From: Sachin Kamat <sachin.kamat@linaro.org>
To: Greg KH <gregkh@linuxfoundation.org>
Cc: linux-kernel@vger.kernel.org, patches@linaro.org
Subject: Re: [PATCH 1/1] tty: vt: Remove redundant null check before kfree.
Date: Wed, 21 Nov 2012 20:59:08 +0530 [thread overview]
Message-ID: <CAK9yfHw=AjCQ+1VsXLZa=wtNopoZxSsd3xSa+_UDNYOOohY2dg@mail.gmail.com> (raw)
In-Reply-To: <20121121151604.GA21983@kroah.com>
On 21 November 2012 20:46, Greg KH <gregkh@linuxfoundation.org> wrote:
> On Wed, Nov 21, 2012 at 08:21:40PM +0530, Sachin Kamat wrote:
>> On 21 November 2012 20:16, Greg KH <gregkh@linuxfoundation.org> wrote:
>> > On Wed, Nov 21, 2012 at 10:49:07AM +0530, Sachin Kamat wrote:
>> >> kfree on a NULL pointer is a no-op.
>> >>
>> >> Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
>> >> ---
>> >> drivers/tty/vt/consolemap.c | 6 ++----
>> >> 1 files changed, 2 insertions(+), 4 deletions(-)
>> >>
>> >> diff --git a/drivers/tty/vt/consolemap.c b/drivers/tty/vt/consolemap.c
>> >> index 2aaa0c2..248381b 100644
>> >> --- a/drivers/tty/vt/consolemap.c
>> >> +++ b/drivers/tty/vt/consolemap.c
>> >> @@ -410,10 +410,8 @@ static void con_release_unimap(struct uni_pagedir *p)
>> >> kfree(p->inverse_translations[i]);
>> >> p->inverse_translations[i] = NULL;
>> >> }
>> >> - if (p->inverse_trans_unicode) {
>> >> - kfree(p->inverse_trans_unicode);
>> >> - p->inverse_trans_unicode = NULL;
>> >> - }
>> >> + kfree(p->inverse_trans_unicode);
>> >> + p->inverse_trans_unicode = NULL;
>> >
>> > kfree with NULL is a no-op, but the line after that just caused a kernel
>> > crash if it was NULL, so I can't accept this type of thing.
>> >
>> > Please be more careful.
>>
>> My mistake. Apologies for the same.
>>
>> Do we need to assign the pointer to NULL after freeing?
>
> It depends if it is checked later on, is it?
I will re-send this patch after deleting the assignment?
>
>> > What's with the patches@linaro.org email address? What is that for?
>> That is a logging mechanism (done by patchwork) for all patches sent
>> by Linaro engineers.
>
> So you can track it internally? Why?
Yes. For tracking the status.
>
> greg k-h
--
With warm regards,
Sachin
next prev parent reply other threads:[~2012-11-21 15:29 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-11-21 5:19 [PATCH 1/1] tty: vt: Remove redundant null check before kfree Sachin Kamat
2012-11-21 14:46 ` Greg KH
2012-11-21 14:51 ` Sachin Kamat
2012-11-21 15:16 ` Greg KH
2012-11-21 15:29 ` Sachin Kamat [this message]
2012-11-21 16:54 ` Greg KH
2012-11-21 22:43 ` Jiri Slaby
2012-11-21 23:00 ` Greg KH
2012-11-21 23:17 ` Jiri Slaby
2012-11-22 0:38 ` Greg KH
2012-11-22 5:19 ` Sachin Kamat
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to='CAK9yfHw=AjCQ+1VsXLZa=wtNopoZxSsd3xSa+_UDNYOOohY2dg@mail.gmail.com' \
--to=sachin.kamat@linaro.org \
--cc=gregkh@linuxfoundation.org \
--cc=linux-kernel@vger.kernel.org \
--cc=patches@linaro.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).