Skip to content

L
linux
Switch branch/tag
  1. 28 Feb, 2019 10 commits
  3. 27 Feb, 2019 5 commits
    • YueHaibing's avatar
      staging: rtl8723bs: Remove duplicated include from drv_types.h · 79e246fd
      YueHaibing authored 
      Remove duplicated include.
Signed-off-by: default avatarYueHaibing <yuehaibing@huawei.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      79e246fd
    • Madhumitha Prabakaran's avatar
      Staging: vt6655: Alignment should match open parenthesis · 73ad3e24
      Madhumitha Prabakaran authored 
      Fix the check to improve readibility
CHECK: Alignment should match open parenthesis
Signed-off-by: default avatarMadhumitha Prabakaran <madhumithabiw@gmail.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      73ad3e24
    • Gao Xiang's avatar
      staging: erofs: fix mis-acted TAIL merging behavior · a112152f
      Gao Xiang authored 
      EROFS has an optimized path called TAIL merging, which is designed
to merge multiple reads and the corresponding decompressions into
one if these requests read continuous pages almost at the same time.

In general, it behaves as follows:
 ________________________________________________________________
  ... |  TAIL  .  HEAD  |  PAGE  |  PAGE  |  TAIL    . HEAD | ...
 _____|_combined page A_|________|________|_combined page B_|____
        1  ]  ->  [  2                          ]  ->  [ 3
If the above three reads are requested in the order 1-2-3, it will
generate a large work chain rather than 3 individual work chains
to reduce scheduling overhead and boost up sequential read.

However, if Read 2 is processed slightly earlier than Read 1,
currently it still generates 2 individual work chains (chain 1, 2)
but it does in-place decompression for combined page A, moreover,
if chain 2 decompresses ahead of chain 1, it will be a race and
lead to corrupted decompressed page. This patch fixes it.

Fixes: 3883a79a ("staging: erofs: introduce VLE decompression support")
Cc: <stable@vger.kernel.org> # 4.19+
Signed-off-by: default avatarGao Xiang <gaoxiang25@huawei.com>
Reviewed-by: default avatarChao Yu <yuchao0@huawei.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      a112152f
    • Gao Xiang's avatar
      staging: erofs: fix illegal address access under memory pressure · 1e5ceeab
      Gao Xiang authored 
      Considering a read request with two decompressed file pages,
If a decompression work cannot be started on the previous page
due to memory pressure but in-memory LTP map lookup is done,
builder->work should be still NULL.

Moreover, if the current page also belongs to the same map,
it won't try to start the decompression work again and then
run into trouble.

This patch aims to solve the above issue only with little changes
as much as possible in order to make the fix backport easier.

kernel message is:
<4>[1051408f.015930s]SLUB: Unable to allocate memory on node -1, gfp=0x2408040(GFP_NOFS|__GFP_ZERO)
<4>[1051408f.015930s]  cache: erofs_compress, object size: 144, buffer size: 144, default order: 0, min order: 0
<4>[1051408f.015930s]  node 0: slabs: 98, objs: 2744, free: 0
  * Cannot allocate the decompression work

<3>[1051408f.015960s]erofs: z_erofs_vle_normalaccess_readpages, readahead error at page 1008 of nid 5391488
  * Note that the previous page was failed to read

<0>[1051408f.015960s]Internal error: Accessing user space memory outside uaccess.h routines: 96000005 [#1] PREEMPT SMP
...
<4>[1051408f.015991s]Hardware name: kirin710 (DT)
...
<4>[1051408f.016021s]PC is at z_erofs_vle_work_add_page+0xa0/0x17c
<4>[1051408f.016021s]LR is at z_erofs_do_read_page+0x12c/0xcf0
...
<4>[1051408f.018096s][<ffffff80c6fb0fd4>] z_erofs_vle_work_add_page+0xa0/0x17c
<4>[1051408f.018096s][<ffffff80c6fb3814>] z_erofs_vle_normalaccess_readpages+0x1a0/0x37c
<4>[1051408f.018096s][<ffffff80c6d670b8>] read_pages+0x70/0x190
<4>[1051408f.018127s][<ffffff80c6d6736c>] __do_page_cache_readahead+0x194/0x1a8
<4>[1051408f.018127s][<ffffff80c6d59318>] filemap_fault+0x398/0x684
<4>[1051408f.018127s][<ffffff80c6d8a9e0>] __do_fault+0x8c/0x138
<4>[1051408f.018127s][<ffffff80c6d8f90c>] handle_pte_fault+0x730/0xb7c
<4>[1051408f.018127s][<ffffff80c6d8fe04>] __handle_mm_fault+0xac/0xf4
<4>[1051408f.018157s][<ffffff80c6d8fec8>] handle_mm_fault+0x7c/0x118
<4>[1051408f.018157s][<ffffff80c8c52998>] do_page_fault+0x354/0x474
<4>[1051408f.018157s][<ffffff80c8c52af8>] do_translation_fault+0x40/0x48
<4>[1051408f.018157s][<ffffff80c6c002f4>] do_mem_abort+0x80/0x100
<4>[1051408f.018310s]---[ end trace 9f4009a3283bd78b ]---

Fixes: 3883a79a ("staging: erofs: introduce VLE decompression support")
Cc: <stable@vger.kernel.org> # 4.19+
Signed-off-by: default avatarGao Xiang <gaoxiang25@huawei.com>
Reviewed-by: default avatarChao Yu <yuchao0@huawei.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      1e5ceeab
    • Gao Xiang's avatar
      staging: erofs: compressed_pages should not be accessed again after freed · af692e11
      Gao Xiang authored 
      This patch resolves the following page use-after-free issue,
z_erofs_vle_unzip:
    ...
    for (i = 0; i < nr_pages; ++i) {
        ...
        z_erofs_onlinepage_endio(page);  (1)
    }

    for (i = 0; i < clusterpages; ++i) {
        page = compressed_pages[i];

        if (page->mapping == mngda)      (2)
            continue;
        /* recycle all individual staging pages */
        (void)z_erofs_gather_if_stagingpage(page_pool, page); (3)
        WRITE_ONCE(compressed_pages[i], NULL);
    }
    ...

After (1) is executed, page is freed and could be then reused, if
compressed_pages is scanned after that, it could fall info (2) or
(3) by mistake and that could finally be in a mess.

This patch aims to solve the above issue only with little changes
as much as possible in order to make the fix backport easier.

Fixes: 3883a79a ("staging: erofs: introduce VLE decompression support")
Cc: <stable@vger.kernel.org> # 4.19+
Signed-off-by: default avatarGao Xiang <gaoxiang25@huawei.com>
Reviewed-by: default avatarChao Yu <yuchao0@huawei.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      af692e11
  5. 26 Feb, 2019 25 commits
GitLab Nexedi Edition | About GitLab | About Nexedi | 沪ICP备2021021310号-2 | 沪ICP备2021021310号-7