[dpdk-dev] [PATCH v4] VFIO: Avoid to enable vfio while the module not loaded
Qiu, Michael
michael.qiu at intel.com
Mon Dec 8 16:28:02 CET 2014
On 2014/12/8 20:19, Burakov, Anatoly wrote:
>> When vfio module is not loaded when kernel support vfio feature, the
>> routine still try to open the container to get file description.
>>
>> This action is not safe, and of cause got error messages:
>>
>> EAL: Detected 40 lcore(s)
>> EAL: unsupported IOMMU type!
>> EAL: VFIO support could not be initialized
>> EAL: Setting up memory...
>>
>> This may make user confuse, this patch make it reasonable and much more
>> soomth to user.
>>
>> Signed-off-by: Michael Qiu <michael.qiu at intel.com>
>> ---
>> v4 --> v3:
>> 1. Remove RTE_LOG for params check
>> 2. Remove "vfio" module check as "vfio_iommu_type1"
>> loaded indecated "vfio" loaded
>>
>> v3 --> v2:
>> 1. Add error log in rte_eal_check_module()
>> 2. Some code clean up.
>>
>> v2 --> v1:
>> 1. Move check_module() from rte_common.h to eal_private.h
>> and rename to rte_eal_check_module().
>> To make it linuxapp only.
>> 2. Some code clean up.
>>
>> lib/librte_eal/common/eal_private.h | 42
>> ++++++++++++++++++++++++++++++
>> lib/librte_eal/linuxapp/eal/eal_pci_vfio.c | 29 ++++++++++++++++++---
>> 2 files changed, 68 insertions(+), 3 deletions(-)
>>
>> diff --git a/lib/librte_eal/common/eal_private.h
>> b/lib/librte_eal/common/eal_private.h
>> index 232fcec..e877a25 100644
>> --- a/lib/librte_eal/common/eal_private.h
>> +++ b/lib/librte_eal/common/eal_private.h
>> @@ -35,6 +35,9 @@
>> #define _EAL_PRIVATE_H_
>>
>> #include <stdio.h>
>> +#include <string.h>
>> +#include <rte_log.h>
>> +#include <errno.h>
>>
>> /**
>> * Initialize the memzone subsystem (private to eal).
>> @@ -203,4 +206,43 @@ int rte_eal_alarm_init(void);
>> */
>> int rte_eal_dev_init(void);
>>
>> +/**
>> + * Function is to check if the kernel module(like, vfio,
>> +vfio_iommu_type1,
>> + * etc.) loaded.
>> + *
>> + * @param module_name
>> + * The module's name which need to be checked
>> + *
>> + * @return
>> + * -1 means some error happens(NULL pointer or open failure)
>> + * 0 means the module not loaded
>> + * 1 means the module loaded
>> + */
>> +static inline int
>> +rte_eal_check_module(const char *module_name) {
>> + char mod_name[30]; /* Any module names can be longer than 30
>> bytes? */
>> + int ret = 0;
>> +
>> + if (NULL == module_name)
>> + return -1;
>> +
>> + FILE * fd = fopen("/proc/modules", "r");
>> + if (NULL == fd) {
>> + RTE_LOG(ERR, EAL, "Open /proc/modules failed!"
>> + " error %i (%s)\n", errno, strerror(errno));
>> + return -1;
>> + }
>> + while(!feof(fd)) {
>> + fscanf(fd, "%s %*[^\n]", mod_name);
>> + if(!strcmp(mod_name, module_name)) {
>> + ret = 1;
>> + break;
>> + }
>> + }
>> + fclose(fd);
>> +
>> + return ret;
>> +}
>> +
> Apologies for not bringing this up before, but do we really want the rte_eal_check_module inline in the header? I think it would be better to declare it in eal_private but move the definition into eal.c.
No need, actually, I'm very appreciate that you can spend your time to
review my patch again and again. I really want to say thank you to you.
For rte_eal_check_module inline in the header, it really no need stay in
header, so ugly. I will make new version of it, and re-post.
>> #endif /* _EAL_PRIVATE_H_ */
>> diff --git a/lib/librte_eal/linuxapp/eal/eal_pci_vfio.c
>> b/lib/librte_eal/linuxapp/eal/eal_pci_vfio.c
>> index c1246e8..8c54d2a 100644
>> --- a/lib/librte_eal/linuxapp/eal/eal_pci_vfio.c
>> +++ b/lib/librte_eal/linuxapp/eal/eal_pci_vfio.c
>> @@ -44,6 +44,7 @@
>> #include <rte_tailq.h>
>> #include <rte_eal_memconfig.h>
>> #include <rte_malloc.h>
>> +#include <eal_private.h>
>>
>> #include "eal_filesystem.h"
>> #include "eal_pci_init.h"
>> @@ -339,10 +340,15 @@ pci_vfio_get_container_fd(void)
>> ret = ioctl(vfio_container_fd, VFIO_CHECK_EXTENSION,
>> VFIO_TYPE1_IOMMU);
>> if (ret != 1) {
>> if (ret < 0)
>> - RTE_LOG(ERR, EAL, " could not get IOMMU
>> type, "
>> - "error %i (%s)\n", errno,
>> strerror(errno));
>> + RTE_LOG(ERR, EAL, " could not get IOMMU
>> type,"
>> + " error %i (%s)\n", errno,
>> + strerror(errno));
>> else
>> - RTE_LOG(ERR, EAL, " unsupported IOMMU
>> type!\n");
>> + /* Better to show the IOMMU type return
>> from
>> + * kernel for easy debug
>> + */
>> + RTE_LOG(ERR, EAL, " unsupported IOMMU
>> type"
>> + " detected: %d in VFIO\n", ret);
> I'm not sure this message is meaningful. That ioctl call can either -1, 0 or 1. We already handle 1 separately; -1 means an error; 0 means IOMMU type 1 is not supported. The return value will *not* indicate which IOMMU types *are* currently supported - it will only indicate that the IOMMU type you requested is not supported. So there's really no point in indicating the return value in case of ret 0 - it is best to just mention that requested IOMMU type support is not enabled in VFIO.
Yes, you are right, I make a mistake.
>
>> close(vfio_container_fd);
>> return -1;
>> }
>> @@ -783,11 +789,28 @@ pci_vfio_enable(void) {
>> /* initialize group list */
>> int i;
>> + int module_vfio_type1;
>>
>> for (i = 0; i < VFIO_MAX_GROUPS; i++) {
>> vfio_cfg.vfio_groups[i].fd = -1;
>> vfio_cfg.vfio_groups[i].group_no = -1;
>> }
>> +
>> + module_vfio_type1 = rte_eal_check_module("vfio_iommu_type1");
>> +
>> + /* return error directly */
>> + if (module_vfio_type1 == -1) {
>> + RTE_LOG(INFO, EAL, "Could not get loaded module
>> details!\n");
>> + return -1;
>> + }
>> +
>> + /* return 0 if VFIO modules not loaded */
>> + if (module_vfio_type1 == 0) {
>> + RTE_LOG(INFO, EAL, "VFIO modules not all loaded,"
>> + " skip VFIO support ...\n");
>> + return 0;
>> + }
>> +
>> vfio_cfg.vfio_container_fd = pci_vfio_get_container_fd();
>>
>> /* check if we have VFIO driver enabled */
>> --
>> 1.9.3
>
More information about the dev
mailing list