Commit 358ab796 authored Oct 17, 2020 by Vasant Hegde Committed by Michael Ellerman Oct 19, 2020

powerpc/powernv/dump: 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: Vasant Hegde <hegdevasant@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201017164236.264713-1-hegdevasant@linux.vnet.ibm.com

parent 0a43ae3e

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

+8 −3

Original line number	Diff line number	Diff line
		@@ -88,9 +88,14 @@ static ssize_t dump_ack_store(struct dump_obj *dump_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(&dump_obj->kobj, &attr->attr)) {
		dump_send_ack(dump_obj->id);
		sysfs_remove_file_self(&dump_obj->kobj, &attr->attr);
		kobject_put(&dump_obj->kobj);
		}
		return count;
		}

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