[2/2] KVM: x86: Fix a typo about the usage of kvcalloc()

  Swap the 1st and 2nd arguments to be consistent with the usage of
kvcalloc().

Fixes: c9b8fecddb5b ("KVM: use kvcalloc for array allocations")
Signed-off-by: Liao Chang <liaochang1@huawei.com>
---
 arch/x86/kvm/cpuid.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
  

On Thu, Nov 03, 2022 at 09:17:49AM +0800, Liao Chang wrote:
> Swap the 1st and 2nd arguments to be consistent with the usage of
> kvcalloc().
> 

This isn't typofix as suggested from the patch subject, right?
  

On Thu, 2022-11-03 at 12:18 +0800, liaochang (A) wrote:
> 
> 在 2022/11/3 10:37, Bagas Sanjaya 写道:
> > This isn't typofix as suggested from the patch subject, right?
> 
> Well, since kvcalloc uses the product of 1st and 2nd argument to do allocation,
> hence current code supposes to work well, but the usage is obviously no sense,
> that is why i name it a 'typo' and make it correct ;)
> 

Seems there are several of these typo/defects.

$ git grep -P 'calloc\s*\(\s*sizeof'
arch/x86/kvm/cpuid.c:   array.entries = kvcalloc(sizeof(struct kvm_cpuid_entry2), cpuid->nent, GFP_KERNEL);
drivers/gpu/drm/nouveau/nouveau_svm.c:  buffer->fault = kvcalloc(sizeof(*buffer->fault), buffer->entries, GFP_KERNEL);
drivers/scsi/bfa/bfad_bsg.c:    buf_base = kcalloc(sizeof(struct bfad_buf_info) +
drivers/soc/fsl/dpio/dpio-service.c:    ed = kcalloc(sizeof(struct qbman_eq_desc), 32, GFP_KERNEL);
fs/btrfs/send.c:        sctx->clone_roots = kvcalloc(sizeof(*sctx->clone_roots),
kernel/bpf/bpf_local_storage.c: smap->buckets = kvcalloc(sizeof(*smap->buckets), nbuckets,
kernel/watch_queue.c:   pages = kcalloc(sizeof(struct page *), nr_pages, GFP_KERNEL);
tools/lib/bpf/libbpf.c: gen = calloc(sizeof(*gen), 1);
tools/objtool/check.c:  struct cfi_state *cfi = calloc(sizeof(struct cfi_state), 1);
tools/objtool/check.c:  file->pv_ops = calloc(sizeof(struct pv_state), nr);
tools/perf/builtin-record.c:            rec->switch_output.filenames = calloc(sizeof(char *),
tools/perf/util/bpf-loader.c:   priv = calloc(sizeof(*priv), 1);
tools/perf/util/hist.c:         he->res_samples = calloc(sizeof(struct res_sample),
tools/perf/util/metricgroup.c:  metric_events = calloc(sizeof(void *), ids_size + 1);
tools/perf/util/stat-shadow.c:                  metric_events = calloc(sizeof(struct evsel *),
tools/perf/util/synthetic-events.c:     synthesize_threads = calloc(sizeof(pthread_t), thread_nr);
tools/perf/util/synthetic-events.c:     args = calloc(sizeof(*args), thread_nr);
tools/testing/selftests/arm64/fp/fp-stress.c:   children = calloc(sizeof(*children), tests);
tools/testing/selftests/bpf/prog_tests/fexit_bpf2bpf.c: link = calloc(sizeof(struct bpf_link *), prog_cnt);
tools/testing/selftests/bpf/prog_tests/fexit_bpf2bpf.c: prog = calloc(sizeof(struct bpf_program *), prog_cnt);
tools/testing/selftests/bpf/test_progs.c:       dispatcher_threads = calloc(sizeof(pthread_t), env.workers);
tools/testing/selftests/bpf/test_progs.c:       data = calloc(sizeof(struct dispatch_data), env.workers);
tools/testing/selftests/bpf/test_progs.c:       env.worker_current_test = calloc(sizeof(int), env.workers);
tools/testing/selftests/bpf/test_progs.c:               env.worker_pids = calloc(sizeof(__pid_t), env.workers);
tools/testing/selftests/bpf/test_progs.c:               env.worker_socks = calloc(sizeof(int), env.workers);
tools/testing/selftests/memfd/fuse_test.c:      zero = calloc(sizeof(*zero), mfd_def_size);
  

On 11/3/22 02:17, Liao Chang wrote:
> Swap the 1st and 2nd arguments to be consistent with the usage of
> kvcalloc().
> 
> Fixes: c9b8fecddb5b ("KVM: use kvcalloc for array allocations")
> Signed-off-by: Liao Chang<liaochang1@huawei.com>
> ---
>   arch/x86/kvm/cpuid.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
> index 7065462378e2..b33c18b142c2 100644
> --- a/arch/x86/kvm/cpuid.c
> +++ b/arch/x86/kvm/cpuid.c
> @@ -1331,7 +1331,7 @@ int kvm_dev_ioctl_get_cpuid(struct kvm_cpuid2 *cpuid,
>   	if (sanity_check_entries(entries, cpuid->nent, type))
>   		return -EINVAL;
>   
> -	array.entries = kvcalloc(sizeof(struct kvm_cpuid_entry2), cpuid->nent, GFP_KERNEL);
> +	array.entries = kvcalloc(cpuid->nent, sizeof(struct kvm_cpuid_entry2), GFP_KERNEL);
>   	if (!array.entries)
>   		return -ENOMEM;
>   

It doesn't make any difference, but scripts/checkpatch.pl checks it so
let's fix the sole occurrence in KVM.

However, please send a patch to scripts/checkpatch.pl to include calloc(),
kvmalloc_array and kvcalloc() in the matched functions:

# check for alloc argument mismatch
                 if ($line =~ /\b((?:devm_)?(?:kcalloc|kmalloc_array))\s*\(\s*sizeof\b/) {
                         WARN("ALLOC_ARRAY_ARGS",
                              "$1 uses number as first arg, sizeof is generally wrong\n" . $herecurr);
                 }


Paolo
  

在 2022/11/3 21:39, Paolo Bonzini 写道:
> On 11/3/22 02:17, Liao Chang wrote:
>> Swap the 1st and 2nd arguments to be consistent with the usage of
>> kvcalloc().
>>
>> Fixes: c9b8fecddb5b ("KVM: use kvcalloc for array allocations")
>> Signed-off-by: Liao Chang<liaochang1@huawei.com>
>> ---
>>   arch/x86/kvm/cpuid.c | 2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
>> index 7065462378e2..b33c18b142c2 100644
>> --- a/arch/x86/kvm/cpuid.c
>> +++ b/arch/x86/kvm/cpuid.c
>> @@ -1331,7 +1331,7 @@ int kvm_dev_ioctl_get_cpuid(struct kvm_cpuid2 *cpuid,
>>       if (sanity_check_entries(entries, cpuid->nent, type))
>>           return -EINVAL;
>>   -    array.entries = kvcalloc(sizeof(struct kvm_cpuid_entry2), cpuid->nent, GFP_KERNEL);
>> +    array.entries = kvcalloc(cpuid->nent, sizeof(struct kvm_cpuid_entry2), GFP_KERNEL);
>>       if (!array.entries)
>>           return -ENOMEM;
>>   
> 
> It doesn't make any difference, but scripts/checkpatch.pl checks it so
> let's fix the sole occurrence in KVM.
> 
> However, please send a patch to scripts/checkpatch.pl to include calloc(),
> kvmalloc_array and kvcalloc() in the matched functions:
> 
> # check for alloc argument mismatch
>                 if ($line =~ /\b((?:devm_)?(?:kcalloc|kmalloc_array))\s*\(\s*sizeof\b/) {
>                         WARN("ALLOC_ARRAY_ARGS",
>                              "$1 uses number as first arg, sizeof is generally wrong\n" . $herecurr);
>                 }

I ready send a patch to enhance the checking for array allocator family,
please check out patch "checkpatch: Add check for array allocator family argument order".

Thanks.

> 
> 
> Paolo
> 
> 
> .