From 6259f3443c6a376aa077816ac92e9ddeb0817d09 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Mon, 3 Jul 2023 19:31:26 +0100 Subject: [PATCH] risc-v: Fix order of IPI enablement vs RCU startup Conor reports that risc-v tries to enable IPIs before telling the core code to enable RCU. With the introduction of the mapple tree as a backing store for the irq descriptors, this results in a very shouty boot sequence, as RCU is legitimately upset. Restore some sanity by moving the risc_ipi_enable() call after notify_cpu_starting(), which explicitly enables RCU on the calling CPU. Fixes: 832f15f42646 ("RISC-V: Treat IPIs as normal Linux IRQs") Reported-by: Conor Dooley Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20230703-dupe-frying-79ae2ccf94eb@spud Cc: Anup Patel Cc: Palmer Dabbelt Cc: Linus Torvalds Tested-by: Conor Dooley Link: https://lore.kernel.org/r/20230703183126.1567625-1-maz@kernel.org Signed-off-by: Palmer Dabbelt --- arch/riscv/kernel/smpboot.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/riscv/kernel/smpboot.c b/arch/riscv/kernel/smpboot.c index bb0b76e..f4d6acb 100644 --- a/arch/riscv/kernel/smpboot.c +++ b/arch/riscv/kernel/smpboot.c @@ -238,10 +238,11 @@ asmlinkage __visible void smp_callin(void) mmgrab(mm); current->active_mm = mm; - riscv_ipi_enable(); - store_cpu_topology(curr_cpuid); notify_cpu_starting(curr_cpuid); + + riscv_ipi_enable(); + numa_add_cpu(curr_cpuid); set_cpu_online(curr_cpuid, 1); probe_vendor_features(curr_cpuid); -- 2.7.4