Willy Tarreau <w...@1wt.eu> writes: > On Sun, Aug 02, 2020 at 07:20:19PM +0200, Willy Tarreau wrote: >> On Sun, Aug 02, 2020 at 08:48:42PM +1000, Stephen Rothwell wrote: >> > Hi all, >> > >> > We are getting build failures in some PowerPC configs for Linus' tree. >> > See e.g. http://kisskb.ellerman.id.au/kisskb/buildresult/14306515/ >> > >> > In file included from /kisskb/src/arch/powerpc/include/asm/paca.h:18, >> > from /kisskb/src/arch/powerpc/include/asm/percpu.h:13, >> > from /kisskb/src/include/linux/random.h:14, >> > from /kisskb/src/include/linux/net.h:18, >> > from /kisskb/src/net/ipv6/ip6_fib.c:20: >> > /kisskb/src/arch/powerpc/include/asm/mmu.h:139:22: error: unknown type >> > name 'next_tlbcam_idx' >> > 139 | DECLARE_PER_CPU(int, next_tlbcam_idx); >> > >> > I assume this is caused by commit >> > >> > 1c9df907da83 ("random: fix circular include dependency on arm64 after >> > addition of percpu.h") >> > >> > But I can't see how, sorry. >> >> So there, asm/mmu.h includes asm/percpu.h, which includes asm/paca.h, which >> includes asm/mmu.h. >> >> I suspect that we can remove asm/paca.h from asm/percpu.h as it *seems* >> to be only used by the #define __my_cpu_offset but I don't know if anything >> will break further, especially if this __my_cpu_offset is used anywhere >> without this paca definition. > > I tried this and it fixed 5.8 for me with your config above. I'm appending > a patch that does just this. I didn't test other configs as I don't know > which ones to test though. If it fixes the problem for you, maybe it can > be picked by the PPC maintainers. > > Willy > From bcd64a7d0f3445c9a75d3b4dc4837d2ce61660c9 Mon Sep 17 00:00:00 2001 > From: Willy Tarreau <w...@1wt.eu> > Date: Mon, 3 Aug 2020 05:27:57 +0200 > Subject: powerpc: fix circular dependency in percpu.h > > After random.h started to include percpu.h (commit f227e3e), several > archs broke in circular dependencies around percpu.h. > > In https://lore.kernel.org/lkml/20200802204842.36bca...@canb.auug.org.au/ > Stephen Rothwell reported breakage for powerpc with CONFIG_PPC_FSL_BOOK3E. > > It turns out that asm/percpu.h includes asm/paca.h, which itself > includes mmu.h, which includes percpu.h when CONFIG_PPC_FSL_BOOK3E=y. > > Percpu seems to include asm/paca.h only for local_paca which is used in > the __my_cpu_offset macro. Removing this include solves the issue for > this config. > > Reported-by: Stephen Rothwell <s...@canb.auug.org.au> > Fixes: f227e3e ("random32: update the net random state on interrupt and > activity") > Link: https://lore.kernel.org/lkml/20200802204842.36bca...@canb.auug.org.au/ > Cc: Linus Torvalds <torva...@linux-foundation.org> > Cc: Michael Ellerman <m...@ellerman.id.au> > Cc: Benjamin Herrenschmidt <b...@kernel.crashing.org> > Cc: Paul Mackerras <pau...@samba.org> > Signed-off-by: Willy Tarreau <w...@1wt.eu> > --- > arch/powerpc/include/asm/percpu.h | 2 -- > 1 file changed, 2 deletions(-) > > diff --git a/arch/powerpc/include/asm/percpu.h > b/arch/powerpc/include/asm/percpu.h > index dce863a..cd3f6e5 100644 > --- a/arch/powerpc/include/asm/percpu.h > +++ b/arch/powerpc/include/asm/percpu.h > @@ -10,8 +10,6 @@ > > #ifdef CONFIG_SMP > > -#include <asm/paca.h> > - > #define __my_cpu_offset local_paca->data_offset > > #endif /* CONFIG_SMP */
If we just move the include of asm/paca.h below asm-generic/percpu.h then it avoids the bad circular dependency and we still have paca.h included from percpu.h as before. eg: diff --git a/arch/powerpc/include/asm/percpu.h b/arch/powerpc/include/asm/percpu.h index dce863a7635c..8e5b7d0b851c 100644 --- a/arch/powerpc/include/asm/percpu.h +++ b/arch/powerpc/include/asm/percpu.h @@ -10,8 +10,6 @@ #ifdef CONFIG_SMP -#include <asm/paca.h> - #define __my_cpu_offset local_paca->data_offset #endif /* CONFIG_SMP */ @@ -19,4 +17,6 @@ #include <asm-generic/percpu.h> +#include <asm/paca.h> + #endif /* _ASM_POWERPC_PERCPU_H_ */ So I think I'm inclined to merge that as a minimal fix that's easy to backport. cheers
