drop broken 4.14 zram patch

diff --git a/queue-4.14/series b/queue-4.14/series
index 5d5747e0d2b635cba7f7595205d8cb29ab7702e8..5c7f25b2c8086eb03dbf9d09ccd55990a391d186 100644 (file)
--- a/queue-4.14/series
+++ b/queue-4.14/series
@@ -6,5 +6,4 @@ scsi-virtio_scsi-fix-io-hang-caused-by-automatic-irq-vector-affinity.patch
 kasan-add-no_sanitize-attribute-for-clang-builds.patch
 mark-hi-and-tasklet-softirq-synchronous.patch
 stop_machine-disable-preemption-after-queueing-stopper-threads.patch
-zram-remove-bd_cap_synchronous_io-with-writeback-feature.patch
 xen-netfront-don-t-cache-skb_shinfo.patch

diff --git a/queue-4.14/zram-remove-bd_cap_synchronous_io-with-writeback-feature.patch b/queue-4.14/zram-remove-bd_cap_synchronous_io-with-writeback-feature.patch
deleted file mode 100644 (file)
index ec87f4f..0000000
--- a/queue-4.14/zram-remove-bd_cap_synchronous_io-with-writeback-feature.patch
+++ /dev/null
@@ -1,108 +0,0 @@
-From 4f7a7beaee77275671654f7b9f3f9e73ca16ec65 Mon Sep 17 00:00:00 2001
-From: Minchan Kim <minchan@kernel.org>
-Date: Fri, 10 Aug 2018 17:23:10 -0700
-Subject: zram: remove BD_CAP_SYNCHRONOUS_IO with writeback feature
-
-From: Minchan Kim <minchan@kernel.org>
-
-commit 4f7a7beaee77275671654f7b9f3f9e73ca16ec65 upstream.
-
-If zram supports writeback feature, it's no longer a
-BD_CAP_SYNCHRONOUS_IO device beause zram does asynchronous IO operations
-for incompressible pages.
-
-Do not pretend to be synchronous IO device.  It makes the system very
-sluggish due to waiting for IO completion from upper layers.
-
-Furthermore, it causes a user-after-free problem because swap thinks the
-opearion is done when the IO functions returns so it can free the page
-(e.g., lock_page_or_retry and goto out_release in do_swap_page) but in
-fact, IO is asynchronous so the driver could access a just freed page
-afterward.
-
-This patch fixes the problem.
-
-  BUG: Bad page state in process qemu-system-x86  pfn:3dfab21
-  page:ffffdfb137eac840 count:0 mapcount:0 mapping:0000000000000000 index:0x1
-  flags: 0x17fffc000000008(uptodate)
-  raw: 017fffc000000008 dead000000000100 dead000000000200 0000000000000000
-  raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000
-  page dumped because: PAGE_FLAGS_CHECK_AT_PREP flag set
-  bad because of flags: 0x8(uptodate)
-  CPU: 4 PID: 1039 Comm: qemu-system-x86 Tainted: G    B 4.18.0-rc5+ #1
-  Hardware name: Supermicro Super Server/X10SRL-F, BIOS 2.0b 05/02/2017
-  Call Trace:
-    dump_stack+0x5c/0x7b
-    bad_page+0xba/0x120
-    get_page_from_freelist+0x1016/0x1250
-    __alloc_pages_nodemask+0xfa/0x250
-    alloc_pages_vma+0x7c/0x1c0
-    do_swap_page+0x347/0x920
-    __handle_mm_fault+0x7b4/0x1110
-    handle_mm_fault+0xfc/0x1f0
-    __get_user_pages+0x12f/0x690
-    get_user_pages_unlocked+0x148/0x1f0
-    __gfn_to_pfn_memslot+0xff/0x3c0 [kvm]
-    try_async_pf+0x87/0x230 [kvm]
-    tdp_page_fault+0x132/0x290 [kvm]
-    kvm_mmu_page_fault+0x74/0x570 [kvm]
-    kvm_arch_vcpu_ioctl_run+0x9b3/0x1990 [kvm]
-    kvm_vcpu_ioctl+0x388/0x5d0 [kvm]
-    do_vfs_ioctl+0xa2/0x630
-    ksys_ioctl+0x70/0x80
-    __x64_sys_ioctl+0x16/0x20
-    do_syscall_64+0x55/0x100
-    entry_SYSCALL_64_after_hwframe+0x44/0xa9
-
-Link: https://lore.kernel.org/lkml/0516ae2d-b0fd-92c5-aa92-112ba7bd32fc@contabo.de/
-Link: http://lkml.kernel.org/r/20180802051112.86174-1-minchan@kernel.org
-[minchan@kernel.org: fix changelog, add comment]
- Link: https://lore.kernel.org/lkml/0516ae2d-b0fd-92c5-aa92-112ba7bd32fc@contabo.de/
- Link: http://lkml.kernel.org/r/20180802051112.86174-1-minchan@kernel.org
- Link: http://lkml.kernel.org/r/20180805233722.217347-1-minchan@kernel.org
-[akpm@linux-foundation.org: coding-style fixes]
-Signed-off-by: Minchan Kim <minchan@kernel.org>
-Reported-by: Tino Lehnig <tino.lehnig@contabo.de>
-Tested-by: Tino Lehnig <tino.lehnig@contabo.de>
-Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
-Cc: Jens Axboe <axboe@kernel.dk>
-Cc: <stable@vger.kernel.org>   [4.15+]
-Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
-Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
----
- drivers/block/zram/zram_drv.c |   15 ++++++++++++++-
- 1 file changed, 14 insertions(+), 1 deletion(-)
-
---- a/drivers/block/zram/zram_drv.c
-+++ b/drivers/block/zram/zram_drv.c
-@@ -283,7 +283,8 @@ static void reset_bdev(struct zram *zram
-       zram->backing_dev = NULL;
-       zram->old_block_size = 0;
-       zram->bdev = NULL;
--
-+      zram->disk->queue->backing_dev_info->capabilities |=
-+                              BDI_CAP_SYNCHRONOUS_IO;
-       kvfree(zram->bitmap);
-       zram->bitmap = NULL;
- }
-@@ -385,6 +386,18 @@ static ssize_t backing_dev_store(struct
-       zram->backing_dev = backing_dev;
-       zram->bitmap = bitmap;
-       zram->nr_pages = nr_pages;
-+      /*
-+       * With writeback feature, zram does asynchronous IO so it's no longer
-+       * synchronous device so let's remove synchronous io flag. Othewise,
-+       * upper layer(e.g., swap) could wait IO completion rather than
-+       * (submit and return), which will cause system sluggish.
-+       * Furthermore, when the IO function returns(e.g., swap_readpage),
-+       * upper layer expects IO was done so it could deallocate the page
-+       * freely but in fact, IO is going on so finally could cause
-+       * use-after-free when the IO is really done.
-+       */
-+      zram->disk->queue->backing_dev_info->capabilities &=
-+                      ~BDI_CAP_SYNCHRONOUS_IO;
-       up_write(&zram->init_lock);
- 
-       pr_info("setup backing device %s\n", file_name);