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From: Arnaud POULIQUEN <arnaud.pouliquen@st.com>
To: "Clément Leger" <cleger@kalray.eu>
Cc: Ohad Ben-Cohen <ohad@wizery.com>,
	Bjorn Andersson <bjorn.andersson@linaro.org>,
	Jonathan Corbet <corbet@lwn.net>, Shawn Guo <shawnguo@kernel.org>,
	Sascha Hauer <s.hauer@pengutronix.de>,
	linux-remoteproc <linux-remoteproc@vger.kernel.org>,
	Pengutronix Kernel Team <kernel@pengutronix.de>,
	Fabio Estevam <festevam@gmail.com>,
	NXP Linux Team <linux-imx@nxp.com>,
	Andy Gross <agross@kernel.org>,
	Patrice Chotard <patrice.chotard@st.com>,
	linux-doc <linux-doc@vger.kernel.org>,
	linux-kernel <linux-kernel@vger.kernel.org>,
	linux-arm-kernel <linux-arm-kernel@lists.infradead.org>,
	linux-arm-msm <linux-arm-msm@vger.kernel.org>,
	Loic PALLARDY <loic.pallardy@st.com>, s-anna <s-anna@ti.com>,
	Mathieu Poirier <mathieu.poirier@linaro.org>
Subject: Re: [PATCH v4 1/5] remoteproc: Use u64 len for da_to_va
Date: Tue, 11 Feb 2020 18:24:07 +0100	[thread overview]
Message-ID: <63c2949f-c1d6-c0aa-b123-906630e3f028@st.com> (raw)
In-Reply-To: <884697376.3644142.1581439161953.JavaMail.zimbra@kalray.eu>



On 2/11/20 5:39 PM, Clément Leger wrote:
> Hi Arnaud,
> 
> ----- On 11 Feb, 2020, at 16:53, Arnaud Pouliquen arnaud.pouliquen@st.com wrote:
> 
>> On 2/10/20 5:22 PM, Clement Leger wrote:
>>> With upcoming changes in elf loader for elf64 support, section size will
>>> be a u64. When used with da_to_va, this will potentially lead to
>>> overflow if using the current "int" type for len argument. Change
>>> da_to_va prototype to use a u64 for len and fix all users of this
>>> function.
>>>
>>> Signed-off-by: Clement Leger <cleger@kalray.eu>
>>> ---
>>>  drivers/remoteproc/imx_rproc.c           | 11 ++++++-----
>>>  drivers/remoteproc/keystone_remoteproc.c |  4 ++--
>>>  drivers/remoteproc/qcom_q6v5_adsp.c      |  2 +-
>>>  drivers/remoteproc/qcom_q6v5_mss.c       |  2 +-
>>>  drivers/remoteproc/qcom_q6v5_pas.c       |  2 +-
>>>  drivers/remoteproc/qcom_q6v5_wcss.c      |  2 +-
>>>  drivers/remoteproc/qcom_wcnss.c          |  2 +-
>>>  drivers/remoteproc/remoteproc_core.c     |  2 +-
>>>  drivers/remoteproc/remoteproc_internal.h |  2 +-
>>>  drivers/remoteproc/st_slim_rproc.c       |  4 ++--
>>>  drivers/remoteproc/wkup_m3_rproc.c       |  4 ++--
>>>  include/linux/remoteproc.h               |  2 +-
>>>  12 files changed, 20 insertions(+), 19 deletions(-)
>>>
>>> diff --git a/drivers/remoteproc/imx_rproc.c b/drivers/remoteproc/imx_rproc.c
>>> index 3e72b6f38d4b..f497f5b49b18 100644
>>> --- a/drivers/remoteproc/imx_rproc.c
>>> +++ b/drivers/remoteproc/imx_rproc.c
>>> @@ -186,7 +186,7 @@ static int imx_rproc_stop(struct rproc *rproc)
>>>  }
>>>  
>>>  static int imx_rproc_da_to_sys(struct imx_rproc *priv, u64 da,
>>> -			       int len, u64 *sys)
>>> +			       u64 len, u64 *sys)
>>>  {
>>>  	const struct imx_rproc_dcfg *dcfg = priv->dcfg;
>>>  	int i;
>>> @@ -203,19 +203,19 @@ static int imx_rproc_da_to_sys(struct imx_rproc *priv, u64
>>> da,
>>>  		}
>>>  	}
>>>  
>>> -	dev_warn(priv->dev, "Translation failed: da = 0x%llx len = 0x%x\n",
>>> +	dev_warn(priv->dev, "Translation failed: da = 0x%llx len = 0x%llx\n",
>>>  		 da, len);
>>>  	return -ENOENT;
>>>  }
>>>  
>>> -static void *imx_rproc_da_to_va(struct rproc *rproc, u64 da, int len)
>>> +static void *imx_rproc_da_to_va(struct rproc *rproc, u64 da, u64 len)
>>>  {
>>>  	struct imx_rproc *priv = rproc->priv;
>>>  	void *va = NULL;
>>>  	u64 sys;
>>>  	int i;
>>>  
>>> -	if (len <= 0)
>>> +	if (len == 0)
>>>  		return NULL;
>>>  
>>>  	/*
>>> @@ -235,7 +235,8 @@ static void *imx_rproc_da_to_va(struct rproc *rproc, u64 da,
>>> int len)
>>>  		}
>>>  	}
>>>  
>>> -	dev_dbg(&rproc->dev, "da = 0x%llx len = 0x%x va = 0x%p\n", da, len, va);
>>> +	dev_dbg(&rproc->dev, "da = 0x%llx len = 0x%llx va = 0x%p\n",
>>> +		da, len, va);
>>>  
>>>  	return va;
>>>  }
>>> diff --git a/drivers/remoteproc/keystone_remoteproc.c
>>> b/drivers/remoteproc/keystone_remoteproc.c
>>> index 5c4658f00b3d..466093f48814 100644
>>> --- a/drivers/remoteproc/keystone_remoteproc.c
>>> +++ b/drivers/remoteproc/keystone_remoteproc.c
>>> @@ -246,7 +246,7 @@ static void keystone_rproc_kick(struct rproc *rproc, int
>>> vqid)
>>>   * can be used either by the remoteproc core for loading (when using kernel
>>>   * remoteproc loader), or by any rpmsg bus drivers.
>>>   */
>>> -static void *keystone_rproc_da_to_va(struct rproc *rproc, u64 da, int len)
>>> +static void *keystone_rproc_da_to_va(struct rproc *rproc, u64 da, u64 len)
>>>  {
>>>  	struct keystone_rproc *ksproc = rproc->priv;
>>>  	void __iomem *va = NULL;
>>> @@ -255,7 +255,7 @@ static void *keystone_rproc_da_to_va(struct rproc *rproc,
>>> u64 da, int len)
>>>  	size_t size;
>>>  	int i;
>>>  
>>> -	if (len <= 0)
>>> +	if (len == 0)
>>>  		return NULL;
>>>  
>>>  	for (i = 0; i < ksproc->num_mems; i++) {
>>> diff --git a/drivers/remoteproc/qcom_q6v5_adsp.c
>>> b/drivers/remoteproc/qcom_q6v5_adsp.c
>>> index e953886b2eb7..7518e67a49e5 100644
>>> --- a/drivers/remoteproc/qcom_q6v5_adsp.c
>>> +++ b/drivers/remoteproc/qcom_q6v5_adsp.c
>>> @@ -270,7 +270,7 @@ static int adsp_stop(struct rproc *rproc)
>>>  	return ret;
>>>  }
>>>  
>>> -static void *adsp_da_to_va(struct rproc *rproc, u64 da, int len)
>>> +static void *adsp_da_to_va(struct rproc *rproc, u64 da, u64 len)
>>>  {
>>>  	struct qcom_adsp *adsp = (struct qcom_adsp *)rproc->priv;
>>>  	int offset;
>>> diff --git a/drivers/remoteproc/qcom_q6v5_mss.c
>>> b/drivers/remoteproc/qcom_q6v5_mss.c
>>> index 471128a2e723..248febde6fc1 100644
>>> --- a/drivers/remoteproc/qcom_q6v5_mss.c
>>> +++ b/drivers/remoteproc/qcom_q6v5_mss.c
>>> @@ -1148,7 +1148,7 @@ static int q6v5_stop(struct rproc *rproc)
>>>  	return 0;
>>>  }
>>>  
>>> -static void *q6v5_da_to_va(struct rproc *rproc, u64 da, int len)
>>> +static void *q6v5_da_to_va(struct rproc *rproc, u64 da, u64 len)
>>>  {
>>>  	struct q6v5 *qproc = rproc->priv;
>>>  	int offset;
>>> diff --git a/drivers/remoteproc/qcom_q6v5_pas.c
>>> b/drivers/remoteproc/qcom_q6v5_pas.c
>>> index db4b3c4bacd7..cf2cd609c90d 100644
>>> --- a/drivers/remoteproc/qcom_q6v5_pas.c
>>> +++ b/drivers/remoteproc/qcom_q6v5_pas.c
>>> @@ -159,7 +159,7 @@ static int adsp_stop(struct rproc *rproc)
>>>  	return ret;
>>>  }
>>>  
>>> -static void *adsp_da_to_va(struct rproc *rproc, u64 da, int len)
>>> +static void *adsp_da_to_va(struct rproc *rproc, u64 da, u64 len)
>>>  {
>>>  	struct qcom_adsp *adsp = (struct qcom_adsp *)rproc->priv;
>>>  	int offset;
>>> diff --git a/drivers/remoteproc/qcom_q6v5_wcss.c
>>> b/drivers/remoteproc/qcom_q6v5_wcss.c
>>> index f93e1e4a1cc0..3a6b82a16961 100644
>>> --- a/drivers/remoteproc/qcom_q6v5_wcss.c
>>> +++ b/drivers/remoteproc/qcom_q6v5_wcss.c
>>> @@ -406,7 +406,7 @@ static int q6v5_wcss_stop(struct rproc *rproc)
>>>  	return 0;
>>>  }
>>>  
>>> -static void *q6v5_wcss_da_to_va(struct rproc *rproc, u64 da, int len)
>>> +static void *q6v5_wcss_da_to_va(struct rproc *rproc, u64 da, u64 len)
>>>  {
>>>  	struct q6v5_wcss *wcss = rproc->priv;
>>>  	int offset;
>>> diff --git a/drivers/remoteproc/qcom_wcnss.c b/drivers/remoteproc/qcom_wcnss.c
>>> index dc135754bb9c..f893219e45a8 100644
>>> --- a/drivers/remoteproc/qcom_wcnss.c
>>> +++ b/drivers/remoteproc/qcom_wcnss.c
>>> @@ -287,7 +287,7 @@ static int wcnss_stop(struct rproc *rproc)
>>>  	return ret;
>>>  }
>>>  
>>> -static void *wcnss_da_to_va(struct rproc *rproc, u64 da, int len)
>>> +static void *wcnss_da_to_va(struct rproc *rproc, u64 da, u64 len)
>>>  {
>>>  	struct qcom_wcnss *wcnss = (struct qcom_wcnss *)rproc->priv;
>>>  	int offset;
>>> diff --git a/drivers/remoteproc/remoteproc_core.c
>>> b/drivers/remoteproc/remoteproc_core.c
>>> index 307df98347ba..9e6d3c6a60ee 100644
>>> --- a/drivers/remoteproc/remoteproc_core.c
>>> +++ b/drivers/remoteproc/remoteproc_core.c
>>> @@ -185,7 +185,7 @@ EXPORT_SYMBOL(rproc_va_to_pa);
>>>   * here the output of the DMA API for the carveouts, which should be more
>>>   * correct.
>>>   */
>>> -void *rproc_da_to_va(struct rproc *rproc, u64 da, int len)
>>> +void *rproc_da_to_va(struct rproc *rproc, u64 da, u64 len)
>>
>> This function is exported, don't see any update in consequence...
>> references:
>> https://elixir.bootlin.com/linux/v5.6-rc1/ident/rproc_da_to_va
>> For instance the function rproc_trace_read use it. it quite strange that my gcc
>> does not warns for the cast but i suppose that some could.
> 
> Agreed, even if len should never have been a signed type since it can't be
> negative. I will try to fix all callers.
> 
>> An indirect consequence is that the len field in rproc_mem_entry struct should
>> probably been updated to u64 to be aligned.
> 
> Ok, I will do that once we settle on the type of len.
> 
>>
>> I'm still wondering about the use of size_t instead,which seems more rational
>> from my window.
>> So i you or Mathieu remember it was decided to use u64, please could remind me
>> the arguments?
> 
> I tried to find the notes of a meeting we had for OpenAMP but I did not found
> them. Anyway, the argument was coming from Tomas or someone else, (I can't
> remember) talking about a 32 bits CPU executing code on a 64 bits accelerator.
> In that case, the size_t type could fail due to being only 32bits on the host
> CPU but larger than 4G.
> 
> However, I can't say if it's a real usecase or not... All I can say is
> that keeping it open is probably better if one day somebody comes with such
> architecture.
> 
>> As an alternative a check should be added for 32 bits processors to ensure that
>> the size is not higher than
>> its address range capability...
> 
> Agreed.
> I was even thinking about a mecanism for remoteproc drivers to declare the type
> of supported elfs files (such as EM_*, ELFCLASS* and other needed thing).
> Or should it be supported by overriding .sanity_check in drivers  to reject
> elf64 for instance ?
> 
> Since elf is a "specific format" and that rproc can support other formats,
> I did not want to add a specific elf_sanity_check field to rproc ops.
Agree, platform driver as to check the format it can support, elf, bin, properitay format....
To check the size, the da_to_va ops seems a good candidate as called for loaded segments and memories.
So ok to delegate the check to the platform driver.

Regards
Arnaud

> 
> Regards,
> 
> Clément
> 
>>
>> Regards
>> Arnaud
>>
>>>  {
>>>  	struct rproc_mem_entry *carveout;
>>>  	void *ptr = NULL;
>>> diff --git a/drivers/remoteproc/remoteproc_internal.h
>>> b/drivers/remoteproc/remoteproc_internal.h
>>> index 493ef9262411..004867061721 100644
>>> --- a/drivers/remoteproc/remoteproc_internal.h
>>> +++ b/drivers/remoteproc/remoteproc_internal.h
>>> @@ -50,7 +50,7 @@ void rproc_exit_sysfs(void);
>>>  void rproc_free_vring(struct rproc_vring *rvring);
>>>  int rproc_alloc_vring(struct rproc_vdev *rvdev, int i);
>>>  
>>> -void *rproc_da_to_va(struct rproc *rproc, u64 da, int len);
>>> +void *rproc_da_to_va(struct rproc *rproc, u64 da, u64 len);
>>>  phys_addr_t rproc_va_to_pa(void *cpu_addr);
>>>  int rproc_trigger_recovery(struct rproc *rproc);
>>>  
>>> diff --git a/drivers/remoteproc/st_slim_rproc.c
>>> b/drivers/remoteproc/st_slim_rproc.c
>>> index 04492fead3c8..fc01cd879b60 100644
>>> --- a/drivers/remoteproc/st_slim_rproc.c
>>> +++ b/drivers/remoteproc/st_slim_rproc.c
>>> @@ -174,7 +174,7 @@ static int slim_rproc_stop(struct rproc *rproc)
>>>  	return 0;
>>>  }
>>>  
>>> -static void *slim_rproc_da_to_va(struct rproc *rproc, u64 da, int len)
>>> +static void *slim_rproc_da_to_va(struct rproc *rproc, u64 da, u64 len)
>>>  {
>>>  	struct st_slim_rproc *slim_rproc = rproc->priv;
>>>  	void *va = NULL;
>>> @@ -191,7 +191,7 @@ static void *slim_rproc_da_to_va(struct rproc *rproc, u64
>>> da, int len)
>>>  		}
>>>  	}
>>>  
>>> -	dev_dbg(&rproc->dev, "da = 0x%llx len = 0x%x va = 0x%pK\n",
>>> +	dev_dbg(&rproc->dev, "da = 0x%llx len = 0x%llx va = 0x%pK\n",
>>>  		da, len, va);
>>>  
>>>  	return va;
>>> diff --git a/drivers/remoteproc/wkup_m3_rproc.c
>>> b/drivers/remoteproc/wkup_m3_rproc.c
>>> index 3984e585c847..91485b467407 100644
>>> --- a/drivers/remoteproc/wkup_m3_rproc.c
>>> +++ b/drivers/remoteproc/wkup_m3_rproc.c
>>> @@ -80,14 +80,14 @@ static int wkup_m3_rproc_stop(struct rproc *rproc)
>>>  	return 0;
>>>  }
>>>  
>>> -static void *wkup_m3_rproc_da_to_va(struct rproc *rproc, u64 da, int len)
>>> +static void *wkup_m3_rproc_da_to_va(struct rproc *rproc, u64 da, u64 len)
>>>  {
>>>  	struct wkup_m3_rproc *wkupm3 = rproc->priv;
>>>  	void *va = NULL;
>>>  	int i;
>>>  	u32 offset;
>>>  
>>> -	if (len <= 0)
>>> +	if (len == 0)
>>>  		return NULL;
>>>  
>>>  	for (i = 0; i < WKUPM3_MEM_MAX; i++) {
>>> diff --git a/include/linux/remoteproc.h b/include/linux/remoteproc.h
>>> index 16ad66683ad0..f84bd5fe0211 100644
>>> --- a/include/linux/remoteproc.h
>>> +++ b/include/linux/remoteproc.h
>>> @@ -374,7 +374,7 @@ struct rproc_ops {
>>>  	int (*start)(struct rproc *rproc);
>>>  	int (*stop)(struct rproc *rproc);
>>>  	void (*kick)(struct rproc *rproc, int vqid);
>>> -	void * (*da_to_va)(struct rproc *rproc, u64 da, int len);
>>> +	void * (*da_to_va)(struct rproc *rproc, u64 da, u64 len);
>>>  	int (*parse_fw)(struct rproc *rproc, const struct firmware *fw);
>>>  	int (*handle_rsc)(struct rproc *rproc, u32 rsc_type, void *rsc,
>>>  			  int offset, int avail);

  reply	other threads:[~2020-02-11 17:24 UTC|newest]

Thread overview: 63+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <20200129163013.GA16538@xps15>
2020-02-04 14:33 ` [PATCH v2 1/2] remoteproc: Use u64 len for da_to_va Clement Leger
2020-02-04 14:33   ` [PATCH v2 2/2] remoteproc: Add elf64 support in elf loader Clement Leger
2020-02-04 16:27   ` [PATCH v2 1/2] remoteproc: Use u64 len for da_to_va Arnaud POULIQUEN
2020-02-04 17:10     ` Clément Leger
2020-02-04 17:42       ` Arnaud POULIQUEN
2020-02-04 17:44 ` [PATCH v3 0/2] remoteproc: Add elf64 support to elf loader Clement Leger
2020-02-04 17:44   ` [PATCH v3 1/2] remoteproc: Use u64 len for da_to_va Clement Leger
2020-02-05 21:06     ` Mathieu Poirier
2020-02-04 17:44   ` [PATCH v3 2/2] remoteproc: Add elf64 support in elf loader Clement Leger
2020-02-05 22:49     ` Mathieu Poirier
2020-02-06  8:37       ` Clément Leger
2020-02-06 15:05         ` Clément Leger
2020-02-06 17:48           ` Mathieu Poirier
2020-02-07  7:57             ` Clément Leger
2020-02-10 16:22               ` [PATCH v4 0/5] remoteproc: Add elf64 support Clement Leger
2020-02-10 16:22                 ` [PATCH v4 1/5] remoteproc: Use u64 len for da_to_va Clement Leger
2020-02-11 15:53                   ` Arnaud POULIQUEN
2020-02-11 16:39                     ` Clément Leger
2020-02-11 17:24                       ` Arnaud POULIQUEN [this message]
2020-02-11 22:37                       ` Mathieu Poirier
2020-02-12 10:37                         ` Clément Leger
2020-02-12 21:59                           ` Mathieu Poirier
2020-02-18 10:10                             ` Clément Leger
2020-02-18 17:01                               ` Mathieu Poirier
2020-02-10 16:22                 ` [PATCH v4 2/5] remoteproc: Use u64 type for boot_addr Clement Leger
2020-02-10 16:22                 ` [PATCH v4 3/5] remoteproc: Add elf helpers to access elf64 and elf32 fields Clement Leger
2020-02-10 16:22                 ` [PATCH v4 4/5] remoteproc: Add elf64 support in elf loader Clement Leger
2020-02-10 16:22                 ` [PATCH v4 5/5] remoteproc: Adapt coredump to generate correct elf type Clement Leger
2020-02-11 23:11                   ` Mathieu Poirier
2020-02-11 15:57                 ` [PATCH v4 0/5] remoteproc: Add elf64 support Arnaud POULIQUEN
2020-02-11 23:12                   ` Mathieu Poirier
2020-02-12  8:15                     ` Arnaud POULIQUEN
2020-03-02  9:38                 ` [PATCH v5 0/8] " Clement Leger
2020-03-02  9:38                   ` [PATCH v5 1/8] remoteproc: Use size_t type for len in da_to_va Clement Leger
2020-03-02 23:06                     ` Bjorn Andersson
2020-03-09 17:52                     ` Mathieu Poirier
2020-03-27  7:37                     ` Oleksij Rempel
2020-03-02  9:38                   ` [PATCH v5 2/8] remoteproc: Use size_t instead of int for rproc_mem_entry len Clement Leger
2020-03-02 23:07                     ` Bjorn Andersson
2020-03-09 19:21                     ` Mathieu Poirier
2020-03-02  9:38                   ` [PATCH v5 3/8] remoteproc: Use u64 type for boot_addr Clement Leger
2020-03-02 23:08                     ` Bjorn Andersson
2020-03-09 19:52                     ` Mathieu Poirier
2020-03-10  7:59                       ` Clément Leger
2020-03-10 19:32                         ` Bjorn Andersson
2020-03-02  9:38                   ` [PATCH v5 4/8] remoteproc: Add elf helpers to access elf64 and elf32 fields Clement Leger
2020-03-02 23:12                     ` Bjorn Andersson
2020-03-09 19:56                     ` Mathieu Poirier
2020-03-02  9:38                   ` [PATCH v5 5/8] remoteproc: Rename rproc_elf_sanity_check for elf32 Clement Leger
2020-03-02 23:13                     ` Bjorn Andersson
2020-03-03  8:02                       ` Clément Leger
2020-03-10  0:00                         ` Bjorn Andersson
2020-03-10 15:20                           ` Mathieu Poirier
2020-03-10 15:38                             ` Clément Leger
2020-03-10 19:18                               ` Mathieu Poirier
2020-03-10 19:30                               ` Bjorn Andersson
2020-03-02  9:39                   ` [PATCH v5 6/8] remoteproc: Add elf64 support in elf loader Clement Leger
2020-03-02  9:39                   ` [PATCH v5 7/8] remoteproc: Allow overriding only sanity_check Clement Leger
2020-03-02  9:39                   ` [PATCH v5 8/8] remoteproc: Adapt coredump to generate correct elf type Clement Leger
2020-03-03 22:01                     ` Bjorn Andersson
2020-03-09 20:32                     ` Mathieu Poirier
2020-03-09 23:57                       ` Bjorn Andersson
2020-03-10  8:12                         ` Clément Leger

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