linux-kernel - Re: [PATCH v3 21/21] sparc64: use match

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Thu, 21 Jun 2018 09:13:00 +0800
From:   Yisheng Xie <xieyisheng1@...wei.com>
To:     Andy Shevchenko <andy.shevchenko@...il.com>
CC:     Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        "David S. Miller" <davem@...emloft.net>,
        Anthony Yznaga <anthony.yznaga@...cle.com>,
        Pavel Tatashin <pasha.tatashin@...cle.com>,
        <sparclinux@...r.kernel.org>,
        Kefeng Wang <wangkefeng.wang@...wei.com>
Subject: Re: [PATCH v3 21/21] sparc64: use match_string() helper

Hi Andy,

Sorry for late response. I will take your suggestion in next version.

Thanks
Yisheng

On 2018/6/6 13:01, Andy Shevchenko wrote:
> On Wed, Jun 6, 2018 at 5:19 AM, Yisheng Xie <xieyisheng1@...wei.com> wrote:
>> match_string() returns the index of an array for a matching string,
>> which can be used instead of open coded variant.
>>
> 
> Thanks for an update.
> My comments below.
> 
> I think you need to mentioned the string literal change in the commit message.
> 
>> Cc: "David S. Miller" <davem@...emloft.net>
>> Cc: Anthony Yznaga <anthony.yznaga@...cle.com>
>> Cc: Pavel Tatashin <pasha.tatashin@...cle.com>
>> Cc: sparclinux@...r.kernel.org
>> Signed-off-by: Yisheng Xie <xieyisheng1@...wei.com>
>> ---
>> v3:
>>  - add string literal instead of NULL for array hwcaps to make it
>>    can use match_string() too.  - per Andy
>> v2
>>  - new add for use match_string() helper patchset.
>>
>>  arch/sparc/kernel/setup_64.c | 23 +++++++++--------------
>>  1 file changed, 9 insertions(+), 14 deletions(-)
>>
>> diff --git a/arch/sparc/kernel/setup_64.c b/arch/sparc/kernel/setup_64.c
>> index 7944b3c..4f0ec0c 100644
>> --- a/arch/sparc/kernel/setup_64.c
>> +++ b/arch/sparc/kernel/setup_64.c
>> @@ -401,7 +401,7 @@ void __init start_early_boot(void)
>>          */
>>         "mul32", "div32", "fsmuld", "v8plus", "popc", "vis", "vis2",
>>         "ASIBlkInit", "fmaf", "vis3", "hpc", "random", "trans", "fjfmau",
>> -       "ima", "cspare", "pause", "cbcond", NULL /*reserved for crypto */,
>> +       "ima", "cspare", "pause", "cbcond", "resv" /*reserved for crypto */,
>>         "adp",
> 
> Why not to spell "crypto" explicitly and remove comment?
> 
>>  };
>>
>> @@ -418,7 +418,7 @@ void cpucap_info(struct seq_file *m)
>>         seq_puts(m, "cpucaps\t\t: ");
>>         for (i = 0; i < ARRAY_SIZE(hwcaps); i++) {
>>                 unsigned long bit = 1UL << i;
>> -               if (hwcaps[i] && (caps & bit)) {
>> +               if (bit != HWCAP_SPARC_CRYPTO && (caps & bit)) {
> 
> I would rather swap the order of subsonditions to check if caps has a
> bit first, and then exclude CRYPTO.
> 
>>                         seq_printf(m, "%s%s",
>>                                    printed ? "," : "", hwcaps[i]);
>>                         printed++;
>> @@ -472,7 +472,7 @@ static void __init report_hwcaps(unsigned long caps)
>>
>>         for (i = 0; i < ARRAY_SIZE(hwcaps); i++) {
>>                 unsigned long bit = 1UL << i;
>> -               if (hwcaps[i] && (caps & bit))
>> +               if (bit != HWCAP_SPARC_CRYPTO && (caps & bit))
>>                         report_one_hwcap(&printed, hwcaps[i]);
> 
> Ditto.
> 
>>         }
>>         if (caps & HWCAP_SPARC_CRYPTO)
>> @@ -504,18 +504,13 @@ static unsigned long __init mdesc_cpu_hwcap_list(void)
>>         while (len) {
>>                 int i, plen;
>>
>> -               for (i = 0; i < ARRAY_SIZE(hwcaps); i++) {
>> -                       unsigned long bit = 1UL << i;
>> +               i = match_string(hwcaps, ARRAY_SIZE(hwcaps), prop);
>> +               if (i >= 0)
>> +                       caps |= (1UL << i);
> 
> Parens are redundant (and actually didn't present in the original code above).
> 
>>
>> -                       if (hwcaps[i] && !strcmp(prop, hwcaps[i])) {
>> -                               caps |= bit;
>> -                               break;
>> -                       }
>> -               }
>> -               for (i = 0; i < ARRAY_SIZE(crypto_hwcaps); i++) {
>> -                       if (!strcmp(prop, crypto_hwcaps[i]))
>> -                               caps |= HWCAP_SPARC_CRYPTO;
>> -               }
>> +               i = match_string(crypto_hwcaps, ARRAY_SIZE(crypto_hwcaps), prop);
>> +               if (i >= 0)
>> +                       caps |= HWCAP_SPARC_CRYPTO;
>>
>>                 plen = strlen(prop) + 1;
>>                 prop += plen;
>> --
>> 1.7.12.4
>>
>>
>>
> 
> 
>