[PATCH] kvm: powerpc: book3s: use local_paca instead of get_paca

[Denis Kirjanov]

On 3/29/17, Denis Kirjanov <kda at linux-powerpc.org> wrote:
> with CONFIG_DEBUG_PREEMPT get_paca produces the following warning
> in kvmppc_book3s_init_hv since we are getting into the
> smp_processor_id debugging code
>
> There is no real issue with the xics_phys field.
> If paca->kvm_hstate.xics_phys is non-zero on one cpu, it will be
> non-zero on them all.  Therefore this is not fixing any actual
> problem, just the warning.

Hey Michael,

are you going to take the patch?

Thanks!
>
> [  138.521188] BUG: using smp_processor_id() in preemptible [00000000] code:
> modprobe/5596
> [  138.521308] caller is .kvmppc_book3s_init_hv+0x184/0x350 [kvm_hv]
> [  138.521404] CPU: 5 PID: 5596 Comm: modprobe Not tainted
> 4.11.0-rc3-00022-gc7e790c #1
> [  138.521509] Call Trace:
> [  138.521563] [c0000007d018b810] [c0000000023eef10] .dump_stack+0xe4/0x150
> (unreliable)
> [  138.521694] [c0000007d018b8a0] [c000000001f6ec04]
> .check_preemption_disabled+0x134/0x150
> [  138.521829] [c0000007d018b940] [d00000000a010274]
> .kvmppc_book3s_init_hv+0x184/0x350 [kvm_hv]
> [  138.521963] [c0000007d018ba00] [c00000000191d5cc]
> .do_one_initcall+0x5c/0x1c0
> [  138.522082] [c0000007d018bad0] [c0000000023e9494]
> .do_init_module+0x84/0x240
> [  138.522201] [c0000007d018bb70] [c000000001aade18]
> .load_module+0x1f68/0x2a10
> [  138.522319] [c0000007d018bd20] [c000000001aaeb30]
> .SyS_finit_module+0xc0/0xf0
> [  138.522439] [c0000007d018be30] [c00000000191baec] system_call+0x38/0xfc
>
> Signed-off-by: Denis Kirjanov <kda at linux-powerpc.org>
> ---
>  arch/powerpc/kvm/book3s_hv.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
> index 1ec86d9..cb4ff36 100644
> --- a/arch/powerpc/kvm/book3s_hv.c
> +++ b/arch/powerpc/kvm/book3s_hv.c
> @@ -3930,7 +3930,7 @@ static int kvmppc_book3s_init_hv(void)
>  	 * indirectly, via OPAL.
>  	 */
>  #ifdef CONFIG_SMP
> -	if (!get_paca()->kvm_hstate.xics_phys) {
> +	if (!local_paca->kvm_hstate.xics_phys) {
>  		struct device_node *np;
>
>  		np = of_find_compatible_node(NULL, NULL, "ibm,opal-intc");
> --
> 1.8.3.1
>
>