From: Gao Xiang <hsiangkao@redhat.com>
Date: Thu, 22 Oct 2020 14:57:21 +0000 (+0800)
Subject: erofs: fix setting up pcluster for temporary pages
X-Git-Tag: v5.9.9~73
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=877c8cb029a582bdafa1ddbaeeeab5c6e67a5f79;p=thirdparty%2Fkernel%2Fstable.git

erofs: fix setting up pcluster for temporary pages

commit a30573b3cdc77b8533d004ece1ea7c0146b437a0 upstream.

pcluster should be only set up for all managed pages instead of
temporary pages. Since it currently uses page->mapping to identify,
the impact is minor for now.

[ Update: Vladimir reported the kernel log becomes polluted
  because PAGE_FLAGS_CHECK_AT_FREE flag(s) set if the page
  allocation debug option is enabled. ]

Link: https://lore.kernel.org/r/20201022145724.27284-1-hsiangkao@aol.com
Fixes: 5ddcee1f3a1c ("erofs: get rid of __stagingpage_alloc helper")
Cc: <stable@vger.kernel.org> # 5.5+
Tested-by: Vladimir Zapolskiy <vladimir@tuxera.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Gao Xiang <hsiangkao@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/fs/erofs/zdata.c b/fs/erofs/zdata.c
index 6c939def00f95..118d9fe02c4e2 100644
--- a/fs/erofs/zdata.c
+++ b/fs/erofs/zdata.c
@@ -1080,8 +1080,11 @@ out_allocpage:
 		cond_resched();
 		goto repeat;
 	}
-	set_page_private(page, (unsigned long)pcl);
-	SetPagePrivate(page);
+
+	if (tocache) {
+		set_page_private(page, (unsigned long)pcl);
+		SetPagePrivate(page);
+	}
 out:	/* the only exit (for tracing and debugging) */
 	return page;
 }