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From:   "Kassey Li (QUIC)" <quic_yingangl@quicinc.com>
To:     Andrew Morton <akpm@linux-foundation.org>,
        "Kassey Li (QUIC)" <quic_yingangl@quicinc.com>
CC:     "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Sasha Levin <sashal@kernel.org>,
        Joonsoo Kim <iamjoonsoo.kim@lge.com>,
        Minchan Kim <minchan@kernel.org>
Subject: RE: [PATCH] mm/cma_debug.c: align the name buffer length as struct
 cma
Thread-Topic: [PATCH] mm/cma_debug.c: align the name buffer length as struct
 cma
Thread-Index: AQHYm1AssKvX2GcRnUi/HpkM3uT0Da2GynYAgABJtKA=
Date:   Wed, 20 Jul 2022 10:45:33 +0000
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References: <20220719091554.27864-1-quic_yingangl@quicinc.com>
 <20220719161836.b0ad5cdfb0aec0c04a862122@linux-foundation.org>
In-Reply-To: <20220719161836.b0ad5cdfb0aec0c04a862122@linux-foundation.org>
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Hi, Andrew:=20

Is it the case that the output is never >16 chars anyway?  If so, we'll be =
OK.   =20
>> Yes.  I verified on my device by giving cma.name length l< 16 and >16 bo=
th. Result is OK.   I mean > 16 showed correctly with this patch.=20
>> without this patch, cma.name > 16, only showed 16 characters.=20

Best Regards
Kassey

This technical data may be subject to U.S. and international export, re-exp=
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-----Original Message-----
From: Andrew Morton <akpm@linux-foundation.org>=20
Sent: Wednesday, July 20, 2022 7:19 AM
To: Kassey Li (QUIC) <quic_yingangl@quicinc.com>
Cc: linux-kernel@vger.kernel.org; Sasha Levin <sashal@kernel.org>; Joonsoo =
Kim <iamjoonsoo.kim@lge.com>; Minchan Kim <minchan@kernel.org>
Subject: Re: [PATCH] mm/cma_debug.c: align the name buffer length as struct=
 cma

On Tue, 19 Jul 2022 17:15:54 +0800 Kassey Li <quic_yingangl@quicinc.com> wr=
ote:

> Signed-off-by: Kassey Li <quic_yingangl@quicinc.com>
> ---
>  mm/cma_debug.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>=20
> diff --git a/mm/cma_debug.c b/mm/cma_debug.c index=20
> 2e7704955f4f..c3ffe253e055 100644
> --- a/mm/cma_debug.c
> +++ b/mm/cma_debug.c
> @@ -163,7 +163,7 @@ DEFINE_DEBUGFS_ATTRIBUTE(cma_alloc_fops, NULL,=20
> cma_alloc_write, "%llu\n");  static void cma_debugfs_add_one(struct=20
> cma *cma, struct dentry *root_dentry)  {
>  	struct dentry *tmp;
> -	char name[16];
> +	char name[CMA_MAX_NAME];
> =20
>  	scnprintf(name, sizeof(name), "cma-%s", cma->name);

Seems logical.  But as CMA_MAX_NAME=3D64, this could result in alteration o=
f the output: less truncation of the original name.

Is it the case that the output is never >16 chars anyway?  If so, we'll be =
OK. =20