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From:   "Jason A. Donenfeld" <Jason@zx2c4.com>
Date:   Thu, 26 May 2022 23:19:46 +0200
Message-ID: <CAHmME9pSZYZSz3YLRK7onO0E6zq9_B1GNwoTOkEQy_kws200Fw@mail.gmail.com>
Subject: Re: [PATCH] splice: allow direct splicing with chardevs
To:     viro@zeniv.linux.org.uk
Cc:     linux-kernel@vger.kernel.org, Jens Axboe <axboe@kernel.dk>
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Hey Al,

On 5/20/22, Jens Axboe <axboe@kernel.dk> wrote:
> On 5/20/22 3:57 AM, Jason A. Donenfeld wrote:
>> The original direct splicing mechanism from Jens required the input to
>> be a regular file because it was avoiding the special socket case. It
>> also recognized blkdevs as being close enough to a regular file. But it
>> forgot about chardevs, which behave the same way and work fine here.
>>
>> This commit adds the missing S_ISCHR condition so that chardevs such as
>> /dev/urandom can be directly spliced without strangely returning
>> -EINVAL.
>
> Should be fine to turn this on for char devices:
>
> Reviewed-by: Jens Axboe <axboe@kernel.dk>
>

Was wondering if this would make 5.19. That'd be nice, as it's the
release in which we switch to read_iter().

Jason