Subject: Re: [PATCHv4 06/10] xen: Switch to using __pa_symbol
To: Laura Abbott <labbott@redhat.com>, Mark Rutland <mark.rutland@arm.com>,
        Ard Biesheuvel <ard.biesheuvel@linaro.org>,
        Will Deacon <will.deacon@arm.com>,
        Catalin Marinas <catalin.marinas@arm.com>,
        David Vrabel <david.vrabel@citrix.com>,
        Juergen Gross <jgross@suse.com>
References: <1480445729-27130-1-git-send-email-labbott@redhat.com>
 <1480445729-27130-7-git-send-email-labbott@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@redhat.com>,
        "H. Peter Anvin" <hpa@zytor.com>, x86@kernel.org,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        Andrew Morton <akpm@linux-foundation.org>,
        Marek Szyprowski <m.szyprowski@samsung.com>,
        Joonsoo Kim <iamjoonsoo.kim@lge.com>,
        linux-arm-kernel@lists.infradead.org, xen-devel@lists.xenproject.org
From: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Message-ID: <935fefbf-97dc-83fc-b7c3-ba3f19f2087f@oracle.com>
Date: Tue, 29 Nov 2016 17:26:18 -0500
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On 11/29/2016 01:55 PM, Laura Abbott wrote:
> __pa_symbol is the correct macro to use on kernel
> symbols. Switch to this from __pa.
>
> Signed-off-by: Laura Abbott <labbott@redhat.com>
> ---
> Found during a sweep of the kernel. Untested.
> ---
>  drivers/xen/xenbus/xenbus_dev_backend.c | 2 +-
>  drivers/xen/xenfs/xenstored.c           | 2 +-
>  2 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/xen/xenbus/xenbus_dev_backend.c b/drivers/xen/xenbus/xenbus_dev_backend.c
> index 4a41ac9..31ca2bf 100644
> --- a/drivers/xen/xenbus/xenbus_dev_backend.c
> +++ b/drivers/xen/xenbus/xenbus_dev_backend.c
> @@ -99,7 +99,7 @@ static int xenbus_backend_mmap(struct file *file, struct vm_area_struct *vma)
>  		return -EINVAL;
>  
>  	if (remap_pfn_range(vma, vma->vm_start,
> -			    virt_to_pfn(xen_store_interface),
> +			    PHYS_PFN(__pa_symbol(xen_store_interface)),
>  			    size, vma->vm_page_prot))
>  		return -EAGAIN;
>  
> diff --git a/drivers/xen/xenfs/xenstored.c b/drivers/xen/xenfs/xenstored.c
> index fef20db..21009ea 100644
> --- a/drivers/xen/xenfs/xenstored.c
> +++ b/drivers/xen/xenfs/xenstored.c
> @@ -38,7 +38,7 @@ static int xsd_kva_mmap(struct file *file, struct vm_area_struct *vma)
>  		return -EINVAL;
>  
>  	if (remap_pfn_range(vma, vma->vm_start,
> -			    virt_to_pfn(xen_store_interface),
> +			    PHYS_PFN(__pa_symbol(xen_store_interface)),
>  			    size, vma->vm_page_prot))
>  		return -EAGAIN;
>  


I suspect this won't work --- xen_store_interface doesn't point to a
kernel symbol.

-boris