Re: [GIT PULL] Please pull powerpc/linux.git powerpc-5.3-4 tag
[ expanded Cc ] Linus Torvalds writes: > On Sat, Aug 10, 2019 at 3:11 AM Michael Ellerman wrote: >> >> Just one fix, a revert of a commit that was meant to be a minor improvement >> to >> some inline asm, but ended up having no real benefit with GCC and broke >> booting >> 32-bit machines when using Clang. > > Pulled, but whenever there are possible subtle compiler issues I get > nervous, and wonder if the problem was reported to the clang guys? Yes, sorry I should have included more context. It was actually the Clang Linux folks who noticed it and reported it to us: https://github.com/ClangBuiltLinux/linux/issues/593 There's an LLVM bug filed: https://bugs.llvm.org/show_bug.cgi?id=42762 And I think there's now agreement that the Clang behaviour is not correct, Nick actually sent a revert as well but I already had one queued: https://patchwork.ozlabs.org/patch/1144980/ Arnd identified some work arounds, which we may end up using, but for this cycle we thought it was preferable to just revert this change as it didn't actually change code generation with GCC anyway. cheers
Re: [GIT PULL] Please pull powerpc/linux.git powerpc-5.3-4 tag
On Sat, Aug 10, 2019 at 10:21:01AM -0700, Linus Torvalds wrote: > On Sat, Aug 10, 2019 at 3:11 AM Michael Ellerman wrote: > > > > Just one fix, a revert of a commit that was meant to be a minor improvement > > to > > some inline asm, but ended up having no real benefit with GCC and broke > > booting > > 32-bit machines when using Clang. > > Pulled, but whenever there are possible subtle compiler issues I get > nervous, and wonder if the problem was reported to the clang guys? > > In particular, if the kernel change was technically correct, maybe > somebody else comes along in a few years and tries the same, and then > it's another odd "why doesn't this work for person X when it works > just fine for me".. > > Linus It was. https://github.com/ClangBuiltLinux/linux/issues/593 https://bugs.llvm.org/show_bug.cgi?id=42762 We're still waiting for input from the PowerPC backend maintainers as that is most likely where this issue originates from. Cheers, Nathan
Re: [GIT PULL] Please pull powerpc/linux.git powerpc-5.3-4 tag
The pull request you sent on Sat, 10 Aug 2019 20:11:49 +1000: > https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git > tags/powerpc-5.3-4 has been merged into torvalds/linux.git: https://git.kernel.org/torvalds/c/23df57afe8eebff6ece05a815934f2f70a851e0a Thank you! -- Deet-doot-dot, I am a bot. https://korg.wiki.kernel.org/userdoc/prtracker
Re: [GIT PULL] Please pull powerpc/linux.git powerpc-5.3-4 tag
On Sat, Aug 10, 2019 at 3:11 AM Michael Ellerman wrote: > > Just one fix, a revert of a commit that was meant to be a minor improvement to > some inline asm, but ended up having no real benefit with GCC and broke > booting > 32-bit machines when using Clang. Pulled, but whenever there are possible subtle compiler issues I get nervous, and wonder if the problem was reported to the clang guys? In particular, if the kernel change was technically correct, maybe somebody else comes along in a few years and tries the same, and then it's another odd "why doesn't this work for person X when it works just fine for me".. Linus
