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From:   Kees Cook <keescook@chromium.org>
Date:   Thu, 18 Oct 2018 11:01:38 -0700
Message-ID: <CAGXu5jL0eh3SQz5PEJTtSjgjkEoVYLZEfCjrpg-J3jF7edjDqA@mail.gmail.com>
Subject: Re: [PATCH] pstore: Refactor compression initialization
To:     Joe Perches <joe@perches.com>
Cc:     Joel Fernandes <joel@joelfernandes.org>,
        Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>,
        LKML <linux-kernel@vger.kernel.org>
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On Thu, Oct 18, 2018 at 10:14 AM, Joe Perches <joe@perches.com> wrote:
> On Wed, 2018-10-17 at 14:41 -0700, Kees Cook wrote:
>> With compression initialization now separated from pstore_register(),
>> there is no longer a good reason to do compression method selection
>> during fs init. Instead, merge everything together into the late init.
>> Additionally cleans up the reporting to be more clear.
> []
>> diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c
> []
>> @@ -274,36 +274,56 @@ static int pstore_decompress(void *in, void *out,
> []
>> -     big_oops_buf = kmalloc(big_oops_buf_sz, GFP_KERNEL);
>> -     if (!big_oops_buf) {
>> -             pr_err("allocate compression buffer error!\n");
>> +     buf = kmalloc(size, GFP_KERNEL);
>> +     if (!buf) {
>> +             pr_err("Failed %d byte compression buffer allocation for: %s\n",
>> +                    size, zbackend->name);
>
> Given that there is a generic OOM message emitted on
> kmalloc failures, rather than expanding the unnecessary
> alloc failure message, how about just deleting it instead?

I prefer including more context (i.e. the desired compression method).

-Kees

-- 
Kees Cook
Pixel Security