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CVE-2024-36882: mm: use memalloc_nofs_save() in page_cache_ra_order()

Nico Pache requested to merge npache/centos-stream-9:RHEL-39635 into main 
mm: use memalloc_nofs_save() in page_cache_ra_order()
    
    commit 30153e4466647a17eebfced13eede5cbe4290e69
    Author: Kefeng Wang <wangkefeng.wang@huawei.com>
    Date:   Fri Apr 26 19:29:38 2024 +0800
    
        mm: use memalloc_nofs_save() in page_cache_ra_order()
    
        See commit f2c817bed58d ("mm: use memalloc_nofs_save in readahead path"),
        ensure that page_cache_ra_order() do not attempt to reclaim file-backed
        pages too, or it leads to a deadlock, found issue when test ext4 large
        folio.
    
         INFO: task DataXceiver for:7494 blocked for more than 120 seconds.
         "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
         task:DataXceiver for state:D stack:0     pid:7494  ppid:1      flags:0x00000200
         Call trace:
          __switch_to+0x14c/0x240
          __schedule+0x82c/0xdd0
          schedule+0x58/0xf0
          io_schedule+0x24/0xa0
          __folio_lock+0x130/0x300
          migrate_pages_batch+0x378/0x918
          migrate_pages+0x350/0x700
          compact_zone+0x63c/0xb38
          compact_zone_order+0xc0/0x118
          try_to_compact_pages+0xb0/0x280
          __alloc_pages_direct_compact+0x98/0x248
          __alloc_pages+0x510/0x1110
          alloc_pages+0x9c/0x130
          folio_alloc+0x20/0x78
          filemap_alloc_folio+0x8c/0x1b0
          page_cache_ra_order+0x174/0x308
          ondemand_readahead+0x1c8/0x2b8
          page_cache_async_ra+0x68/0xb8
          filemap_readahead.isra.0+0x64/0xa8
          filemap_get_pages+0x3fc/0x5b0
          filemap_splice_read+0xf4/0x280
          ext4_file_splice_read+0x2c/0x48 [ext4]
          vfs_splice_read.part.0+0xa8/0x118
          splice_direct_to_actor+0xbc/0x288
          do_splice_direct+0x9c/0x108
          do_sendfile+0x328/0x468
          __arm64_sys_sendfile64+0x8c/0x148
          invoke_syscall+0x4c/0x118
          el0_svc_common.constprop.0+0xc8/0xf0
          do_el0_svc+0x24/0x38
          el0_svc+0x4c/0x1f8
          el0t_64_sync_handler+0xc0/0xc8
          el0t_64_sync+0x188/0x190
    
        Link: https://lkml.kernel.org/r/20240426112938.124740-1-wangkefeng.wang@huawei.com
        Fixes: 793917d997df ("mm/readahead: Add large folio readahead")
        Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
        Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
        Cc: Zhang Yi <yi.zhang@huawei.com>
        Cc: <stable@vger.kernel.org>
        Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

CVE: CVE-2024-36882

JIRA: https://issues.redhat.com/browse/RHEL-39635

Signed-off-by: Nico Pache npache@redhat.com

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