Commit d4263b12 authored Oct 14, 2020 by Aneesh Kumar K.V Committed by Michael Ellerman Oct 16, 2020

powerpc/opal_elog: Handle multiple writes to ack attribute



Even though we use self removing sysfs helper, we still need
to make sure we do the final kobject delete conditionally.
sysfs_remove_file_self() will handle parallel calls to remove
the sysfs attribute file and returns true only in the caller
that removed the attribute file. The other parallel callers
are returned false. Do the final kobject delete checking
the return value of sysfs_remove_file_self().

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Reviewed-by: Mahesh Salgaonkar <mahesh@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201014064813.109515-1-aneesh.kumar@linux.ibm.com

parent ffd0b25c

arch/powerpc/platforms/powernv/opal-elog.c

+8 −3

Original line number	Diff line number	Diff line
		@@ -72,9 +72,14 @@ static ssize_t elog_ack_store(struct elog_obj *elog_obj,
		const char *buf,
		size_t count)
		{
		/*
		* Try to self remove this attribute. If we are successful,
		* delete the kobject itself.
		*/
		if (sysfs_remove_file_self(&elog_obj->kobj, &attr->attr)) {
		opal_send_ack_elog(elog_obj->id);
		sysfs_remove_file_self(&elog_obj->kobj, &attr->attr);
		kobject_put(&elog_obj->kobj);
		}
		return count;
		}

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