• Jeffy Chen's avatar
    drm/rockchip: Fix suspend crash when drm is not bound · 0fa375e6
    Jeffy Chen authored
    Currently we are allocating drm_device in rockchip_drm_bind, so if the
    suspend/resume code access it when drm is not bound, we would hit this
    crash:
    
    [  253.402836] Unable to handle kernel NULL pointer dereference at virtual address 00000028
    [  253.402837] pgd = ffffffc06c9b0000
    [  253.402841] [00000028] *pgd=0000000000000000, *pud=0000000000000000
    [  253.402844] Internal error: Oops: 96000005 [#1] PREEMPT SMP
    [  253.402859] Modules linked in: btusb btrtl btbcm btintel bluetooth ath10k_pci ath10k_core ar10k_ath ar10k_mac80211 cfg80211 ip6table_filter asix usbnet mii
    [  253.402864] CPU: 4 PID: 1331 Comm: cat Not tainted 4.4.70 #15
    [  253.402865] Hardware name: Google Scarlet (DT)
    [  253.402867] task: ffffffc076c0ce00 ti: ffffffc06c2c8000 task.ti: ffffffc06c2c8000
    [  253.402871] PC is at rockchip_drm_sys_suspend+0x20/0x5c
    
    Add sanity checks to prevent that.
    Reported-by: default avatarBrian Norris <briannorris@chromium.com>
    Signed-off-by: default avatarJeffy Chen <jeffy.chen@rock-chips.com>
    Signed-off-by: default avatarSean Paul <seanpaul@chromium.org>
    Link: https://patchwork.kernel.org/patch/9890297/
    0fa375e6
rockchip_drm_drv.c 11.9 KB