Re: [PATCH 2/2] IB/rdmavt: don't use rdmavt for UML

[Leon Romanovsky]

On Wed, Nov 30, 2022 at 12:09:58PM -0800, Randy Dunlap wrote:
> When building rdmavt for ARCH=um, qp.c has a build error on a reference
> to the x86-specific cpuinfo field 'x86_cache_size'.
> 
> Fix the build errors by making this driver depend on !UML.
> 
> Prevents these build errors:
> 
> ../drivers/infiniband/sw/rdmavt/qp.c: In function ‘rvt_wss_llc_size’:
> ../drivers/infiniband/sw/rdmavt/qp.c:88:29: error: ‘struct cpuinfo_um’ has no member named ‘x86_cache_size’
>    88 |         return boot_cpu_data.x86_cache_size;
> ../drivers/infiniband/sw/rdmavt/qp.c: In function ‘cacheless_memcpy’:
> ../drivers/infiniband/sw/rdmavt/qp.c:100:9: error: implicit declaration of function ‘__copy_user_nocache’; did you mean ‘copy_user_page’? [-Werror=implicit-function-declaration]
>   100 |         __copy_user_nocache(dst, (void __user *)src, n, 0);
> ../drivers/infiniband/sw/rdmavt/qp.c: In function ‘rvt_wss_llc_size’:
> ../drivers/infiniband/sw/rdmavt/qp.c:89:1: error: control reaches end of non-void function [-Werror=return-type]
>    89 | }
> 
> Fixes: 68f5d3f3b654 ("um: add PCI over virtio emulation driver")
> Signed-off-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
> Cc: Jason Gunthorpe <jgg@xxxxxxxxxx>
> Cc: Leon Romanovsky <leon@xxxxxxxxxx>
> Cc: Dennis Dalessandro <dennis.dalessandro@xxxxxxxxxxxxxxxxxxxx>
> Cc: linux-rdma@xxxxxxxxxxxxxxx
> Cc: Jeff Dike <jdike@xxxxxxxxxxx>
> Cc: Richard Weinberger <richard@xxxxxx>
> Cc: Anton Ivanov <anton.ivanov@xxxxxxxxxxxxxxxxxx>
> Cc: Johannes Berg <johannes@xxxxxxxxxxxxxxxx>
> Cc: linux-um@xxxxxxxxxxxxxxxxxxx
> ---
> v2: rebase & resend
> 
>  drivers/infiniband/sw/rdmavt/Kconfig |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff -- a/drivers/infiniband/sw/rdmavt/Kconfig b/drivers/infiniband/sw/rdmavt/Kconfig
> --- a/drivers/infiniband/sw/rdmavt/Kconfig
> +++ b/drivers/infiniband/sw/rdmavt/Kconfig
> @@ -2,7 +2,7 @@
>  config INFINIBAND_RDMAVT
>  	tristate "RDMA verbs transport library"
>  	depends on INFINIBAND_VIRT_DMA
> -	depends on X86_64
> +	depends on X86_64 && !UML

Same comment as for patch #1.

>  	depends on PCI
>  	help
>  	This is a common software verbs provider for RDMA networks.