Mailing List Archive

PCI-Passthrough without "iommu=soft" possible?
Hi all,

When trying to boot a guest domain with 2 HBA's assigned via PCI-passthrough I
get a kernel-panic with 5.15.72.
If I add "iommu=soft" to the kernel command line it works, but locks up
quickly with messages like:
[Sun Oct 16 20:33:36 2022] mpt3sas 0000:81:00.0: swiotlb buffer is full (sz:
319488 bytes), total 32768 (slots), used 68 (slots)
[Sun Oct 16 20:33:36 2022] sd 0:0:26:0: scsi_dma_map failed: request for
708608 bytes!

in the logs (dmesg)

If I stay with 5.15.59 (without "iommu=soft", it is running stable, but I
would like to upgrade to newer kernels when possible.

I am currently running Xen 4.15.3

Is there an additional setting I need to add or any other options I haven't
been able to find through a few days of google-searches that are advised?

Many thanks,

Joost Roeleveld
Re: PCI-Passthrough without "iommu=soft" possible? [ In reply to ]
Hi Joost,

I'm very not a Xen expert but according to
https://wiki.xenproject.org/wiki/Linux_PVH which you gave in another mail,
your kernel needs to be decently recent and configured with the following:


CONFIG_HYPERVISOR_GUEST=y
CONFIG_PARAVIRT=y
CONFIG_PARAVIRT_GUEST=y
CONFIG_PARAVIRT_SPINLOCKS=y
CONFIG_XEN=y
CONFIG_XEN_PVHVM=y
CONFIG_XEN_PVH=y

As you did not mention anything about the kernels you were testing except
their version, as the one not working is the most recent, I'd suggest you
check in 5.15.72 if these options are configured or not.

Most kernels are configured to give access to its configuration through
/proc/config.gz, once the kernel is running on some system. A grep on that
file once uncompressed should answer that question.

Cheers,

mathias


Le mar. 18 oct. 2022 à 13:48, J. Roeleveld <joost@antarean.org> a écrit :

> Hi all,
>
> When trying to boot a guest domain with 2 HBA's assigned via
> PCI-passthrough I
> get a kernel-panic with 5.15.72.
> If I add "iommu=soft" to the kernel command line it works, but locks up
> quickly with messages like:
> [Sun Oct 16 20:33:36 2022] mpt3sas 0000:81:00.0: swiotlb buffer is full
> (sz:
> 319488 bytes), total 32768 (slots), used 68 (slots)
> [Sun Oct 16 20:33:36 2022] sd 0:0:26:0: scsi_dma_map failed: request for
> 708608 bytes!
>
> in the logs (dmesg)
>
> If I stay with 5.15.59 (without "iommu=soft", it is running stable, but I
> would like to upgrade to newer kernels when possible.
>
> I am currently running Xen 4.15.3
>
> Is there an additional setting I need to add or any other options I
> haven't
> been able to find through a few days of google-searches that are advised?
>
> Many thanks,
>
> Joost Roeleveld
>
>
>
>
Re: PCI-Passthrough without "iommu=soft" possible? [ In reply to ]
Hi Mathias,

The same wiki page lists that PCI passthrough is not possible using PVH. Unless that changed ?

--
Joost

Sent from Nine
________________________________
From: Mathias Dufresne [mathias.dufresne@gmail.com]
Sent: Tuesday, 18 October 2022 16:59
To: J. Roeleveld
Cc: [xen-users@lists.xenproject.org]
Subject: Re: PCI-Passthrough without "iommu=soft" possible?


Hi Joost,

I'm very not a Xen expert but according to
https://wiki.xenproject.org/wiki/Linux_PVH which you gave in another mail,
your kernel needs to be decently recent and configured with the following:


CONFIG_HYPERVISOR_GUEST=y
CONFIG_PARAVIRT=y
CONFIG_PARAVIRT_GUEST=y
CONFIG_PARAVIRT_SPINLOCKS=y
CONFIG_XEN=y
CONFIG_XEN_PVHVM=y
CONFIG_XEN_PVH=y

As you did not mention anything about the kernels you were testing except
their version, as the one not working is the most recent, I'd suggest you
check in 5.15.72 if these options are configured or not.

Most kernels are configured to give access to its configuration through
/proc/config.gz, once the kernel is running on some system. A grep on that
file once uncompressed should answer that question.

Cheers,

mathias


Le mar. 18 oct. 2022 à 13:48, J. Roeleveld joost@antarean.org a écrit :

> Hi all,
>
> When trying to boot a guest domain with 2 HBA's assigned via
> PCI-passthrough I
> get a kernel-panic with 5.15.72.
> If I add "iommu=soft" to the kernel command line it works, but locks up
> quickly with messages like:
> [Sun Oct 16 20:33:36 2022] mpt3sas 0000:81:00.0: swiotlb buffer is full
> (sz:
>319488 bytes), total 32768 (slots), used 68 (slots)
> [Sun Oct 16 20:33:36 2022] sd 0:0:26:0: scsi_dma_map failed: request for
>708608 bytes!
>
> in the logs (dmesg)
>
> If I stay with 5.15.59 (without "iommu=soft", it is running stable, but I
> would like to upgrade to newer kernels when possible.
>
> I am currently running Xen 4.15.3
>
> Is there an additional setting I need to add or any other options I
> haven't
> been able to find through a few days of google-searches that are advised?
>
> Many thanks,
>
> Joost Roeleveld
>
>
>
>
Re: PCI-Passthrough without "iommu=soft" possible? [ In reply to ]
Hi Joost,

No idea : )
Reading the first mail of this thread, I've understood that it worked using
older kernel (5.15.59) and that the very same configuration does not work
using the newer kernel. I just sent you some stuff to check what is the
difference between these two compiled kernels.

Cheers,

mathias

Le mar. 18 oct. 2022 à 17:13, Joost Roeleveld <joost@antarean.org> a écrit :

> Hi Mathias,
>
> The same wiki page lists that PCI passthrough is not possible using PVH.
> Unless that changed ?
>
> --
> Joost
>
> Sent from Nine <http://www.9folders.com/>
> ------------------------------
> *From:* Mathias Dufresne [mathias.dufresne@gmail.com]
> *Sent:* Tuesday, 18 October 2022 16:59
> *To:* J. Roeleveld
> *Cc:* [xen-users@lists.xenproject.org]
> *Subject:* Re: PCI-Passthrough without "iommu=soft" possible?
>
> Hi Joost,
>
> I'm very not a Xen expert but according to
> https://wiki.xenproject.org/wiki/Linux_PVH which you gave in another
> mail, your kernel needs to be decently recent and configured with the
> following:
>
>
> CONFIG_HYPERVISOR_GUEST=y
> CONFIG_PARAVIRT=y
> CONFIG_PARAVIRT_GUEST=y
> CONFIG_PARAVIRT_SPINLOCKS=y
> CONFIG_XEN=y
> CONFIG_XEN_PVHVM=y
> CONFIG_XEN_PVH=y
>
> As you did not mention anything about the kernels you were testing except
> their version, as the one not working is the most recent, I'd suggest you
> check in 5.15.72 if these options are configured or not.
>
> Most kernels are configured to give access to its configuration through
> /proc/config.gz, once the kernel is running on some system. A grep on that
> file once uncompressed should answer that question.
>
> Cheers,
>
> mathias
>
>
> Le mar. 18 oct. 2022 à 13:48, J. Roeleveld <joost@antarean.org> a écrit :
>
>> Hi all,
>>
>> When trying to boot a guest domain with 2 HBA's assigned via
>> PCI-passthrough I
>> get a kernel-panic with 5.15.72.
>> If I add "iommu=soft" to the kernel command line it works, but locks up
>> quickly with messages like:
>> [Sun Oct 16 20:33:36 2022] mpt3sas 0000:81:00.0: swiotlb buffer is full
>> (sz:
>> 319488 bytes), total 32768 (slots), used 68 (slots)
>> [Sun Oct 16 20:33:36 2022] sd 0:0:26:0: scsi_dma_map failed: request for
>> 708608 bytes!
>>
>> in the logs (dmesg)
>>
>> If I stay with 5.15.59 (without "iommu=soft", it is running stable, but I
>> would like to upgrade to newer kernels when possible.
>>
>> I am currently running Xen 4.15.3
>>
>> Is there an additional setting I need to add or any other options I
>> haven't
>> been able to find through a few days of google-searches that are advised?
>>
>> Many thanks,
>>
>> Joost Roeleveld
>>
>>
>>
>>
>
Re: PCI-Passthrough without "iommu=soft" possible? [ In reply to ]
Kernel config only changes when there are new options. I always use "make oldconfig" and check the prompts


Sent from Nine
________________________________
From: Mathias Dufresne [mathias.dufresne@gmail.com]
Sent: Tuesday, 18 October 2022 17:20
To: Joost Roeleveld
Cc: [xen-users@lists.xenproject.org]
Subject: Re: PCI-Passthrough without "iommu=soft" possible?


Hi Joost,

No idea : )
Reading the first mail of this thread, I've understood that it worked using
older kernel (5.15.59) and that the very same configuration does not work
using the newer kernel. I just sent you some stuff to check what is the
difference between these two compiled kernels.

Cheers,

mathias

Le mar. 18 oct. 2022 à 17:13, Joost Roeleveld joost@antarean.org a écrit :

> Hi Mathias,
>
> The same wiki page lists that PCI passthrough is not possible using PVH.
> Unless that changed ?
>
> --
> Joost
>
> Sent from Nine <http://www.9folders.com/>
> ------------------------------
> *From:* Mathias Dufresne [mathias.dufresne@gmail.com ]
> *Sent:* Tuesday, 18 October 2022 16:59
> *To:* J. Roeleveld
> *Cc:* [xen-users@lists.xenproject.org ]
> *Subject:* Re: PCI-Passthrough without "iommu=soft" possible?
>
> Hi Joost,
>
> I'm very not a Xen expert but according to
> https://wiki.xenproject.org/wiki/Linux_PVH which you gave in another
> mail, your kernel needs to be decently recent and configured with the
> following:
>
>
> CONFIG_HYPERVISOR_GUEST=y
> CONFIG_PARAVIRT=y
> CONFIG_PARAVIRT_GUEST=y
> CONFIG_PARAVIRT_SPINLOCKS=y
> CONFIG_XEN=y
> CONFIG_XEN_PVHVM=y
> CONFIG_XEN_PVH=y
>
> As you did not mention anything about the kernels you were testing except
> their version, as the one not working is the most recent, I'd suggest you
> check in 5.15.72 if these options are configured or not.
>
> Most kernels are configured to give access to its configuration through
> /proc/config.gz, once the kernel is running on some system. A grep on that
> file once uncompressed should answer that question.
>
> Cheers,
>
> mathias
>
>
> Le mar. 18 oct. 2022 à 13:48, J. Roeleveld joost@antarean.org a écrit :
>
>> Hi all,
>>
>> When trying to boot a guest domain with 2 HBA's assigned via
>> PCI-passthrough I
>> get a kernel-panic with 5.15.72.
>> If I add "iommu=soft" to the kernel command line it works, but locks up
>> quickly with messages like:
>> [Sun Oct 16 20:33:36 2022] mpt3sas 0000:81:00.0: swiotlb buffer is full
>> (sz:
>>319488 bytes), total 32768 (slots), used 68 (slots)
>> [Sun Oct 16 20:33:36 2022] sd 0:0:26:0: scsi_dma_map failed: request for
>>708608 bytes!
>>
>> in the logs (dmesg)
>>
>> If I stay with 5.15.59 (without "iommu=soft", it is running stable, but I
>> would like to upgrade to newer kernels when possible.
>>
>> I am currently running Xen 4.15.3
>>
>> Is there an additional setting I need to add or any other options I
>> haven't
>> been able to find through a few days of google-searches that are advised?
>>
>> Many thanks,
>>
>> Joost Roeleveld
>>
>>
>>
>>
>