| Message ID | 1580994807-88041-1-git-send-email-vladimir.murzin@arm.com |
|---|---|
| State | Accepted |
| Headers | show |
| Series | [uclibc-ng-devel] aarch64: always use MMU | expand |
Hi Vladimir, thanks, all four patches applied and pushed. Reduces the failure count for aarch64 testing to 3 from 34. best regards Waldemar Vladimir Murzin wrote, > Only MMU variant is supported. > > Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> > --- > extra/Configs/Config.aarch64 | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/extra/Configs/Config.aarch64 b/extra/Configs/Config.aarch64 > index cf1ce3b..d666cc5 100644 > --- a/extra/Configs/Config.aarch64 > +++ b/extra/Configs/Config.aarch64 > @@ -12,6 +12,7 @@ config FORCE_OPTIONS_FOR_ARCH > default y > select ARCH_ANY_ENDIAN > select ARCH_HAS_MMU > + select ARCH_USE_MMU > select UCLIBC_HAS_FPU > > choice > -- > 2.7.4 > > _______________________________________________ > devel mailing list > devel@uclibc-ng.org > https://mailman.uclibc-ng.org/cgi-bin/mailman/listinfo/devel
Hi, Vladimir Murzin wrote, > Hi Waldemar, > > On 2/7/20 1:40 PM, Waldemar Brodkorb wrote: > > Hi Vladimir, > > > > thanks, all four patches applied and pushed. > > Reduces the failure count for aarch64 testing to 3 from > > 34. > > Great! > > May I know which are failing test so I might have a look when I > get enough bandwidth? These are the open failures: .... tst-tls17^MFAIL tst-tls17 got 1 expected 0 Didn't expect signal from child: got `Segmentation fault' .... tst-tls18^MFAIL tst-tls18 got 1 expected 0 Didn't expect signal from child: got `Segmentation fault' .... tst-res^MFAIL tst-res got 139 expected 0 Segmentation fault best regards Waldemar
Hi Waldemar, On 2/7/20 1:40 PM, Waldemar Brodkorb wrote: > Hi Vladimir, > > thanks, all four patches applied and pushed. > Reduces the failure count for aarch64 testing to 3 from > 34. Great! May I know which are failing test so I might have a look when I get enough bandwidth? Cheers Vladimir > > best regards > Waldemar > > Vladimir Murzin wrote, > >> Only MMU variant is supported. >> >> Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> >> --- >> extra/Configs/Config.aarch64 | 1 + >> 1 file changed, 1 insertion(+) >> >> diff --git a/extra/Configs/Config.aarch64 b/extra/Configs/Config.aarch64 >> index cf1ce3b..d666cc5 100644 >> --- a/extra/Configs/Config.aarch64 >> +++ b/extra/Configs/Config.aarch64 >> @@ -12,6 +12,7 @@ config FORCE_OPTIONS_FOR_ARCH >> default y >> select ARCH_ANY_ENDIAN >> select ARCH_HAS_MMU >> + select ARCH_USE_MMU >> select UCLIBC_HAS_FPU >> >> choice >> -- >> 2.7.4 >> >> _______________________________________________ >> devel mailing list >> devel@uclibc-ng.org >> https://mailman.uclibc-ng.org/cgi-bin/mailman/listinfo/devel >
Hi Waldemar, On 2/7/20 1:51 PM, Waldemar Brodkorb wrote: > Hi, > Vladimir Murzin wrote, > >> Hi Waldemar, >> >> On 2/7/20 1:40 PM, Waldemar Brodkorb wrote: >>> Hi Vladimir, >>> >>> thanks, all four patches applied and pushed. >>> Reduces the failure count for aarch64 testing to 3 from >>> 34. >> >> Great! >> >> May I know which are failing test so I might have a look when I >> get enough bandwidth? > > These are the open failures: > > .... tst-tls17^MFAIL tst-tls17 got 1 expected 0 > Didn't expect signal from child: got `Segmentation fault' > .... tst-tls18^MFAIL tst-tls18 got 1 expected 0 > Didn't expect signal from child: got `Segmentation fault' > .... tst-res^MFAIL tst-res got 139 expected 0 > Segmentation fault > > I got some time to look into it. I took tst-tls17 and this is how it fails (gdb) disassemble Dump of assembler code for function tlsmod17a0: 0x0000fffff7f1a710 <+0>: stp x29, x30, [sp, #-16]! 0x0000fffff7f1a714 <+4>: mrs x2, tpidr_el0 0x0000fffff7f1a718 <+8>: adrp x0, 0xfffff7f2b000 0x0000fffff7f1a71c <+12>: ldr x1, [x0, #32] 0x0000fffff7f1a720 <+16>: add x0, x0, #0x20 0x0000fffff7f1a724 <+20>: blr x1 0x0000fffff7f1a728 <+24>: mov x29, sp 0x0000fffff7f1a72c <+28>: add x2, x2, x0 0x0000fffff7f1a730 <+32>: cbz x2, 0xfffff7f1a744 <tlsmod17a0+52> => 0x0000fffff7f1a734 <+36>: ldr w1, [x2] 0x0000fffff7f1a738 <+40>: mov w0, #0x0 // #0 0x0000fffff7f1a73c <+44>: cmp w1, #0x4 0x0000fffff7f1a740 <+48>: b.eq 0xfffff7f1a758 <tlsmod17a0+72> // b.none 0x0000fffff7f1a744 <+52>: adrp x0, 0xfffff7f1a000 0x0000fffff7f1a748 <+56>: mov w1, #0x0 // #0 0x0000fffff7f1a74c <+60>: add x0, x0, #0x770 0x0000fffff7f1a750 <+64>: bl 0xfffff7f1a5a0 <printf@plt> 0x0000fffff7f1a754 <+68>: mov w0, #0x1 // #1 0x0000fffff7f1a758 <+72>: ldp x29, x30, [sp], #16 0x0000fffff7f1a75c <+76>: ret End of assembler dump. (gdb) i r x2 x2 0x1ffffeff14c18 562949684022296 As you can see address stored in x2 is odd. It seems that is due to how x0 was computed: (gdb) x/2xg 0xfffff7f2b000+32 0xfffff7f2b020: 0x0000fffff7fed028 0x0000fffff7f1a558 (gdb) disassemble 0x0000fffff7fed028 Dump of assembler code for function _dl_tlsdesc_return: 0x0000fffff7fed028 <+0>: ldr x0, [x0, #8] 0x0000fffff7fed02c <+4>: ret End of assembler dump. since _dl_tlsdesc_return() takes tlsdesc I started looking how that was filled. In this particular case it comes from _dl_do_lazy_reloc(): v0 value=0x0 size=0x4 info=0x16 other=0x0 shndx=0xe 0x407 offset=0x11020 addend=0x0 patched_lazy: 0x0 ==> 0xffffa8dc7028 @ 0xffffa8d05020 yet value stored in arg member of tlsdesc is bogus due to case R_AARCH64_TLSDESC: { struct tlsdesc volatile *td = (struct tlsdesc volatile *)reloc_addr; td->arg = (void*)rpnt; td->entry = _dl_tlsdesc_return; } break; i.e. it holds address of Elf64_Rela object. In contrast glibc holds relatively small number (0xed or so). Next I started wondering how to fix that and hit [1] - it seems that uClibc also affected, yet next I hit [2] and now I dunno if it worth fixing... It looks like the proper fix would be disable lazy tlsdesc, but I'm not familiar enough with the code to do it on my own. [1] https://sourceware.org/legacy-ml/libc-alpha/2015-04/msg00266.html [2] https://sourceware.org/legacy-ml/libc-alpha/2017-10/msg01117.html Cheers Vladimir
diff --git a/extra/Configs/Config.aarch64 b/extra/Configs/Config.aarch64 index cf1ce3b..d666cc5 100644 --- a/extra/Configs/Config.aarch64 +++ b/extra/Configs/Config.aarch64 @@ -12,6 +12,7 @@ config FORCE_OPTIONS_FOR_ARCH default y select ARCH_ANY_ENDIAN select ARCH_HAS_MMU + select ARCH_USE_MMU select UCLIBC_HAS_FPU choice
Only MMU variant is supported. Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> --- extra/Configs/Config.aarch64 | 1 + 1 file changed, 1 insertion(+)