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Message-ID: <e7a6add0-5526-4efd-8b00-07e399e292c1@kylinos.cn>
Date: Mon, 22 Jan 2024 15:47:01 +0800
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Subject: Re: [PATCH v3] x86/xen: Add some null pointer checking to smp.c
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To: Markus Elfring <Markus.Elfring@web.de>, xen-devel@lists.xenproject.org,
 kernel-janitors@vger.kernel.org, Boris Ostrovsky
 <boris.ostrovsky@oracle.com>, Borislav Petkov <bp@alien8.de>,
 Dave Hansen <dave.hansen@linux.intel.com>, "H. Peter Anvin" <hpa@zytor.com>,
 Ingo Molnar <mingo@redhat.com>, =?UTF-8?B?SsO8cmdlbiBHcm/Dnw==?=
 <jgross@suse.com>, Thomas Gleixner <tglx@linutronix.de>, x86@kernel.org
Cc: kernel test robot <lkp@intel.com>, LKML <linux-kernel@vger.kernel.org>
References: <20240119094948.275390-1-chentao@kylinos.cn>
 <91af4a8c-d2e2-416f-b02e-5d69553c5998@web.de>
From: Kunwu Chan <chentao@kylinos.cn>
In-Reply-To: <91af4a8c-d2e2-416f-b02e-5d69553c5998@web.de>
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On 2024/1/19 18:40, Markus Elfring wrote:
>> kasprintf() returns a pointer to dynamically allocated memory
>> which can be NULL upon failure. Ensure the allocation was successful
>> by checking the pointer validity.
> =E2=80=A6
>> ---
>> Changes in v3:
>>      - Remove rc initialization
>>      - Simply error paths by adding a new label 'fail_mem'
> =E2=80=A6
>=20
> I became curious if you would like to simplify further source code plac=
es.
This function hasn't changed in years, so it's OK for now.
>=20
>=20
>> +++ b/arch/x86/xen/smp.c
>> @@ -65,6 +65,8 @@ int xen_smp_intr_init(unsigned int cpu)
>>   	char *resched_name, *callfunc_name, *debug_name;
>>
>>   	resched_name =3D kasprintf(GFP_KERNEL, "resched%d", cpu);
>> +	if (!resched_name)
>> +		goto fail_mem;
>=20
> Would you like to add a blank line after such a statement?
Sure, I could do it in next patch.
>=20
>=20
>>   	per_cpu(xen_resched_irq, cpu).name =3D resched_name;
> =E2=80=A6
>=20
> Please compare with your subsequent suggestion.
I=E2=80=99ve seend a reply.
>=20
> =E2=80=A6
>> @@ -101,6 +108,9 @@ int xen_smp_intr_init(unsigned int cpu)
>>   	}
>>
>>   	callfunc_name =3D kasprintf(GFP_KERNEL, "callfuncsingle%d", cpu);
>> +	if (!callfunc_name)
>> +		goto fail_mem;
>> +
>>   	per_cpu(xen_callfuncsingle_irq, cpu).name =3D callfunc_name;
> =E2=80=A6
>=20
> Regards,
> Markus
--=20
Thanks,
   Kunwu