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X-MS-Exchange-AntiSpam-MessageData: =?utf-8?B?elhpREVUS1NyMUZEQnJRVGVvT0FBNUZLSlRnd2RNSjV5ZW5GaGVrdWQvWG9t?= =?utf-8?B?aGU3WW5OREhUSGh5VVhUL2tSUWhXSzc4TzMyd0EzczdOZ1VoYmNXSVVCNGdG?= =?utf-8?B?SjJtNnQ2endKaHc4TExYTmpsU3J4Ri9GOHR2M2phU01EV1JKU3BWODZVVDh5?= =?utf-8?B?T1Q4N1l1emo4VG1tckNObEsza0Jwc0ZCL3lDemhpYWxoODNFS2RONW1oM1RE?= =?utf-8?B?blJVVEtmVmV0VmZYcE5kcnM2QjBYQ1RnTEJWY0tEdFd1MnBQS0M0UHEzRk1U?= =?utf-8?B?QVo0V3MwY20zR2JzeElUOGN2c0lwcjhKQ29NZHlFR09Wckc3QThYbVJ4cWxB?= =?utf-8?B?bHRyU25rbTl5QVRRUHluRTJYMkovc0RwVU93V2sxNWRmeVIzUDBVLzFQQ09w?= =?utf-8?B?VjYzWEtLRTQxUGdlS0pzdVFHd0hySkVVOExVVzhhMHkrdTIxdXA5alhSdEZR?= =?utf-8?B?ODBpVlAybXI1Qm1WMEJIblBnRTBlK0ZDTDVaamNGQWtMMW4wUjVsUnBhTUVr?= =?utf-8?B?c0lyZkdXeitOaCs1WUFhcGI2Ukk1ZVhRc2RnQTNWQkR6b1FncG9GSWlBOTls?= =?utf-8?B?YjNZUFJWSHZnKzNDMWN6aWR5em9JdktEYjg5SWtJRElXc2txcEJhTTJFV3Fw?= =?utf-8?B?UzVzNXVqQmFvMllzUlBkdGpHWEwvL0l5T1B2S01WYVkvS3lLUXZkaWZzNlpM?= =?utf-8?B?amRGQXpWZXJVa2pIOUlTZnZUY0txeFRqblUyYi9OK1A3MU1HNXJ5TVNreEJZ?= =?utf-8?B?emhCM1A5Wk1abHI3TmlKMVNKMUQ2S2RhUHhzaG9tYy9ZM1N6eTRtMk5XSzZI?= =?utf-8?B?TWdTUEFyUG1zaXRKVDR1UTBmUnhDeURHRjIzdnh3VkpPVEUwQVJRZFo5VXIw?= =?utf-8?B?QkhBYURZUnFjUUZHOUE1WjFWVlIrdDFvWU0xRU0xdnlFMVRWK29UNmErcSti?= =?utf-8?B?YXRIVXdNa0VMQmlpcXNnY0ZmNTVId2QzaTM0WWI0WUNGZHhQaVoxNEFtRTdU?= =?utf-8?B?VE1udllEQldxVHJiZk1RSFFCR1BaYXdHMTNScVh3VjVSalpMclh4ZGwvL1B2?= =?utf-8?B?ZEhqeGRURVdPTEtjT0V4bk9TUnRMWHE4eTEvUWtrcEZNTWNoV2phRTd3YlA1?= =?utf-8?B?aFNlWEE2SVdwVFpLcXQ1ZjVPODNtKzFZdmtPMGhpVkJlSk45SUYwRjF2c2Jm?= =?utf-8?B?UDhBSXNNb1g3bmpPNWxzanJyS3ZIZXhrRGlmYmVQVSt2Ky9lSmdUZy9UOW9y?= =?utf-8?B?QzQ5TzNqTThYamVRcXVaV2lOSTZGTEdOamR0V2dpTmlpS0cwa1JiSEtpY2lS?= =?utf-8?Q?wG2Awy1W0yUG+WIAEgaPdOu40dEpyaFILN?= X-MS-Exchange-CrossTenant-Network-Message-Id: 0d9fe86e-2153-4dab-5323-08d8bc61f596 X-MS-Exchange-CrossTenant-AuthSource: DS7PR03MB5608.namprd03.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 19 Jan 2021 10:06:59.3702 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 335836de-42ef-43a2-b145-348c2ee9ca5b X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: f8qqa/7EX7wQyTYcrPspb2by8JpoSuBv6VmbpZLyKsQ8aj/DNjxJ+Ki2szPywdVVfICW1UeCuGX+CkEzyWJx0Q== X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM6PR03MB3481 X-OriginatorOrg: citrix.com Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Tue, Jan 19, 2021 at 08:43:01AM +0100, Jürgen Groß wrote: > On 18.01.21 16:15, Roger Pau Monne wrote: > > Don't require the discard-alignment xenstore node to be present in > > order to correctly setup the feature. This can happen with versions of > > QEMU that only write the discard-granularity but not the > > discard-alignment node. > > > > Assume discard-alignment is 0 if not present. While there also fix the > > logic to not enable the discard feature if discard-granularity is not > > present. > > > > Reported-by: Arthur Borsboom > > Signed-off-by: Roger Pau Monné > > --- > > Cc: Boris Ostrovsky > > Cc: Juergen Gross > > Cc: Stefano Stabellini > > Cc: Konrad Rzeszutek Wilk > > Cc: "Roger Pau Monné" > > Cc: Jens Axboe > > Cc: xen-devel@lists.xenproject.org > > Cc: linux-block@vger.kernel.org > > Cc: Arthur Borsboom > > --- > > drivers/block/xen-blkfront.c | 25 +++++++++++++------------ > > 1 file changed, 13 insertions(+), 12 deletions(-) > > > > diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c > > index 5265975b3fba..5a93f7cc2939 100644 > > --- a/drivers/block/xen-blkfront.c > > +++ b/drivers/block/xen-blkfront.c > > @@ -2179,22 +2179,23 @@ static void blkfront_closing(struct blkfront_info *info) > > static void blkfront_setup_discard(struct blkfront_info *info) > > { > > - int err; > > - unsigned int discard_granularity; > > - unsigned int discard_alignment; > > + unsigned int discard_granularity = 0; > > + unsigned int discard_alignment = 0; > > + unsigned int discard_secure = 0; > > - info->feature_discard = 1; > > - err = xenbus_gather(XBT_NIL, info->xbdev->otherend, > > + xenbus_gather(XBT_NIL, info->xbdev->otherend, > > "discard-granularity", "%u", &discard_granularity, > > "discard-alignment", "%u", &discard_alignment, > > + "discard-secure", "%u", &discard_secure, > > NULL); > > This would mean that "discard-secure" will be evaluated only if the > other two items are set in Xenstore. From blkif.h I can't see this is > required, and your patch is modifying today's behavior in this regard. > > You might want to have three xenbus_read_unsigned() calls instead. You are right, discard-secure should be fetched regardless of whether discard-alignment exists. I can fetch discard-granularity and discard-alignment using xenbus_gather and keep discard-secure using xenbus_read_unsigned. Let me send a new version. Thanks, Roger.