qemu-devel.nongnu.org archive mirror
 help / color / mirror / Atom feed
From: Richard Henderson <richard.henderson@linaro.org>
To: Carlos Santos <casantos@redhat.com>,
	Peter Maydell <peter.maydell@linaro.org>
Cc: QEMU Developers <qemu-devel@nongnu.org>
Subject: Re: [PATCH] util/cacheinfo: fix crash when compiling with uClibc
Date: Thu, 16 Jan 2020 14:04:35 -1000	[thread overview]
Message-ID: <48f341e2-5844-2929-1c38-4ecd26ed8546@linaro.org> (raw)
In-Reply-To: <CAC1VKkPfacdLkXfHVNm-josjtds3Xsj=9NhRfNaQTyRv4XxEfQ@mail.gmail.com>

On 12/16/19 1:18 AM, Carlos Santos wrote:
> On Thu, Oct 17, 2019 at 8:06 PM Carlos Santos <casantos@redhat.com> wrote:
>>
>> On Thu, Oct 17, 2019 at 9:47 AM Peter Maydell <peter.maydell@linaro.org> wrote:
>>>
>>> On Thu, 17 Oct 2019 at 13:39, <casantos@redhat.com> wrote:
>>>>
>>>> From: Carlos Santos <casantos@redhat.com>
>>>>
>>>> uClibc defines _SC_LEVEL1_ICACHE_LINESIZE and _SC_LEVEL1_DCACHE_LINESIZE
>>>> but the corresponding sysconf calls returns -1, which is a valid result,
>>>> meaning that the limit is indeterminate.
>>>>
>>>> Handle this situation using the fallback values instead of crashing due
>>>> to an assertion failure.
>>>>
>>>> Signed-off-by: Carlos Santos <casantos@redhat.com>
>>>> ---
>>>>  util/cacheinfo.c | 10 ++++++++--
>>>>  1 file changed, 8 insertions(+), 2 deletions(-)
>>>>
>>>> diff --git a/util/cacheinfo.c b/util/cacheinfo.c
>>>> index ea6f3e99bf..d94dc6adc8 100644
>>>> --- a/util/cacheinfo.c
>>>> +++ b/util/cacheinfo.c
>>>> @@ -93,10 +93,16 @@ static void sys_cache_info(int *isize, int *dsize)
>>>>  static void sys_cache_info(int *isize, int *dsize)
>>>>  {
>>>>  # ifdef _SC_LEVEL1_ICACHE_LINESIZE
>>>> -    *isize = sysconf(_SC_LEVEL1_ICACHE_LINESIZE);
>>>> +    int tmp_isize = (int) sysconf(_SC_LEVEL1_ICACHE_LINESIZE);
>>>
>>> Do we need the cast here ?
>>
>> It's there to remind the reader that a type coercion may occur, since
>> sysconf() returns a long and isize is an int.
>>
>>>> +    if (tmp_isize > 0) {
>>>> +        *isize = tmp_isize;
>>>> +    }
>>>>  # endif
>>>>  # ifdef _SC_LEVEL1_DCACHE_LINESIZE
>>>> -    *dsize = sysconf(_SC_LEVEL1_DCACHE_LINESIZE);
>>>> +    int tmp_dsize = (int) sysconf(_SC_LEVEL1_DCACHE_LINESIZE);
>>>> +    if (tmp_dsize > 0) {
>>>> +        *dsize = tmp_dsize;
>>>> +    }
>>>>  # endif
>>>>  }
>>>>  #endif /* sys_cache_info */
>>>> --
>>>
>>> thanks
>>> -- PMM
>>
>> --
>> Carlos Santos
>> Senior Software Maintenance Engineer
>> Red Hat
>> casantos@redhat.com    T: +55-11-3534-6186
> 
> Hi,
> 
> Any chance to have this merged for Christmas? :-)

No, but it's queued now.  ;-)


r~



  reply	other threads:[~2020-01-17  0:05 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-10-17 12:37 [PATCH] util/cacheinfo: fix crash when compiling with uClibc casantos
2019-10-17 12:47 ` Peter Maydell
2019-10-17 23:06   ` Carlos Santos
2019-12-16 11:18     ` Carlos Santos
2020-01-17  0:04       ` Richard Henderson [this message]
2020-01-20 18:26         ` Carlos Santos

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=48f341e2-5844-2929-1c38-4ecd26ed8546@linaro.org \
    --to=richard.henderson@linaro.org \
    --cc=casantos@redhat.com \
    --cc=peter.maydell@linaro.org \
    --cc=qemu-devel@nongnu.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).