Hi Michael,
Le 03/11/2020 à 19:13, Christophe Leroy a écrit :
Le 23/10/2020 à 15:24, Michael Ellerman a écrit :
Christophe Leroy <christophe.le...@csgroup.eu> writes:
Le 24/09/2020 à 15:17, Christophe Leroy a écrit :
Le 17/09/2020 à 14:33, Michael Ellerman a écrit :
Christophe Leroy <christophe.le...@csgroup.eu> writes:
What is the status with the generic C vdso merge ?
In some mail, you mentionned having difficulties getting it working on
ppc64, any progress ? What's the problem ? Can I help ?
Yeah sorry I was hoping to get time to work on it but haven't been able
to.
It's causing crashes on ppc64 ie. big endian.
...
Can you tell what defconfig you are using ? I have been able to setup a full
glibc PPC64 cross
compilation chain and been able to test it under QEMU with success, using
Nathan's vdsotest tool.
What config are you using ?
ppc64_defconfig + guest.config
Or pseries_defconfig.
I'm using Ubuntu GCC 9.3.0 mostly, but it happens with other toolchains too.
At a minimum we're seeing relocations in the output, which is a problem:
$ readelf -r build\~/arch/powerpc/kernel/vdso64/vdso64.so
Relocation section '.rela.dyn' at offset 0x12a8 contains 8 entries:
Offset Info Type Sym. Value Sym. Name +
Addend
000000001368 000000000016 R_PPC64_RELATIVE 7c0
000000001370 000000000016 R_PPC64_RELATIVE 9300
000000001380 000000000016 R_PPC64_RELATIVE 970
000000001388 000000000016 R_PPC64_RELATIVE 9300
000000001398 000000000016 R_PPC64_RELATIVE a90
0000000013a0 000000000016 R_PPC64_RELATIVE 9300
0000000013b0 000000000016 R_PPC64_RELATIVE b20
0000000013b8 000000000016 R_PPC64_RELATIVE 9300
Looks like it's due to the OPD and relation between the function() and
.function()
By using DOTSYM() in the 'bl' call, that's directly the dot function which is called and the OPD is
not used anymore, it can get dropped.
Now I get .rela.dyn full of 0, don't know if we should drop it explicitely.
What is the status now with latest version of CVDSO ? I saw you had it in next-test for some time,
it is not there anymore today.
Thanks,
Christophe
