From: Christophe Leroy <christophe.leroy@c-s.fr> To: Benjamin Herrenschmidt <benh@kernel.crashing.org>, Paul Mackerras <paulus@samba.org>, Michael Ellerman <mpe@ellerman.id.au>, Chris Packham <Chris.Packham@alliedtelesis.co.nz> Cc: linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org Subject: [PATCH] powerpc/64e: drop stale call to smp_processor_id() which hangs SMP startup Date: Thu, 8 Aug 2019 12:48:26 +0000 (UTC) Message-ID: <bef479514f4c08329fa649f67735df8918bc0976.1565268248.git.christophe.leroy@c-s.fr> (raw) Santa commit ebb9d30a6a74 ("powerpc/mm: any thread in one core can be the first to setup TLB1") removed the need to know the cpu_id in early_init_this_mmu(), but the call to smp_processor_id() which was marked __maybe_used remained. Since commit ed1cd6deb013 ("powerpc: Activate CONFIG_THREAD_INFO_IN_TASK") thread_info cannot be reached before mmu is properly set up. Drop this stale call to smp_processor_id() which make SMP hang when CONFIG_PREEMPT is set. Reported-by: Chris Packham <Chris.Packham@alliedtelesis.co.nz> Fixes: ebb9d30a6a74 ("powerpc/mm: any thread in one core can be the first to setup TLB1") Link: https://github.com/linuxppc/issues/issues/264 Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Cc: stable@vger.kernel.org --- arch/powerpc/mm/nohash/tlb.c | 1 - 1 file changed, 1 deletion(-) diff --git a/arch/powerpc/mm/nohash/tlb.c b/arch/powerpc/mm/nohash/tlb.c index d4acf6fa0596..bf60983a58c7 100644 --- a/arch/powerpc/mm/nohash/tlb.c +++ b/arch/powerpc/mm/nohash/tlb.c @@ -630,7 +630,6 @@ static void early_init_this_mmu(void) #ifdef CONFIG_PPC_FSL_BOOK3E if (mmu_has_feature(MMU_FTR_TYPE_FSL_E)) { unsigned int num_cams; - int __maybe_unused cpu = smp_processor_id(); bool map = true; /* use a quarter of the TLBCAM for bolted linear map */ -- 2.13.3
next reply index Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top 2019-08-08 12:48 Christophe Leroy [this message] 2019-08-08 21:12 ` Chris Packham 2019-08-12 13:15 ` Michael Ellerman
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