From: Kefeng Wang wangkefeng.wang@huawei.com
[ Upstream commit 80709af7325d179b433817f421c85449f2454046 ]
Use raw_smp_processor_id instead of smp_processor_id() to fix warning,
BUG: using smp_processor_id() in preemptible [00000000] code: init/1 caller is debug_smp_processor_id+0x1c/0x26 CPU: 0 PID: 1 Comm: init Not tainted 5.10.0-rc4 #211 Call Trace: walk_stackframe+0x0/0xaa show_stack+0x32/0x3e dump_stack+0x76/0x90 check_preemption_disabled+0xaa/0xac debug_smp_processor_id+0x1c/0x26 get_cache_size+0x18/0x68 load_elf_binary+0x868/0xece bprm_execve+0x224/0x498 kernel_execve+0xdc/0x142 run_init_process+0x90/0x9e try_to_run_init_process+0x12/0x3c kernel_init+0xb4/0xf8 ret_from_exception+0x0/0xc
The issue is found when CONFIG_DEBUG_PREEMPT enabled.
Reviewed-by: Atish Patra atish.patra@wdc.com Tested-by: Atish Patra atish.patra@wdc.com Signed-off-by: Kefeng Wang wangkefeng.wang@huawei.com [Palmer: Added a comment.] Signed-off-by: Palmer Dabbelt palmerdabbelt@google.com Signed-off-by: Sasha Levin sashal@kernel.org --- arch/riscv/kernel/cacheinfo.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-)
diff --git a/arch/riscv/kernel/cacheinfo.c b/arch/riscv/kernel/cacheinfo.c index de59dd457b415..d867813570442 100644 --- a/arch/riscv/kernel/cacheinfo.c +++ b/arch/riscv/kernel/cacheinfo.c @@ -26,7 +26,16 @@ cache_get_priv_group(struct cacheinfo *this_leaf)
static struct cacheinfo *get_cacheinfo(u32 level, enum cache_type type) { - struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(smp_processor_id()); + /* + * Using raw_smp_processor_id() elides a preemptability check, but this + * is really indicative of a larger problem: the cacheinfo UABI assumes + * that cores have a homonogenous view of the cache hierarchy. That + * happens to be the case for the current set of RISC-V systems, but + * likely won't be true in general. Since there's no way to provide + * correct information for these systems via the current UABI we're + * just eliding the check for now. + */ + struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(raw_smp_processor_id()); struct cacheinfo *this_leaf; int index;