diff options
| -rw-r--r-- | arch/powerpc/kernel/dt_cpu_ftrs.c | 1 | ||||
| -rw-r--r-- | arch/powerpc/kernel/paca.c | 10 | ||||
| -rw-r--r-- | arch/powerpc/kernel/setup_64.c | 30 |
3 files changed, 31 insertions, 10 deletions
diff --git a/arch/powerpc/kernel/dt_cpu_ftrs.c b/arch/powerpc/kernel/dt_cpu_ftrs.c index 182b4047c1ef..36bc0d5c4f3a 100644 --- a/arch/powerpc/kernel/dt_cpu_ftrs.c +++ b/arch/powerpc/kernel/dt_cpu_ftrs.c @@ -139,7 +139,6 @@ static void __init cpufeatures_setup_cpu(void) /* Initialize the base environment -- clear FSCR/HFSCR. */ hv_mode = !!(mfmsr() & MSR_HV); if (hv_mode) { - /* CPU_FTR_HVMODE is used early in PACA setup */ cur_cpu_spec->cpu_features |= CPU_FTR_HVMODE; mtspr(SPRN_HFSCR, 0); } diff --git a/arch/powerpc/kernel/paca.c b/arch/powerpc/kernel/paca.c index 949eceb254d8..0ee6308541b1 100644 --- a/arch/powerpc/kernel/paca.c +++ b/arch/powerpc/kernel/paca.c @@ -214,11 +214,15 @@ void setup_paca(struct paca_struct *new_paca) /* On Book3E, initialize the TLB miss exception frames */ mtspr(SPRN_SPRG_TLB_EXFRAME, local_paca->extlb); #else - /* In HV mode, we setup both HPACA and PACA to avoid problems + /* + * In HV mode, we setup both HPACA and PACA to avoid problems * if we do a GET_PACA() before the feature fixups have been - * applied + * applied. + * + * Normally you should test against CPU_FTR_HVMODE, but CPU features + * are not yet set up when we first reach here. */ - if (early_cpu_has_feature(CPU_FTR_HVMODE)) + if (mfmsr() & MSR_HV) mtspr(SPRN_SPRG_HPACA, local_paca); #endif mtspr(SPRN_SPRG_PACA, local_paca); diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c index e05e6dd67ae6..17886d147dd0 100644 --- a/arch/powerpc/kernel/setup_64.c +++ b/arch/powerpc/kernel/setup_64.c @@ -285,18 +285,36 @@ void __init early_setup(unsigned long dt_ptr) /* -------- printk is _NOT_ safe to use here ! ------- */ - /* Try new device tree based feature discovery ... */ - if (!dt_cpu_ftrs_init(__va(dt_ptr))) - /* Otherwise use the old style CPU table */ - identify_cpu(0, mfspr(SPRN_PVR)); - - /* Assume we're on cpu 0 for now. Don't write to the paca yet! */ + /* + * Assume we're on cpu 0 for now. + * + * We need to load a PACA very early for a few reasons. + * + * The stack protector canary is stored in the paca, so as soon as we + * call any stack protected code we need r13 pointing somewhere valid. + * + * If we are using kcov it will call in_task() in its instrumentation, + * which relies on the current task from the PACA. + * + * dt_cpu_ftrs_init() calls into generic OF/fdt code, as well as + * printk(), which can trigger both stack protector and kcov. + * + * percpu variables and spin locks also use the paca. + * + * So set up a temporary paca. It will be replaced below once we know + * what CPU we are on. + */ initialise_paca(&boot_paca, 0); setup_paca(&boot_paca); fixup_boot_paca(); /* -------- printk is now safe to use ------- */ + /* Try new device tree based feature discovery ... */ + if (!dt_cpu_ftrs_init(__va(dt_ptr))) + /* Otherwise use the old style CPU table */ + identify_cpu(0, mfspr(SPRN_PVR)); + /* Enable early debugging if any specified (see udbg.h) */ udbg_early_init(); |