diff mbox

[dpdk-dev] pci: fix check uio bind

Message ID 1508411909-63954-1-git-send-email-jianfeng.tan@intel.com (mailing list archive)
State Superseded, archived
Headers

Checks

Context Check Description
ci/checkpatch success coding style OK
ci/Intel-compilation success Compilation OK

Commit Message

Jianfeng Tan Oct. 19, 2017, 11:18 a.m. UTC 
  When checking if any devices bound to uio, we did not exclud
those which are blacklisted (or in the case that a whitelist
is specified).

This patch fixes it by only checking whitelisted devices.

Fixes: 815c7deaed2d ("pci: get IOMMU class on Linux")

Signed-off-by: Jianfeng Tan <jianfeng.tan@intel.com>
---
 lib/librte_eal/linuxapp/eal/eal_pci.c | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

Comments

Gaëtan Rivet Oct. 19, 2017, 11:42 a.m. UTC | #1 
Hi Jianfeng,

On Thu, Oct 19, 2017 at 11:18:29AM +0000, Jianfeng Tan wrote:
> When checking if any devices bound to uio, we did not exclud
> those which are blacklisted (or in the case that a whitelist
> is specified).
> 
> This patch fixes it by only checking whitelisted devices.
> 
> Fixes: 815c7deaed2d ("pci: get IOMMU class on Linux")
> 
> Signed-off-by: Jianfeng Tan <jianfeng.tan@intel.com>
> ---
>  lib/librte_eal/linuxapp/eal/eal_pci.c | 18 ++++++++++++++++++
>  1 file changed, 18 insertions(+)
> 
> diff --git a/lib/librte_eal/linuxapp/eal/eal_pci.c b/lib/librte_eal/linuxapp/eal/eal_pci.c
> index b4dbf95..2b23d67 100644
> --- a/lib/librte_eal/linuxapp/eal/eal_pci.c
> +++ b/lib/librte_eal/linuxapp/eal/eal_pci.c
> @@ -516,8 +516,26 @@ static inline int
>  pci_one_device_bound_uio(void)
>  {
>  	struct rte_pci_device *dev = NULL;
> +	struct rte_devargs *devargs;
> +	int check_all = 1;
> +	int need_check;
> +
> +	if (rte_pci_bus.bus.conf.scan_mode == RTE_BUS_SCAN_WHITELIST)
> +		check_all = 0;
>  
>  	FOREACH_DEVICE_ON_PCIBUS(dev) {
> +		devargs = dev->device.devargs;
> +
> +		need_check = 0;
> +		if (check_all)

Unless I'm mistaken, you will check blacklisted devices as well here.
The condition should be something like:

if (check_all && devargs == NULL)

Which means that both ifs can be refactored as

if ((check_all ^ (devargs != NULL)) == 0)
        continue;

Removing need_check. But it can be hard to read.

> +			need_check = 1;
> +		else if (devargs != NULL &&
> +			 devargs->policy == RTE_DEV_WHITELISTED)
> +			need_check = 1;
> +
> +		if (!need_check)
> +			continue;
> +
>  		if (dev->kdrv == RTE_KDRV_IGB_UIO ||
>  		   dev->kdrv == RTE_KDRV_UIO_GENERIC) {
>  			return 1;
> -- 
> 2.7.4
>
Jianfeng Tan Oct. 20, 2017, 4:47 p.m. UTC | #2 
Hi Gaëtan,


On 10/19/2017 7:42 PM, Gaëtan Rivet wrote:
> Hi Jianfeng,
>
> On Thu, Oct 19, 2017 at 11:18:29AM +0000, Jianfeng Tan wrote:
>> When checking if any devices bound to uio, we did not exclud
>> those which are blacklisted (or in the case that a whitelist
>> is specified).
>>
>> This patch fixes it by only checking whitelisted devices.
>>
>> Fixes: 815c7deaed2d ("pci: get IOMMU class on Linux")
>>
>> Signed-off-by: Jianfeng Tan <jianfeng.tan@intel.com>
>> ---
>>   lib/librte_eal/linuxapp/eal/eal_pci.c | 18 ++++++++++++++++++
>>   1 file changed, 18 insertions(+)
>>
>> diff --git a/lib/librte_eal/linuxapp/eal/eal_pci.c b/lib/librte_eal/linuxapp/eal/eal_pci.c
>> index b4dbf95..2b23d67 100644
>> --- a/lib/librte_eal/linuxapp/eal/eal_pci.c
>> +++ b/lib/librte_eal/linuxapp/eal/eal_pci.c
>> @@ -516,8 +516,26 @@ static inline int
>>   pci_one_device_bound_uio(void)
>>   {
>>   	struct rte_pci_device *dev = NULL;
>> +	struct rte_devargs *devargs;
>> +	int check_all = 1;
>> +	int need_check;
>> +
>> +	if (rte_pci_bus.bus.conf.scan_mode == RTE_BUS_SCAN_WHITELIST)
>> +		check_all = 0;
>>   
>>   	FOREACH_DEVICE_ON_PCIBUS(dev) {
>> +		devargs = dev->device.devargs;
>> +
>> +		need_check = 0;
>> +		if (check_all)
> Unless I'm mistaken, you will check blacklisted devices as well here.

Thank you for pointing out this.

I was referring to rte_pci_probe(), which also only check "probe_all" 
and (devargs && RTE_DEV_WHITELISTED); but turns out it double checks the 
blacklisted devices in rte_pci_probe_one_driver().

I'll fix it.

> The condition should be something like:
>
> if (check_all && devargs == NULL)

> Which means that both ifs can be refactored as
>
> if ((check_all ^ (devargs != NULL)) == 0)
>          continue;
>
> Removing need_check. But it can be hard to read.

Yes, I prefer to make it easy to understand. Please let me know if you 
are OK with below code (remove check_all):

         FOREACH_DEVICE_ON_PCIBUS(dev) {
                 devargs = dev->device.devargs;

                 need_check = 0;
                 switch (rte_pci_bus.bus.conf.scan_mode) {
                 case RTE_BUS_SCAN_UNDEFINED:
                         need_check = 1;
                         break;
                 case RTE_BUS_SCAN_WHITELIST:
                         if (devargs && devargs->policy == 
RTE_DEV_WHITELISTED)
                                 need_check = 1;
                         break;
                 case RTE_BUS_SCAN_BLACKLIST:
                         if (!devargs || devargs->policy != 
RTE_DEV_BLACKLISTED)
                                 need_check = 1;
                         break;
                 }

                 if (!need_check)
                         continue;
...

Thanks,
Jianfeng
Gaëtan Rivet Oct. 20, 2017, 8:08 p.m. UTC | #3 
On Sat, Oct 21, 2017 at 12:47:14AM +0800, Tan, Jianfeng wrote:
> Hi Gaëtan,
> 
> 
> On 10/19/2017 7:42 PM, Gaëtan Rivet wrote:
> >Hi Jianfeng,
> >
> >On Thu, Oct 19, 2017 at 11:18:29AM +0000, Jianfeng Tan wrote:
> >>When checking if any devices bound to uio, we did not exclud
> >>those which are blacklisted (or in the case that a whitelist
> >>is specified).
> >>
> >>This patch fixes it by only checking whitelisted devices.
> >>
> >>Fixes: 815c7deaed2d ("pci: get IOMMU class on Linux")
> >>
> >>Signed-off-by: Jianfeng Tan <jianfeng.tan@intel.com>
> >>---
> >>  lib/librte_eal/linuxapp/eal/eal_pci.c | 18 ++++++++++++++++++
> >>  1 file changed, 18 insertions(+)
> >>
> >>diff --git a/lib/librte_eal/linuxapp/eal/eal_pci.c b/lib/librte_eal/linuxapp/eal/eal_pci.c
> >>index b4dbf95..2b23d67 100644
> >>--- a/lib/librte_eal/linuxapp/eal/eal_pci.c
> >>+++ b/lib/librte_eal/linuxapp/eal/eal_pci.c
> >>@@ -516,8 +516,26 @@ static inline int
> >>  pci_one_device_bound_uio(void)
> >>  {
> >>  	struct rte_pci_device *dev = NULL;
> >>+	struct rte_devargs *devargs;
> >>+	int check_all = 1;
> >>+	int need_check;
> >>+
> >>+	if (rte_pci_bus.bus.conf.scan_mode == RTE_BUS_SCAN_WHITELIST)
> >>+		check_all = 0;
> >>  	FOREACH_DEVICE_ON_PCIBUS(dev) {
> >>+		devargs = dev->device.devargs;
> >>+
> >>+		need_check = 0;
> >>+		if (check_all)
> >Unless I'm mistaken, you will check blacklisted devices as well here.
> 
> Thank you for pointing out this.
> 
> I was referring to rte_pci_probe(), which also only check "probe_all" and
> (devargs && RTE_DEV_WHITELISTED); but turns out it double checks the
> blacklisted devices in rte_pci_probe_one_driver().
> 
> I'll fix it.
> 
> >The condition should be something like:
> >
> >if (check_all && devargs == NULL)
> 
> >Which means that both ifs can be refactored as
> >
> >if ((check_all ^ (devargs != NULL)) == 0)
> >         continue;
> >
> >Removing need_check. But it can be hard to read.
> 
> Yes, I prefer to make it easy to understand. Please let me know if you are
> OK with below code (remove check_all):
> 
>         FOREACH_DEVICE_ON_PCIBUS(dev) {
>                 devargs = dev->device.devargs;
> 
>                 need_check = 0;
>                 switch (rte_pci_bus.bus.conf.scan_mode) {
>                 case RTE_BUS_SCAN_UNDEFINED:
>                         need_check = 1;
>                         break;
>                 case RTE_BUS_SCAN_WHITELIST:
>                         if (devargs && devargs->policy ==
> RTE_DEV_WHITELISTED)
>                                 need_check = 1;
>                         break;
>                 case RTE_BUS_SCAN_BLACKLIST:
>                         if (!devargs || devargs->policy !=
> RTE_DEV_BLACKLISTED)
>                                 need_check = 1;
>                         break;
>                 }
> 
>                 if (!need_check)
>                         continue;
> ...

I like the switch, two remarks however:

1. The SCAN_UNDEFINED basically means blacklist mode for the PCI bus.
   This is the reason probe_all was set by testing for WHITELIST
   mode: either of the other too would thus trigger the blacklist
   behavior.

   Thus, I think you could write a fallthrough case for UNDEFINED, that
   would go into the BLACKLIST mode.

2. For pointers in general I would test against NULL instead of using
   the unary '!'.
   I think it is the general policy in DPDK to always explicitly check
   against the constant value, but I personally think that for booleans
   like need_check the "not" operator is ok.
   So I will only highlight the !devargs :)

> 
> Thanks,
> Jianfeng
Jianfeng Tan Oct. 23, 2017, 3:20 a.m. UTC | #4 
Hi Gaëtan,

> -----Original Message-----
> From: Gaëtan Rivet [mailto:gaetan.rivet@6wind.com]
> Sent: Saturday, October 21, 2017 4:08 AM
> To: Tan, Jianfeng
> Cc: dev@dpdk.org; santosh.shukla@caviumnetworks.com;
> jerin.jacob@caviumnetworks.com; Burakov, Anatoly
> Subject: Re: [PATCH] pci: fix check uio bind
> 
> On Sat, Oct 21, 2017 at 12:47:14AM +0800, Tan, Jianfeng wrote:
> > Hi Gaëtan,
> >
> >
> > On 10/19/2017 7:42 PM, Gaëtan Rivet wrote:
> > >Hi Jianfeng,
> > >
> > >On Thu, Oct 19, 2017 at 11:18:29AM +0000, Jianfeng Tan wrote:
> > >>When checking if any devices bound to uio, we did not exclud
> > >>those which are blacklisted (or in the case that a whitelist
> > >>is specified).
> > >>
> > >>This patch fixes it by only checking whitelisted devices.
> > >>
> > >>Fixes: 815c7deaed2d ("pci: get IOMMU class on Linux")
> > >>
> > >>Signed-off-by: Jianfeng Tan <jianfeng.tan@intel.com>
> > >>---
> > >>  lib/librte_eal/linuxapp/eal/eal_pci.c | 18 ++++++++++++++++++
> > >>  1 file changed, 18 insertions(+)
> > >>
> > >>diff --git a/lib/librte_eal/linuxapp/eal/eal_pci.c
> b/lib/librte_eal/linuxapp/eal/eal_pci.c
> > >>index b4dbf95..2b23d67 100644
> > >>--- a/lib/librte_eal/linuxapp/eal/eal_pci.c
> > >>+++ b/lib/librte_eal/linuxapp/eal/eal_pci.c
> > >>@@ -516,8 +516,26 @@ static inline int
> > >>  pci_one_device_bound_uio(void)
> > >>  {
> > >>  	struct rte_pci_device *dev = NULL;
> > >>+	struct rte_devargs *devargs;
> > >>+	int check_all = 1;
> > >>+	int need_check;
> > >>+
> > >>+	if (rte_pci_bus.bus.conf.scan_mode == RTE_BUS_SCAN_WHITELIST)
> > >>+		check_all = 0;
> > >>  	FOREACH_DEVICE_ON_PCIBUS(dev) {
> > >>+		devargs = dev->device.devargs;
> > >>+
> > >>+		need_check = 0;
> > >>+		if (check_all)
> > >Unless I'm mistaken, you will check blacklisted devices as well here.
> >
> > Thank you for pointing out this.
> >
> > I was referring to rte_pci_probe(), which also only check "probe_all" and
> > (devargs && RTE_DEV_WHITELISTED); but turns out it double checks the
> > blacklisted devices in rte_pci_probe_one_driver().
> >
> > I'll fix it.
> >
> > >The condition should be something like:
> > >
> > >if (check_all && devargs == NULL)
> >
> > >Which means that both ifs can be refactored as
> > >
> > >if ((check_all ^ (devargs != NULL)) == 0)
> > >         continue;
> > >
> > >Removing need_check. But it can be hard to read.
> >
> > Yes, I prefer to make it easy to understand. Please let me know if you are
> > OK with below code (remove check_all):
> >
> >         FOREACH_DEVICE_ON_PCIBUS(dev) {
> >                 devargs = dev->device.devargs;
> >
> >                 need_check = 0;
> >                 switch (rte_pci_bus.bus.conf.scan_mode) {
> >                 case RTE_BUS_SCAN_UNDEFINED:
> >                         need_check = 1;
> >                         break;
> >                 case RTE_BUS_SCAN_WHITELIST:
> >                         if (devargs && devargs->policy ==
> > RTE_DEV_WHITELISTED)
> >                                 need_check = 1;
> >                         break;
> >                 case RTE_BUS_SCAN_BLACKLIST:
> >                         if (!devargs || devargs->policy !=
> > RTE_DEV_BLACKLISTED)
> >                                 need_check = 1;
> >                         break;
> >                 }
> >
> >                 if (!need_check)
> >                         continue;
> > ...
> 
> I like the switch, two remarks however:
> 
> 1. The SCAN_UNDEFINED basically means blacklist mode for the PCI bus.
>    This is the reason probe_all was set by testing for WHITELIST
>    mode: either of the other too would thus trigger the blacklist
>    behavior.
> 
>    Thus, I think you could write a fallthrough case for UNDEFINED, that
>    would go into the BLACKLIST mode.
> 
> 2. For pointers in general I would test against NULL instead of using
>    the unary '!'.
>    I think it is the general policy in DPDK to always explicitly check
>    against the constant value, but I personally think that for booleans
>    like need_check the "not" operator is ok.
>    So I will only highlight the !devargs :)

Make sense! Will send out a new version as per your above suggestions.

Thanks,
Jianfeng
diff mbox

Patch

diff --git a/lib/librte_eal/linuxapp/eal/eal_pci.c b/lib/librte_eal/linuxapp/eal/eal_pci.c
index b4dbf95..2b23d67 100644
--- a/lib/librte_eal/linuxapp/eal/eal_pci.c
+++ b/lib/librte_eal/linuxapp/eal/eal_pci.c
@@ -516,8 +516,26 @@  static inline int
 pci_one_device_bound_uio(void)
 {
 	struct rte_pci_device *dev = NULL;
+	struct rte_devargs *devargs;
+	int check_all = 1;
+	int need_check;
+
+	if (rte_pci_bus.bus.conf.scan_mode == RTE_BUS_SCAN_WHITELIST)
+		check_all = 0;
 
 	FOREACH_DEVICE_ON_PCIBUS(dev) {
+		devargs = dev->device.devargs;
+
+		need_check = 0;
+		if (check_all)
+			need_check = 1;
+		else if (devargs != NULL &&
+			 devargs->policy == RTE_DEV_WHITELISTED)
+			need_check = 1;
+
+		if (!need_check)
+			continue;
+
 		if (dev->kdrv == RTE_KDRV_IGB_UIO ||
 		   dev->kdrv == RTE_KDRV_UIO_GENERIC) {
 			return 1;