From: Nicholas Piggin Date: Mon, 26 Sep 2022 05:56:19 +0000 (+1000) Subject: powerpc/64: don't set boot CPU's r13 to paca until the structure is set up X-Git-Tag: v6.1-rc1~103^2~39 X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=519b2e317e39ac99ce589a7c8480c47a17d62638;p=users%2Fdwmw2%2Flinux.git powerpc/64: don't set boot CPU's r13 to paca until the structure is set up The idea is to get to the point where if r13 is non-zero, then it should contain a reasonable paca. This can be used in early boot program check and machine check handlers to avoid running off into the weeds if they hit before r13 has a paca. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220926055620.2676869-5-npiggin@gmail.com --- diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c index f50476da2f2cc..6312a3fe8eff9 100644 --- a/arch/powerpc/kernel/setup_64.c +++ b/arch/powerpc/kernel/setup_64.c @@ -177,10 +177,10 @@ early_param("smt-enabled", early_smt_enabled); #endif /* CONFIG_SMP */ /** Fix up paca fields required for the boot cpu */ -static void __init fixup_boot_paca(void) +static void __init fixup_boot_paca(struct paca_struct *boot_paca) { /* The boot cpu is started */ - get_paca()->cpu_start = 1; + boot_paca->cpu_start = 1; #ifdef CONFIG_PPC_BOOK3S_64 /* * Give the early boot machine check stack somewhere to use, use @@ -188,14 +188,14 @@ static void __init fixup_boot_paca(void) * deep stack usage in early init so shouldn't overflow it or overwrite * things. */ - get_paca()->mc_emergency_sp = (void *)&init_thread_union + + boot_paca->mc_emergency_sp = (void *)&init_thread_union + (THREAD_SIZE/2); #endif /* Allow percpu accesses to work until we setup percpu data */ - get_paca()->data_offset = 0; + boot_paca->data_offset = 0; /* Mark interrupts soft and hard disabled in PACA */ - irq_soft_mask_set(IRQS_DISABLED); - get_paca()->irq_happened = PACA_IRQ_HARD_DIS; + boot_paca->irq_soft_mask = IRQS_DISABLED; + boot_paca->irq_happened = PACA_IRQ_HARD_DIS; WARN_ON(mfmsr() & MSR_EE); } @@ -363,8 +363,8 @@ void __init early_setup(unsigned long dt_ptr) * what CPU we are on. */ initialise_paca(&boot_paca, 0); - setup_paca(&boot_paca); - fixup_boot_paca(); + fixup_boot_paca(&boot_paca); + setup_paca(&boot_paca); /* install the paca into registers */ /* -------- printk is now safe to use ------- */ @@ -393,8 +393,8 @@ void __init early_setup(unsigned long dt_ptr) /* Poison paca_ptrs[0] again if it's not the boot cpu */ memset(&paca_ptrs[0], 0x88, sizeof(paca_ptrs[0])); } - setup_paca(paca_ptrs[boot_cpuid]); - fixup_boot_paca(); + fixup_boot_paca(paca_ptrs[boot_cpuid]); + setup_paca(paca_ptrs[boot_cpuid]); /* install the paca into registers */ /* * Configure exception handlers. This include setting up trampolines