[RESEND v2 1/4] target: core: fix preempt and abort for allreg res

[Dmitry Bogdanov <d.bogdanov@yadro.com>]

Match a key only if SARK is not zero according to SPC-4 and the comment
above the code:
 If an all registrants persistent reservation is present and the SERVICE
 ACTION RESERVATION KEY field is set to zero, then all registrations
 shall be removed except for that of the I_T nexus that is being used
 for the PERSISTENT RESERVE OUT command;

Without this patch in case of SARK==0 no registrants will be removed.

Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Dmitry Bogdanov <d.bogdanov@yadro.com>
---
v2:
  remove superfluous parentheses
---
 drivers/target/target_core_pr.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/target/target_core_pr.c b/drivers/target/target_core_pr.c
index a1d67554709f..1521a97ddac2 100644
--- a/drivers/target/target_core_pr.c
+++ b/drivers/target/target_core_pr.c
@@ -3022,7 +3022,7 @@ core_scsi3_pro_preempt(struct se_cmd *cmd, int type, int scope, u64 res_key,
 		if (calling_it_nexus)
 			continue;
 
-		if (pr_reg->pr_res_key != sa_res_key)
+		if (sa_res_key && pr_reg->pr_res_key != sa_res_key)
 			continue;
 
 		pr_reg_nacl = pr_reg->pr_reg_nacl;
-- 
2.25.1