linux-kernel - Re: [PATCH v4 1/5] firmware: stratix10-svc: Add mutex lock and unlock in stratix10 memory allocation/free

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]

Message-ID: <b92fc5e6-d39f-4e17-a7e9-bd121650b41b@altera.com>
Date: Wed, 11 Jun 2025 18:10:00 +0530
From: Mahesh Rao <mahesh.rao@...era.com>
To: Matthew Gerlach <matthew.gerlach@...era.com>,
 Dinh Nguyen <dinguyen@...nel.org>, Rob Herring <robh@...nel.org>,
 Krzysztof Kozlowski <krzk+dt@...nel.org>, Conor Dooley <conor+dt@...nel.org>
Cc: linux-kernel@...r.kernel.org, devicetree@...r.kernel.org
Subject: Re: [PATCH v4 1/5] firmware: stratix10-svc: Add mutex lock and unlock
 in stratix10 memory allocation/free

Hi Matthew,

On 10-06-2025 09:36 pm, Matthew Gerlach wrote:
> 
> On 6/10/25 8:37 AM, Mahesh Rao via B4 Relay wrote:
>> From: Mahesh Rao <mahesh.rao@...era.com>
>>
>> This commit adds a mutex lock to protect the
>> stratix10_svc_allocate_memory and
>> stratix10_svc_free_memory functions to ensure
>> thread safety when allocating and freeing memory.
>> This prevents potential race conditions and ensures
>> synchronization.
>>
>> Signed-off-by: Mahesh Rao <mahesh.rao@...era.com>
>> Reviewed-by: Matthew Gerlach <matthew.gerlach@...era.com>
>> ---
>>   drivers/firmware/stratix10-svc.c | 30 +++++++++++++++++++++++-------
>>   1 file changed, 23 insertions(+), 7 deletions(-)
>>
>> diff --git a/drivers/firmware/stratix10-svc.c b/drivers/firmware/ 
>> stratix10-svc.c
>> index 
>> e3f990d888d71829f0ab22b8a59aa7af0316bea0..955468555738b2031dfcf6dc4db7dbf11ccc482c 100644
>> --- a/drivers/firmware/stratix10-svc.c
>> +++ b/drivers/firmware/stratix10-svc.c
>> @@ -1,6 +1,7 @@
>>   // SPDX-License-Identifier: GPL-2.0
>>   /*
>>    * Copyright (C) 2017-2018, Intel Corporation
>> + * Copyright (C) 2025, Altera Corporation
>>    */
>>   #include <linux/completion.h>
>> @@ -171,6 +172,10 @@ struct stratix10_svc_chan {
>>   static LIST_HEAD(svc_ctrl);
>>   static LIST_HEAD(svc_data_mem);
>> +/* svc_mem_lock protects access to the svc_data_mem list for
>> + * concurrent multi-client operations
>> + */
>> +static DEFINE_MUTEX(svc_mem_lock);
>>   /**
>>    * svc_pa_to_va() - translate physical address to virtual address
>> @@ -182,14 +187,17 @@ static LIST_HEAD(svc_data_mem);
>>   static void *svc_pa_to_va(unsigned long addr)
>>   {
>>       struct stratix10_svc_data_mem *pmem;
>> +    void *ret = NULL;
>>       pr_debug("claim back P-addr=0x%016x\n", (unsigned int)addr);
>> +    mutex_lock(&svc_mem_lock);
>>       list_for_each_entry(pmem, &svc_data_mem, node)
>> -        if (pmem->paddr == addr)
>> -            return pmem->vaddr;
>> -
>> -    /* physical address is not found */
>> -    return NULL;
>> +        if (pmem->paddr == addr) {
>> +            /* physical address is found */
>> +            ret = pmem->vaddr;
> 
> I think you want a "break;" here.
> 
> 
> Matthew Geralch

Will make the change.
> 
>> +        }
>> +    mutex_unlock(&svc_mem_lock);
>> +    return ret;
>>   }
>>   /**
>> @@ -990,6 +998,7 @@ int stratix10_svc_send(struct stratix10_svc_chan