Re: [Crash-utility] [PATCH] kernel: fix start-up time degradation caused by strings command

On Mon, Mar 28, 2022 at 9:57 PM Alexander Egorenkov <egorenar(a)linux.ibm.com&gt; wrote: > > > Where does the symbol '.rodata' come from ? > > I couldn't find it in x86's vmlinux with nm as well. > > > The "nm -a" option may be a good choice. > On Fedora 34: > > > > $ nm /usr/lib/debug/lib/modules/5.16.16-100.fc34.x86_64/vmlinux | grep > rodata > > ffffffff82c1d000 D __end_rodata > > ffffffff82e00000 D __end_rodata_aligned > > ffffffff82e00000 D __end_rodata_hpage_align > > ffffffff81199420 t frob_rodata > > ffffffff81c3eec7 T mark_rodata_ro > > ffffffff826dd200 D rodata_enabled > > ffffffff82e2cec0 d rodata_resource > > ffffffff81352690 T rodata_test > > ffffffff81c50238 t rodata_test.cold > > ffffffff8223d9d0 d rodata_test_data > > ffffffff836c2c36 t set_debug_rodata > > ffffffff838ff890 d __setup_set_debug_rodata > > ffffffff838b4b18 d __setup_str_set_debug_rodata > > ffffffff82200000 D __start_rodata > > > > Regards > > Alex > > Found the reason why all symbols starting with '.' are dropped for s390x > > /* > * Accept or reject a symbol from the kernel namelist. > */ > static int > s390x_verify_symbol(const char *name, ulong value, char type) > { > int i; > > ... > > /* throw away all symbols containing a '.' */ > for(i = 0; i < strlen(name);i++){ > if(name[i] == '.') <-------------- !!! > return FALSE; > } > > return TRUE; > } > > > But i have no idea why. Anybody familiar with this ? > I guess that it is to filter out some duplicated or unneeded symbols in crash-utility, especially for the old kernel. No more changelogs. Thanks. Lianbo > Thanks > Regards > Alex > > This Message Is From an External Sender This message came from outside your organization. On Mon, Mar 28, 2022 at 9:57 PM Alexander Egorenkov <egorenar(a)linux.ibm.com&gt; wrote: > Where does the symbol '.rodata' come from ? > I couldn't find it in x86's vmlinux with nm as well. > The "nm -a" option may be a good choice.

> On Fedora 34: > > $ nm /usr/lib/debug/lib/modules/5.16.16-100.fc34.x86_64/vmlinux | grep rodata > ffffffff82c1d000 D __end_rodata > ffffffff82e00000 D __end_rodata_aligned > ffffffff82e00000 D __end_rodata_hpage_align > ffffffff81199420 t frob_rodata > ffffffff81c3eec7 T mark_rodata_ro > ffffffff826dd200 D rodata_enabled > ffffffff82e2cec0 d rodata_resource > ffffffff81352690 T rodata_test > ffffffff81c50238 t rodata_test.cold > ffffffff8223d9d0 d rodata_test_data > ffffffff836c2c36 t set_debug_rodata > ffffffff838ff890 d __setup_set_debug_rodata > ffffffff838b4b18 d __setup_str_set_debug_rodata > ffffffff82200000 D __start_rodata > > Regards > Alex Found the reason why all symbols starting with '.' are dropped for s390x /* * Accept or reject a symbol from the kernel namelist. */ static int s390x_verify_symbol(const char *name, ulong value, char type) { int i; ... /* throw away all symbols containing a '.' */ for(i = 0; i < strlen(name);i++){ if(name[i] == '.') <-------------- !!! return FALSE; } return TRUE; } But i have no idea why. Anybody familiar with this ? I guess that it is to filter out some duplicated or unneeded symbols in crash-utility, especially for the old kernel. No more changelogs.