linux-kernel - Re: [PATCH V2 2/3] perf/x86/intel/uncore: Record the size of mapped area

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: Windows password security audit tool. GUI, reports in PDF.

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

Date:   Thu, 28 May 2020 09:44:45 -0400
From:   "Liang, Kan" <kan.liang@...ux.intel.com>
To:     Andi Kleen <ak@...ux.intel.com>
Cc:     peterz@...radead.org, mingo@...hat.com,
        linux-kernel@...r.kernel.org, David.Laight@...lab.com
Subject: Re: [PATCH V2 2/3] perf/x86/intel/uncore: Record the size of mapped
 area



On 5/28/2020 9:29 AM, Andi Kleen wrote:
> On Thu, May 28, 2020 at 06:15:26AM -0700, kan.liang@...ux.intel.com wrote:
>> -	box->io_addr = ioremap(addr, SNB_UNCORE_PCI_IMC_MAP_SIZE);
>> +	if (!type->mmio_map_size) {
>> +		pr_warn("perf uncore: Cannot ioremap for %s. Size of map area is 0.\n",
>> +			type->name);
>> +		return;
>> +	}
> 
> Is that likely that the size is 0?

In case someone forgets to set mmio_map_size.

> 
> In any case you have to test the return value of ioremap. So I would rather
> test the address for 0 than the size.

The box->io_addr is checked now, but there is no warning message.
I will remove the check for mmio_map_size, and add a warning message for 
the check of box->io_addr.

Thanks,
Kan