[PATCH -next] powerpc/powernv: add NULL check after kzalloc
Fixes coccicheck warning:
./arch/powerpc/platforms/powernv/opal.c:813:1-5:
alloc with no test, possible model on line 814
Add NULL check after kzalloc.
Signed-off-by: Chen Zhou
---
arch/powerpc/platforms/powernv/opal.c | 4
1 file changed, 4 insertions(+)
diff --git a/arch/powerpc/platforms/powernv/opal.c
b/arch/powerpc/platforms/powernv/opal.c
index 2b3dfd0b6cdd..d95954ad4c0a 100644
--- a/arch/powerpc/platforms/powernv/opal.c
+++ b/arch/powerpc/platforms/powernv/opal.c
@@ -811,6 +811,10 @@ static int opal_add_one_export(struct kobject *parent,
const char *export_name,
goto out;
attr = kzalloc(sizeof(*attr), GFP_KERNEL);
+ if (!attr) {
+ rc = -ENOMEM;
+ goto out;
+ }
name = kstrdup(export_name, GFP_KERNEL);
if (!name) {
rc = -ENOMEM;
--
2.20.1
[PATCH -next] KVM: PPC: Book3S HV: remove redundant NULL check
Free function kfree() already does NULL check, so the additional check is unnecessary, just remove it. Signed-off-by: Chen Zhou --- arch/powerpc/kvm/book3s_hv_nested.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/arch/powerpc/kvm/book3s_hv_nested.c b/arch/powerpc/kvm/book3s_hv_nested.c index dc97e5b..cad3243 100644 --- a/arch/powerpc/kvm/book3s_hv_nested.c +++ b/arch/powerpc/kvm/book3s_hv_nested.c @@ -1416,8 +1416,7 @@ static long int __kvmhv_nested_page_fault(struct kvm_run *run, rmapp = &memslot->arch.rmap[gfn - memslot->base_gfn]; ret = kvmppc_create_pte(kvm, gp->shadow_pgtable, pte, n_gpa, level, mmu_seq, gp->shadow_lpid, rmapp, &n_rmap); - if (n_rmap) - kfree(n_rmap); + kfree(n_rmap); if (ret == -EAGAIN) ret = RESUME_GUEST; /* Let the guest try again */ -- 2.7.4
[PATCH -next] PCI: rpaphp: remove set but not used variable 'value'
Fixes gcc '-Wunused-but-set-variable' warning:
drivers/pci/hotplug/rpaphp_core.c: In function is_php_type:
drivers/pci/hotplug/rpaphp_core.c:291:16: warning:
variable value set but not used [-Wunused-but-set-variable]
Reported-by: Hulk Robot
Signed-off-by: Chen Zhou
---
drivers/pci/hotplug/rpaphp_core.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/drivers/pci/hotplug/rpaphp_core.c
b/drivers/pci/hotplug/rpaphp_core.c
index e408e40..5d871ef 100644
--- a/drivers/pci/hotplug/rpaphp_core.c
+++ b/drivers/pci/hotplug/rpaphp_core.c
@@ -288,11 +288,10 @@ EXPORT_SYMBOL_GPL(rpaphp_check_drc_props);
static int is_php_type(char *drc_type)
{
- unsigned long value;
char *endptr;
/* PCI Hotplug nodes have an integer for drc_type */
- value = simple_strtoul(drc_type, &endptr, 10);
+ simple_strtoul(drc_type, &endptr, 10);
if (endptr == drc_type)
return 0;
--
2.7.4
[PATCH -next] powerpc/maple: fix comparing pointer to 0
Fixes coccicheck warning:
./arch/powerpc/platforms/maple/setup.c:232:15-16:
WARNING comparing pointer to 0
Compare pointer-typed values to NULL rather than 0.
Signed-off-by: Chen Zhou
---
arch/powerpc/platforms/maple/setup.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/powerpc/platforms/maple/setup.c
b/arch/powerpc/platforms/maple/setup.c
index 47f7310..00a0780 100644
--- a/arch/powerpc/platforms/maple/setup.c
+++ b/arch/powerpc/platforms/maple/setup.c
@@ -229,7 +229,7 @@ static void __init maple_init_IRQ(void)
root = of_find_node_by_path("/");
naddr = of_n_addr_cells(root);
opprop = of_get_property(root, "platform-open-pic", &opplen);
- if (opprop != 0) {
+ if (opprop) {
openpic_addr = of_read_number(opprop, naddr);
has_isus = (opplen > naddr);
printk(KERN_DEBUG "OpenPIC addr: %lx, has ISUs: %d\n",
--
2.7.4
[PATCH V2] powerpc/setup_64: use DEFINE_DEBUGFS_ATTRIBUTE to define fops_rfi_flush
Use DEFINE_DEBUGFS_ATTRIBUTE rather than DEFINE_SIMPLE_ATTRIBUTE for
debugfs files.
In order to protect against file removal races, debugfs files created via
debugfs_create_file() are wrapped by a struct file_operations at their
opening.
If the original struct file_operations is known to be safe against removal
races already, the proxy creation may be bypassed by creating the files
using DEFINE_DEBUGFS_ATTRIBUTE() and debugfs_create_file_unsafe().
Signed-off-by: Chen Zhou
---
Changes since v1:
- modify commit message.
arch/powerpc/kernel/setup_64.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c
index 6104917..4b9fbb2 100644
--- a/arch/powerpc/kernel/setup_64.c
+++ b/arch/powerpc/kernel/setup_64.c
@@ -956,11 +956,11 @@ static int rfi_flush_get(void *data, u64 *val)
return 0;
}
-DEFINE_SIMPLE_ATTRIBUTE(fops_rfi_flush, rfi_flush_get, rfi_flush_set,
"%llu\n");
+DEFINE_DEBUGFS_ATTRIBUTE(fops_rfi_flush, rfi_flush_get, rfi_flush_set,
"%llu\n");
static __init int rfi_flush_debugfs_init(void)
{
- debugfs_create_file("rfi_flush", 0600, powerpc_debugfs_root, NULL,
&fops_rfi_flush);
+ debugfs_create_file_unsafe("rfi_flush", 0600, powerpc_debugfs_root,
NULL, &fops_rfi_flush);
return 0;
}
device_initcall(rfi_flush_debugfs_init);
--
2.7.4
Re: [PATCH] powerpc/setup_64: use DEFINE_DEBUGFS_ATTRIBUTE to define fops_rfi_flush
Hi Michael,
On 2019/12/18 19:02, Michael Ellerman wrote:
> Chen Zhou writes:
>> Use DEFINE_DEBUGFS_ATTRIBUTE rather than DEFINE_SIMPLE_ATTRIBUTE for
>> debugfs files.
>>
>> Semantic patch information:
>> Rationale: DEFINE_SIMPLE_ATTRIBUTE + debugfs_create_file()
>> imposes some significant overhead as compared to
>> DEFINE_DEBUGFS_ATTRIBUTE + debugfs_create_file_unsafe().
>
> I know you didn't write this text, but these change logs are not great.
> It doesn't really explain why you're doing it. And it is alarming that
> you're converting *to* a function with "unsafe" in the name.
>
> The commit that added the script:
>
> 5103068eaca2 ("debugfs, coccinelle: check for obsolete
> DEFINE_SIMPLE_ATTRIBUTE() usage")
>
> Has a bit more explanation.
>
> Maybe something like this:
>
> In order to protect against file removal races, debugfs files created via
> debugfs_create_file() are wrapped by a struct file_operations at their
> opening.
>
> If the original struct file_operations is known to be safe against removal
> races already, the proxy creation may be bypassed by creating the files
> using DEFINE_DEBUGFS_ATTRIBUTE() and debugfs_create_file_unsafe().
>
>
> The part that's not explained is why this file is "known to be safe
> against removal races already"?
>
> It also seems this conversion will make the file no longer seekable,
> because DEFINE_SIMPLE_ATTRIBUTE() uses generic_file_llseek() whereas
> DEFINE_DEBUGFS_ATTRIBUTE() uses no_llseek.
>
> That is probably fine, but should be mentioned.
Thanks for your explanation. This part indeed should be mentioned.
Chen Zhou
>
> cheers
>
>> Signed-off-by: Chen Zhou
>> ---
>> arch/powerpc/kernel/setup_64.c | 4 ++--
>> 1 file changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c
>> index 6104917..4b9fbb2 100644
>> --- a/arch/powerpc/kernel/setup_64.c
>> +++ b/arch/powerpc/kernel/setup_64.c
>> @@ -956,11 +956,11 @@ static int rfi_flush_get(void *data, u64 *val)
>> return 0;
>> }
>>
>> -DEFINE_SIMPLE_ATTRIBUTE(fops_rfi_flush, rfi_flush_get, rfi_flush_set,
>> "%llu\n");
>> +DEFINE_DEBUGFS_ATTRIBUTE(fops_rfi_flush, rfi_flush_get, rfi_flush_set,
>> "%llu\n");
>>
>> static __init int rfi_flush_debugfs_init(void)
>> {
>> -debugfs_create_file("rfi_flush", 0600, powerpc_debugfs_root, NULL,
>> &fops_rfi_flush);
>> +debugfs_create_file_unsafe("rfi_flush", 0600, powerpc_debugfs_root,
>> NULL, &fops_rfi_flush);
>> return 0;
>> }
>> device_initcall(rfi_flush_debugfs_init);
>> --
>> 2.7.4
>
> .
>
[PATCH] powerpc/setup_64: use DEFINE_DEBUGFS_ATTRIBUTE to define fops_rfi_flush
Use DEFINE_DEBUGFS_ATTRIBUTE rather than DEFINE_SIMPLE_ATTRIBUTE for
debugfs files.
Semantic patch information:
Rationale: DEFINE_SIMPLE_ATTRIBUTE + debugfs_create_file()
imposes some significant overhead as compared to
DEFINE_DEBUGFS_ATTRIBUTE + debugfs_create_file_unsafe().
Signed-off-by: Chen Zhou
---
arch/powerpc/kernel/setup_64.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c
index 6104917..4b9fbb2 100644
--- a/arch/powerpc/kernel/setup_64.c
+++ b/arch/powerpc/kernel/setup_64.c
@@ -956,11 +956,11 @@ static int rfi_flush_get(void *data, u64 *val)
return 0;
}
-DEFINE_SIMPLE_ATTRIBUTE(fops_rfi_flush, rfi_flush_get, rfi_flush_set,
"%llu\n");
+DEFINE_DEBUGFS_ATTRIBUTE(fops_rfi_flush, rfi_flush_get, rfi_flush_set,
"%llu\n");
static __init int rfi_flush_debugfs_init(void)
{
- debugfs_create_file("rfi_flush", 0600, powerpc_debugfs_root, NULL,
&fops_rfi_flush);
+ debugfs_create_file_unsafe("rfi_flush", 0600, powerpc_debugfs_root,
NULL, &fops_rfi_flush);
return 0;
}
device_initcall(rfi_flush_debugfs_init);
--
2.7.4
