On Wed, Oct 3, 2018 at 2:12 AM Burton, Ross <[email protected]> wrote: > > Perfect. :) Did you file a bug upstream, or shall I copy/paste that > into a bug now?
i did not. thanks in advance if you can > > Ross > On Wed, 3 Oct 2018 at 01:49, Khem Raj <[email protected]> wrote: > > > > Musl started blocking dlopen of libs with initial-exec references into > > dynamic TLS area, via > > > > https://github.com/kraj/musl/commit/5c2f46a214fceeee3c3e41700c51415e0a4f1acd > > > > prior to that commit, musl was loading it and silently letting > > subsequent TLS accesses via the miscompiled code clobber memory that > > didn't belong to them > > > > This was wrong behavior and it relied on additional space reserved by > > libc in TLS space to adjust fo such broken libs, but it also fails > > with glibc if the reserved space was already used up > > > > Right fix is that mesa should be patched to remove all the > > initial-exec hacks and use real TLS, and -mtls-dialect=gnu2 (TLSDESC) > > should be used on archs it's supported on (i386, x86_64, and aarch64) > > to make up for the lost performance, but mesa hardcodes the initial-exec, > > so there must be a reason that probably is better known to mesa devs. > > > > but we 'fixed' it for musl by adding --disable-glx-tls for mesa in OE, > > which uses pthread_getspecific instead and makes is lot slower. > > > > this caused additional problems with security flags on, it get textrels > > in .text segment. Therefore this is 'second fix' to get us through this > > warning. > > > > Cause is some unknown part of mesa's x86 assembly code is broken by > > readonly text segments > > > > [ YOCTO #12918 ] > > > > Signed-off-by: Khem Raj <[email protected]> > > --- > > V3: Disable asm just on x86, since it works well elsewhere > > > > meta/recipes-graphics/mesa/mesa.inc | 2 ++ > > 1 file changed, 2 insertions(+) > > > > diff --git a/meta/recipes-graphics/mesa/mesa.inc > > b/meta/recipes-graphics/mesa/mesa.inc > > index 8d0e2cb67c..0dfdfbd5b4 100644 > > --- a/meta/recipes-graphics/mesa/mesa.inc > > +++ b/meta/recipes-graphics/mesa/mesa.inc > > @@ -108,6 +108,8 @@ PACKAGECONFIG[unwind] = > > "--enable-libunwind,--disable-libunwind,libunwind" > > > > EXTRA_OECONF_remove_libc-musl = "--enable-glx-tls" > > EXTRA_OECONF_append_libc-musl = " --disable-glx-tls" > > +EXTRA_OECONF_append_libc-musl_x86 = " --disable-asm" > > + > > # llvmpipe is slow if compiled with -fomit-frame-pointer (e.g. -O2) > > FULL_OPTIMIZATION_append = " -fno-omit-frame-pointer" > > > > -- > > 2.19.0 > > > > -- > > _______________________________________________ > > Openembedded-core mailing list > > [email protected] > > http://lists.openembedded.org/mailman/listinfo/openembedded-core -- _______________________________________________ Openembedded-core mailing list [email protected] http://lists.openembedded.org/mailman/listinfo/openembedded-core
