David Howells d1698dc8a5 fscache: Fix the default for fscache_maybe_release_page() ... commit 9880150655 upstream. Fix the default for fscache_maybe_release_page() for when the cookie isn't valid or the page isn't cached. It mustn't return false as that indicates the page cannot yet be freed. The problem with the default is that if, say, there's no cache, but a network filesystem's pages are using up almost all the available memory, a system can OOM because the filesystem ->releasepage() op will not allow them to be released as fscache_maybe_release_page() incorrectly prevents it. This can be tested by writing a sequence of 512MiB files to an AFS mount. It does not affect NFS or CIFS because both of those wrap the call in a check of PG_fscache and it shouldn't bother Ceph as that only has PG_private set whilst writeback is in progress. This might be an issue for 9P, however. Note that the pages aren't entirely stuck. Removing a file or unmounting will clear things because that uses ->invalidatepage() instead. Fixes: 201a15428b ("FS-Cache: Handle pages pending storage that get evicted under OOM conditions") Reported-by: Marc Dionne <marc.dionne@auristor.com> Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Tested-by: Marc Dionne <marc.dionne@auristor.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2018-01-10 09:27:10 +01:00
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acpi
asm-generic	kaiser: cleanups while trying for gold link	2018-01-05 15:44:24 +01:00
clocksource
crypto	crypto: mcryptd - protect the per-CPU queue with a lock	2018-01-02 20:33:19 +01:00
drm	drm: extra printk() wrapper macros	2017-12-16 10:33:49 +01:00
dt-bindings	ARM: dts: Fix omap3 off mode pull defines	2017-11-21 09:21:19 +01:00
keys
kvm	KVM: arm/arm64: arch_timer: Preserve physical dist. active state on LR.active	2015-11-24 18:07:40 +01:00
linux	fscache: Fix the default for fscache_maybe_release_page()	2018-01-10 09:27:10 +01:00
math-emu
media	videobuf2-core: Check user space planes array in dqbuf	2016-05-04 14:48:50 -07:00
memory
misc
net	ipv4: igmp: guard against silly MTU values	2018-01-02 20:33:24 +01:00
pcmcia
ras
rdma	RDMA/core: Fix incorrect structure packing for booleans	2017-03-12 06:37:29 +01:00
rxrpc
scsi	scsi: libsas: align sata_device's rps_resp on a cacheline	2017-12-16 10:33:48 +01:00
soc	ARM: at91: define LPDDR types	2017-03-12 06:37:24 +01:00
sound	ALSA: seq: Avoid invalid lockdep class warning	2017-11-15 17:13:12 +01:00
target	target: fix ALUA transition timeout handling	2017-12-20 10:04:57 +01:00
trace	SUNRPC: Fix tracepoint storage issues with svc_recv and svc_rqst_status	2017-11-30 08:37:23 +00:00
uapi	USB: core: Add type-specific length check of BOS descriptors	2017-12-09 18:42:44 +01:00
video	drm/imx: Match imx-ipuv3-crtc components using device node in platform data	2016-06-07 18:14:37 -07:00
xen	fix xen_swiotlb_dma_mmap prototype	2017-10-05 09:41:48 +02:00
Kbuild