:1264 > #5 update_filter_info (filter_symbol=0x701370, size_symbol=0x701430) at erase_info.c:1579 > #6 0x0000000000416543 in process_config (config=<optimized out>) at erase_info.c:1789 > #7 process_config_file (name_config=<optimized out>) at erase_info.c:1862 > #8 0x0000000000417c57 in gather_filter_info () at erase_info.c:2356 > #9 0x0000000000443ccb in create_dumpfile () at makedumpfile.c:9863 > #10 0x000000000044561e in main (argc=<optimized out>, argv=<optimized out>) at makedumpfile.c:11342 > (gdb) > > > Thanks, > Atsushi Kumagai > >> ~Pratyush >> >> >>> >>> Thanks, >>> Atsushi Kumagai >>> >>>> Hi All, >>>> >>>> We came across another failure in makedumpfile when kaslr is enabled. This >>>> failure occurs when we try re-filtering. We try to erase some symbol from a >>>> dumpfile which was copied/compressed from /proc/vmcore using makedumpfile. >>>> >>>> We have very limited symbol information in vmcoreinfo. So symbols to be >>>> erased may not be available in vmcoreinfo and we look for it in vmlinux. >>>> However, symbol address from vmlinux is a static address which differs >>> >from run time address with KASLR_OFFSET. Therefore, reading any "virtual >>>> address of vmlinux" from vmcore is not possible. >>>> >>>> These patches finds runtime KASLR offset and then calculates run time >>>> address of symbols read from vmlinux. >>>> >>>> Since, I am not an expert of x86, and these patches touch x86 part of >>>> makedumpfile, therefore I have CCed x86 experts. Please, provide your >>>> review comment and let me know if you think there could have been a better >>>> way to resolve this issue. >>>> >>>> thanks >>>> >>>> ~Pratyush >>>> >>>> Pratyush Anand (2): >>>> makedumpfile: add runtime kaslr offset if it exists >>>> x86_64: calculate page_offset in case of re-filtering >>>> >>>> arch/x86_64.c | 45 +++++++++++++++++++++++++++++++++++++++++++-- >>>> erase_info.c | 1 + >>>> makedumpfile.c | 44 ++++++++++++++++++++++++++++++++++++++++++++ >>>> makedumpfile.h | 15 +++++++++++++++ >>>> 4 files changed, 103 insertions(+), 2 deletions(-) >>>> >>>> -- >>>> 2.9.3 >>> > > > > _______________________________________________ > kexec mailing list > kexec at lists.infradead.org > http://lists.infradead.org/mailman/listinfo/kexec >
