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Subject: Re: [PATCH] staging: r8188eu: Fix while-loop that iterates only once
To: David Laight <David.Laight@ACULAB.COM>,
 Larry Finger <Larry.Finger@lwfinger.net>,
 Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
 "linux-staging@lists.linux.dev" <linux-staging@lists.linux.dev>
Cc: "kernel-janitors@vger.kernel.org" <kernel-janitors@vger.kernel.org>,
 "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
References: <20210629163624.41543-1-colin.king@canonical.com>
 <ff4444d1d2204539945ded9bf06c94e6@AcuMS.aculab.com>
From: Colin Ian King <colin.king@canonical.com>
Message-ID: <b989a309-b706-2197-f0f7-51e838f4fcdf@canonical.com>
Date: Wed, 30 Jun 2021 07:44:47 +0100
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On 29/06/2021 22:53, David Laight wrote:
> From: Colin King
>> Sent: 29 June 2021 17:36
>>
>> The while-loop only iterates once becase the post increment test of count
>> being non-zero is false on the first iteration because count is zero. Fix
>> this by incrementing count using pre-increment. Static analysis found the
>> issue on the count > POLLING_LLT_THRESHOLD check always being false since
>> the loop currently just iterates once.
> 
> But that is a very strange 'loop bottom'.
> 
> ...
>> diff --git a/drivers/staging/rtl8188eu/hal/rtl8188e_hal_init.c
>> b/drivers/staging/rtl8188eu/hal/rtl8188e_hal_init.c
>> index d1086699f952..db57f04e7e56 100644
>> --- a/drivers/staging/rtl8188eu/hal/rtl8188e_hal_init.c
>> +++ b/drivers/staging/rtl8188eu/hal/rtl8188e_hal_init.c
>> @@ -185,7 +185,7 @@ static s32 _LLTWrite(struct adapter *padapter, u32 address, u32 data)
>>  			break;
>>  		}
>>  		udelay(5);
>> -	} while (count++);
>> +	} while (++count);
> 
> Unless 'count' is negative that might as well be 'while (1)'
> with count incremented elsewhere.
> Perhaps the loop top should be:
> 	for (count = 0;; count++) {

I'll rework it, thanks for the input.

> 
>    David
> 
> -
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