Commit 4573240f0764 ("xen/xenbus: eliminate xenbus_grant_ring()")
introduced an error for initialization of multi-page rings.
Cc: [email protected]
Fixes: 4573240f0764 ("xen/xenbus: eliminate xenbus_grant_ring()")
Reported-by: Sander Eikelenboom <[email protected]>
Signed-off-by: Juergen Gross <[email protected]>
---
drivers/xen/xenbus/xenbus_client.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)
diff --git a/drivers/xen/xenbus/xenbus_client.c b/drivers/xen/xenbus/xenbus_client.c
index d5f3f763717e..caa5c5c32f8e 100644
--- a/drivers/xen/xenbus/xenbus_client.c
+++ b/drivers/xen/xenbus/xenbus_client.c
@@ -382,9 +382,10 @@ int xenbus_setup_ring(struct xenbus_device *dev, gfp_t gfp, void **vaddr,
unsigned long ring_size = nr_pages * XEN_PAGE_SIZE;
grant_ref_t gref_head;
unsigned int i;
+ void *addr;
int ret;
- *vaddr = alloc_pages_exact(ring_size, gfp | __GFP_ZERO);
+ addr = *vaddr = alloc_pages_exact(ring_size, gfp | __GFP_ZERO);
if (!*vaddr) {
ret = -ENOMEM;
goto err;
@@ -401,13 +402,15 @@ int xenbus_setup_ring(struct xenbus_device *dev, gfp_t gfp, void **vaddr,
unsigned long gfn;
if (is_vmalloc_addr(*vaddr))
- gfn = pfn_to_gfn(vmalloc_to_pfn(vaddr[i]));
+ gfn = pfn_to_gfn(vmalloc_to_pfn(addr));
else
- gfn = virt_to_gfn(vaddr[i]);
+ gfn = virt_to_gfn(addr);
grefs[i] = gnttab_claim_grant_reference(&gref_head);
gnttab_grant_foreign_access_ref(grefs[i], dev->otherend_id,
gfn, 0);
+
+ addr += PAGE_SIZE;
}
return 0;
--
2.35.3
On 15.09.22 17:31, Juergen Gross wrote:
Hello Juergen
> Commit 4573240f0764 ("xen/xenbus: eliminate xenbus_grant_ring()")
> introduced an error for initialization of multi-page rings.
>
> Cc: [email protected]
> Fixes: 4573240f0764 ("xen/xenbus: eliminate xenbus_grant_ring()")
> Reported-by: Sander Eikelenboom <[email protected]>
> Signed-off-by: Juergen Gross <[email protected]>
> ---
> drivers/xen/xenbus/xenbus_client.c | 9 ++++++---
> 1 file changed, 6 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/xen/xenbus/xenbus_client.c b/drivers/xen/xenbus/xenbus_client.c
> index d5f3f763717e..caa5c5c32f8e 100644
> --- a/drivers/xen/xenbus/xenbus_client.c
> +++ b/drivers/xen/xenbus/xenbus_client.c
> @@ -382,9 +382,10 @@ int xenbus_setup_ring(struct xenbus_device *dev, gfp_t gfp, void **vaddr,
> unsigned long ring_size = nr_pages * XEN_PAGE_SIZE;
> grant_ref_t gref_head;
> unsigned int i;
> + void *addr;
> int ret;
>
> - *vaddr = alloc_pages_exact(ring_size, gfp | __GFP_ZERO);
> + addr = *vaddr = alloc_pages_exact(ring_size, gfp | __GFP_ZERO);
> if (!*vaddr) {
> ret = -ENOMEM;
> goto err;
> @@ -401,13 +402,15 @@ int xenbus_setup_ring(struct xenbus_device *dev, gfp_t gfp, void **vaddr,
> unsigned long gfn;
>
> if (is_vmalloc_addr(*vaddr))
> - gfn = pfn_to_gfn(vmalloc_to_pfn(vaddr[i]));
> + gfn = pfn_to_gfn(vmalloc_to_pfn(addr));
> else
> - gfn = virt_to_gfn(vaddr[i]);
> + gfn = virt_to_gfn(addr);
>
> grefs[i] = gnttab_claim_grant_reference(&gref_head);
> gnttab_grant_foreign_access_ref(grefs[i], dev->otherend_id,
> gfn, 0);
> +
> + addr += PAGE_SIZE;
XEN_PAGE_SIZE?
Reviewed-by: Oleksandr Tyshchenko <[email protected]>
P.S.
I wondered why I didn't face the similar issue(s) as I used Linux
v6.0.0-rc1 and several PV drivers including PV block device.
The answer is that the single-page ring is being used for all of them in
my environment.
root@salvator-x-h3-4x2g-xt-domu:~# dmesg | grep xenbus_setup_ring
[ 0.332449] vdispl vdispl-0: 0 xenbus_setup_ring: 1 pages
[ 0.333464] vdispl vdispl-0: 0 xenbus_setup_ring: 1 pages
[ 0.341350] vbd vbd-51713: 0 xenbus_setup_ring: 1 pages
[ 0.342750] vbd vbd-51713: 0 xenbus_setup_ring: 1 pages
[ 0.343261] vbd vbd-51713: 0 xenbus_setup_ring: 1 pages
[ 0.343798] vbd vbd-51713: 0 xenbus_setup_ring: 1 pages
[ 0.392969] vif vif-0: 0 xenbus_setup_ring: 1 pages
[ 0.518733] vif vif-0: 0 xenbus_setup_ring: 1 pages
[ 0.519198] vif vif-0: 0 xenbus_setup_ring: 1 pages
[ 0.519501] vif vif-0: 0 xenbus_setup_ring: 1 pages
[ 0.519948] vif vif-0: 0 xenbus_setup_ring: 1 pages
[ 0.520371] vif vif-0: 0 xenbus_setup_ring: 1 pages
[ 0.520805] vif vif-0: 0 xenbus_setup_ring: 1 pages
[ 0.521070] vif vif-0: 0 xenbus_setup_ring: 1 pages
[ 0.575451] vsnd vsnd-0: 0 xenbus_setup_ring: 1 pages
[ 0.576855] vsnd vsnd-0: 0 xenbus_setup_ring: 1 pages
> }
>
> return 0;
--
Regards,
Oleksandr Tyshchenko
On 15.09.2022 16:31, Juergen Gross wrote:
> Commit 4573240f0764 ("xen/xenbus: eliminate xenbus_grant_ring()")
> introduced an error for initialization of multi-page rings.
>
> Cc: [email protected]
> Fixes: 4573240f0764 ("xen/xenbus: eliminate xenbus_grant_ring()")
> Reported-by: Sander Eikelenboom <[email protected]>
> Signed-off-by: Juergen Gross <[email protected]>
Reviewed-by: Jan Beulich <[email protected]>
On 15.09.22 16:47, Oleksandr Tyshchenko wrote:
>
> On 15.09.22 17:31, Juergen Gross wrote:
>
> Hello Juergen
>
>> Commit 4573240f0764 ("xen/xenbus: eliminate xenbus_grant_ring()")
>> introduced an error for initialization of multi-page rings.
>>
>> Cc: [email protected]
>> Fixes: 4573240f0764 ("xen/xenbus: eliminate xenbus_grant_ring()")
>> Reported-by: Sander Eikelenboom <[email protected]>
>> Signed-off-by: Juergen Gross <[email protected]>
>> ---
>> drivers/xen/xenbus/xenbus_client.c | 9 ++++++---
>> 1 file changed, 6 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/xen/xenbus/xenbus_client.c b/drivers/xen/xenbus/xenbus_client.c
>> index d5f3f763717e..caa5c5c32f8e 100644
>> --- a/drivers/xen/xenbus/xenbus_client.c
>> +++ b/drivers/xen/xenbus/xenbus_client.c
>> @@ -382,9 +382,10 @@ int xenbus_setup_ring(struct xenbus_device *dev, gfp_t gfp, void **vaddr,
>> unsigned long ring_size = nr_pages * XEN_PAGE_SIZE;
>> grant_ref_t gref_head;
>> unsigned int i;
>> + void *addr;
>> int ret;
>>
>> - *vaddr = alloc_pages_exact(ring_size, gfp | __GFP_ZERO);
>> + addr = *vaddr = alloc_pages_exact(ring_size, gfp | __GFP_ZERO);
>> if (!*vaddr) {
>> ret = -ENOMEM;
>> goto err;
>> @@ -401,13 +402,15 @@ int xenbus_setup_ring(struct xenbus_device *dev, gfp_t gfp, void **vaddr,
>> unsigned long gfn;
>>
>> if (is_vmalloc_addr(*vaddr))
>> - gfn = pfn_to_gfn(vmalloc_to_pfn(vaddr[i]));
>> + gfn = pfn_to_gfn(vmalloc_to_pfn(addr));
>> else
>> - gfn = virt_to_gfn(vaddr[i]);
>> + gfn = virt_to_gfn(addr);
>>
>> grefs[i] = gnttab_claim_grant_reference(&gref_head);
>> gnttab_grant_foreign_access_ref(grefs[i], dev->otherend_id,
>> gfn, 0);
>> +
>> + addr += PAGE_SIZE;
>
> XEN_PAGE_SIZE?
Oh, indeed! Will change on commit.
>
>
> Reviewed-by: Oleksandr Tyshchenko <[email protected]>
Thanks,
Juergen