Commits
Vitaly Kuznetsov committed e72e7ac583e
drivers: hv: vmbus: Teardown synthetic interrupt controllers on module unload SynIC has to be switched off when we unload the module, otherwise registered memory pages can get corrupted after (as Hyper-V host still writes there) and we see the following crashes for random processes: [ 89.116774] BUG: Bad page map in process sh pte:4989c716 pmd:36f81067 [ 89.159454] addr:0000000000437000 vm_flags:00000875 anon_vma: (null) mapping:ffff88007bba55a0 index:37 [ 89.226146] vma->vm_ops->fault: filemap_fault+0x0/0x410 [ 89.257776] vma->vm_file->f_op->mmap: generic_file_mmap+0x0/0x60 [ 89.297570] CPU: 0 PID: 215 Comm: sh Tainted: G B 3.19.0-rc5_bug923184+ #488 [ 89.353738] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS 090006 05/23/2012 [ 89.409138] 0000000000000000 000000004e083d7b ffff880036e9fa18 ffffffff81a68d31 [ 89.468724] 0000000000000000 0000000000437000 ffff880036e9fa68 ffffffff811a1e3a [ 89.519233] 000000004989c716 0000000000000037 ffffea0001edc340 0000000000437000 [ 89.575751] Call Trace: [ 89.591060] [<ffffffff81a68d31>] dump_stack+0x45/0x57 [ 89.625164] [<ffffffff811a1e3a>] print_bad_pte+0x1aa/0x250 [ 89.667234] [<ffffffff811a2c95>] vm_normal_page+0x55/0xa0 [ 89.703818] [<ffffffff811a3105>] unmap_page_range+0x425/0x8a0 [ 89.737982] [<ffffffff811a3601>] unmap_single_vma+0x81/0xf0 [ 89.780385] [<ffffffff81184320>] ? lru_deactivate_fn+0x190/0x190 [ 89.820130] [<ffffffff811a4131>] unmap_vmas+0x51/0xa0 [ 89.860168] [<ffffffff811ad12c>] exit_mmap+0xac/0x1a0 [ 89.890588] [<ffffffff810763c3>] mmput+0x63/0x100 [ 89.919205] [<ffffffff811eba48>] flush_old_exec+0x3f8/0x8b0 [ 89.962135] [<ffffffff8123b5bb>] load_elf_binary+0x32b/0x1260 [ 89.998581] [<ffffffff811a14f2>] ? get_user_pages+0x52/0x60 hv_synic_cleanup() function exists but noone calls it now. Do the following: - call hv_synic_cleanup() on each cpu from vmbus_exit(); - write global disable bit through MSR; - use hv_synic_free_cpu() to avoid memory leask and code duplication. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>