[Crash-utility] Re: [PATCH 0/3] Several fixes for v6.14-rc kernels

Hi Tao, Lianbo, Thank you for the fixes. I also hit the issue [3] and not sure how it can be fixed, sharing a bit of information. It looks like the xen_elfnote_phys32_entry_value is not offset with KASLR offset and not sorted too.

crash> sym -l ... ffffffff9b030000 (B) _end ffffffff9b200000 (d) .init.scratch ffffffff9b200000 (D) __init_scratch_begin ffffffff9b200000 (d) sme_workarea ffffffff9b600000 (D) __init_scratch_end ffffffff846d4fbc (A) xen_elfnote_phys32_entry_value <<--- ffffffffc038d000 MODULE TEXT START: dm_mod ffffffffc038d000 (T) __pfx_dm_send_uevents ffffffffc038d010 (T) dm_send_uevents ffffffffc038d1a0 (T) __pfx_dm_path_uevent $ readelf -s vmlinux | grep xen_elfnote 213406: ffffffff827d004c 0 NOTYPE GLOBAL DEFAULT 15 xen_elfnote_phys32_entry 221196: ffffffff846d4fbc 0 NOTYPE GLOBAL DEFAULT ABS xen_elfnote_phys32_entry_ ^^^^^^^^^^^^^^^^ so when the KASLR offset is large enough, all of kernel symbols are considered as out of kernel symbol range. crash> sym schedule ffffffff992f6c00 (T) schedule /home/kernel/linux-6.14-rc1-localmod/kernel/sched/core.c: 6847 crash> sym ffffffff992f6c00 sym: invalid address: ffffffff992f6c00 I'm not sure whether it should be re-sorted.. because if we resort it, the symbol can become lower than _stext, is it ok? btw, what is the symbol? why isn't it offset? Thanks, Kazu On 2025/02/25 6:19, Tao Liu wrote: > Hi Lianbo, > > On Mon, Feb 24, 2025 at 10:03 PM lijiang <lijiang(a)redhat.com&gt; wrote: >> >> Thank you for the fix, Tao. >> >> On Mon, Feb 24, 2025 at 11:02 AM <devel-request(a)lists.crash-utility.osci.io&gt; wrote: >>> >>> Date: Mon, 24 Feb 2025 15:59:11 +1300 >>> From: Tao Liu <ltao(a)redhat.com&gt; >>> Subject: [Crash-utility] [PATCH 0/3] Several fixes for v6.14-rc >>> kernels >>> To: devel(a)lists.crash-utility.osci.io >>> Cc: andersonc0d3(a)gmail.com, Tao Liu <ltao(a)redhat.com&gt; >>> Message-ID: <20250224025914.16044-1-ltao(a)redhat.com&gt; >>> Content-Type: text/plain; charset="US-ASCII"; x-default=true >>> >>> There are a few failing cases observed on v6.14-rc kernel. This patchset >>> will fix these. >>> >>> For the NO.1 patch, Anderson used "vtop" cmd as the test case [1], which I >>> cannot reproduce because I didn't find a suitable value for vtop to >>> trigger the failing. So I switched to "files" cmd. >>> >>> [1]: https://www.mail-archive.com/devel@lists.crash-utility.osci.io/msg01356.html >>> >>> Tao Liu (3): >>> Fix the failing of cmd "files" for v6.14-rc1 kernel >>> Fix the failing of cmd "runq -g" for v6.14-rc1 kernel >> >> >> The patch [1] and [2] are fine to me, applied: >> [1] https://github.com/crash-utility/crash/commit/2795136a515446b798ebbfa257c... >> [2] https://github.com/crash-utility/crash/commit/080b4baf5d5e998750f80289c84... >> > Thanks for applying the patches. > >>> Sort the symtable at the end of store_symbols() >>> >> >> For the patch [3], I did not reproduce the current issue, can you try to provide some unsorted symbols information? >> > Sure, this is the st->symtable at the end of function store_symbols() > without the NO.3 patch: > > (gdb) p/x st->symtable[st->symcnt-1] > $13 = {value = 0xffffffff853da7f4, name = 0x1e75ae4, val_hash_next = > 0x0, name_hash_next = 0x0, type = 0x41, cnt = 0x0, flags = 0x0, > pad2 = 0x0} > (gdb) x/s st->symtable[st->symcnt-1].name > 0x1e75ae4: "xen_elfnote_phys32_entry_value" > (gdb) p/x st->symtable[st->symcnt-2] > $14 = {value = 0xffffffff99a00000, name = 0x1e75ad1, val_hash_next = > 0x0, name_hash_next = 0x0, type = 0x44, cnt = 0x0, flags = 0x0, > pad2 = 0x0} > (gdb) x/s st->symtable[st->symcnt-2].name > 0x1e75ad1: "__init_scratch_end" > (gdb) p/x st->symtable[st->symcnt-3] > $15 = {value = 0xffffffff99600000, name = 0x1e75ac4, val_hash_next = > 0x0, name_hash_next = 0x0, type = 0x64, cnt = 0x0, flags = 0x0, > pad2 = 0x0} > (gdb) x/s st->symtable[st->symcnt-3].name > 0x1e75ac4: "sme_workarea" > (gdb) p/x st->symtable[st->symcnt-4] > $16 = {value = 0xffffffff99600000, name = 0x1e75aaf, val_hash_next = > 0x0, name_hash_next = 0x0, type = 0x44, cnt = 0x0, flags = 0x0, > pad2 = 0x0} > (gdb) x/s st->symtable[st->symcnt-4].name > 0x1e75aaf: "__init_scratch_begin" > > The "st->symcnt-1" one is the last element of st->symtable, and should > have the highest value. However it is not. > >> Maybe there are similar cases such as store_sysmap_symbols. > > I think we don't need a re-sort for store_sysmap_symbols(), because > the symbols read by store_sysmap_symbols() is from System.map file, > which already have the symbols sorted by default. > > Thanks, > Tao Liu > >> >> >> Thanks >> Lianbo >> >>> >>> filesys.c | 3 +++ >>> symbols.c | 3 +++ >>> task.c | 3 +++ >>> 3 files changed, 9 insertions(+) >>> >>> -- >>> 2.47.0 > -- > Crash-utility mailing list -- devel(a)lists.crash-utility.osci.io > To unsubscribe send an email to devel-leave(a)lists.crash-utility.osci.io > https://${domain_name}/admin/lists/devel.lists.crash-utility.osci.io/ > Contribution Guidelines: https://github.com/crash-utility/crash/wiki