From: Michael Ellerman Date: Tue, 12 Feb 2013 14:44:50 +0000 (+0000) Subject: powerpc: Apply early paca fixups to boot_paca and the boot cpu's paca X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=25e138149c19fa0680147b825be475f5fd57f155;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git powerpc: Apply early paca fixups to boot_paca and the boot cpu's paca In commit 466921c we added a hack to set the paca data_offset to zero so that per-cpu accesses would work on the boot cpu prior to per-cpu areas being setup. This fixed a problem with lockdep touching per-cpu areas very early in boot. However if we combine CONFIG_LOCK_STAT=y with any of the PPC_EARLY_DEBUG options, we can hit the same problem in udbg_early_init(). To avoid that we need to set the data_offset of the boot_paca also. So factor out the fixup logic and call it for both the boot_paca, and "the paca of the boot cpu". Signed-off-by: Michael Ellerman Tested-by: Geoff Levand Signed-off-by: Benjamin Herrenschmidt --- diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c index f2514e13062b..75fbaceb5c87 100644 --- a/arch/powerpc/kernel/setup_64.c +++ b/arch/powerpc/kernel/setup_64.c @@ -156,6 +156,15 @@ early_param("smt-enabled", early_smt_enabled); #define check_smt_enabled() #endif /* CONFIG_SMP */ +/** Fix up paca fields required for the boot cpu */ +static void fixup_boot_paca(void) +{ + /* The boot cpu is started */ + get_paca()->cpu_start = 1; + /* Allow percpu accesses to work until we setup percpu data */ + get_paca()->data_offset = 0; +} + /* * Early initialization entry point. This is called by head.S * with MMU translation disabled. We rely on the "feature" of @@ -187,6 +196,7 @@ void __init early_setup(unsigned long dt_ptr) /* Assume we're on cpu 0 for now. Don't write to the paca yet! */ initialise_paca(&boot_paca, 0); setup_paca(&boot_paca); + fixup_boot_paca(); /* Initialize lockdep early or else spinlocks will blow */ lockdep_init(); @@ -207,11 +217,7 @@ void __init early_setup(unsigned long dt_ptr) /* Now we know the logical id of our boot cpu, setup the paca. */ setup_paca(&paca[boot_cpuid]); - - /* Fix up paca fields required for the boot cpu */ - get_paca()->cpu_start = 1; - /* Allow percpu accesses to "work" until we setup percpu data */ - get_paca()->data_offset = 0; + fixup_boot_paca(); /* Probe the machine type */ probe_machine();