On Fri, Jun 23, 2023 at 10:17:54AM -0700, Nick Desaulniers wrote: > On Thu, Jun 22, 2023 at 11:18:03PM +0000, Nathan Chancellor wrote: > > If you wanted to restrict it to just LD_IS_BFD in arch/riscv/Kconfig, > > that would be fine with me too. > > > > select HAVE_LD_DEAD_CODE_DATA_ELIMINATION if LD_IS_BFD > > Hi Jisheng, would you mind sending a v3 with the attached patch applied > on top / at the end of your series? Hi Nick, Nathan, Palmer, I saw the series has been applied to riscv-next, so I'm not sure which solution would it be, Palmer to apply Nick's patch to riscv-next or I to send out v3, any suggestion is appreciated. Thanks > > > > > Nick said he would work on a report for the LLVM side, so as long as > > this issue is handled in some way to avoid regressing LLD builds until > > it is resolved, I don't think there is anything else for the kernel to > > do. We like to have breadcrumbs via issue links, not sure if the report > > will be internal to Google or on LLVM's issue tracker though; > > regardless, we will have to touch this block to add a version check > > later, at which point we can add a link to the fix in LLD. > > https://github.com/ClangBuiltLinux/linux/issues/1881 > From 3e5e010958ee41b9fb408cfade8fb017c2fe7169 Mon Sep 17 00:00:00 2001 > From: Nick Desaulniers <ndesaulniers@xxxxxxxxxx> > Date: Fri, 23 Jun 2023 10:06:17 -0700 > Subject: [PATCH] riscv: disable HAVE_LD_DEAD_CODE_DATA_ELIMINATION for LLD > > Linking allyesconfig with ld.lld-17 with CONFIG_DEAD_CODE_ELIMINATION=y > takes hours. Assuming this is a performance regression that can be > fixed, tentatively disable this for now so that allyesconfig builds > don't start timing out. If and when there's a fix to ld.lld, this can > be converted to a version check instead so that users of older but still > supported versions of ld.lld don't hurt themselves by enabling > CONFIG_LD_DEAD_CODE_DATA_ELIMINATION=y. > > Link: https://github.com/ClangBuiltLinux/linux/issues/1881 > Reported-by: Palmer Dabbelt <palmer@xxxxxxxxxxx> > Suggested-by: Nathan Chancellor <nathan@xxxxxxxxxx> > Signed-off-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx> > --- > Hi Jisheng, would you mind sending a v3 with this patch on top/at the > end of your patch series? > > arch/riscv/Kconfig | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig > index 8effe5bb7788..0573991e9b78 100644 > --- a/arch/riscv/Kconfig > +++ b/arch/riscv/Kconfig > @@ -116,7 +116,8 @@ config RISCV > select HAVE_KPROBES if !XIP_KERNEL > select HAVE_KPROBES_ON_FTRACE if !XIP_KERNEL > select HAVE_KRETPROBES if !XIP_KERNEL > - select HAVE_LD_DEAD_CODE_DATA_ELIMINATION > + # https://github.com/ClangBuiltLinux/linux/issues/1881 > + select HAVE_LD_DEAD_CODE_DATA_ELIMINATION if !LD_IS_LLD > select HAVE_MOVE_PMD > select HAVE_MOVE_PUD > select HAVE_PCI > -- > 2.41.0.162.gfafddb0af9-goog >
