Description

In the Linux kernel, the following vulnerability has been resolved: ath11k: fix the warning of dev_wake in mhi_pm_disable_transition() When test device recovery with below command, it has warning in message as below. echo assert > /sys/kernel/debug/ath11k/wcn6855\ hw2.0/simulate_fw_crash echo assert > /sys/kernel/debug/ath11k/qca6390\ hw2.0/simulate_fw_crash warning message: [ 1965.642121] ath11k_pci 0000:06:00.0: simulating firmware assert crash [ 1968.471364] ieee80211 phy0: Hardware restart was requested [ 1968.511305] ------------[ cut here ]------------ [ 1968.511368] WARNING: CPU: 3 PID: 1546 at drivers/bus/mhi/core/pm.c:505 mhi_pm_disable_transition+0xb37/0xda0 [mhi] [ 1968.511443] Modules linked in: ath11k_pci ath11k mac80211 libarc4 cfg80211 qmi_helpers qrtr_mhi mhi qrtr nvme nvme_core [ 1968.511563] CPU: 3 PID: 1546 Comm: kworker/u17:0 Kdump: loaded Tainted: G W 5.17.0-rc3-wt-ath+ #579 [ 1968.511629] Hardware name: Intel(R) Client Systems NUC8i7HVK/NUC8i7HVB, BIOS HNKBLi70.86A.0067.2021.0528.1339 05/28/2021 [ 1968.511704] Workqueue: mhi_hiprio_wq mhi_pm_st_worker [mhi] [ 1968.511787] RIP: 0010:mhi_pm_disable_transition+0xb37/0xda0 [mhi] [ 1968.511870] Code: a9 fe ff ff 4c 89 ff 44 89 04 24 e8 03 46 f6 e5 44 8b 04 24 41 83 f8 01 0f 84 21 fe ff ff e9 4c fd ff ff 0f 0b e9 af f8 ff ff <0f> 0b e9 5c f8 ff ff 48 89 df e8 da 9e ee e3 e9 12 fd ff ff 4c 89 [ 1968.511923] RSP: 0018:ffffc900024efbf0 EFLAGS: 00010286 [ 1968.511969] RAX: 00000000ffffffff RBX: ffff88811d241250 RCX: ffffffffc0176922 [ 1968.512014] RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff888118a90a24 [ 1968.512059] RBP: ffff888118a90800 R08: 0000000000000000 R09: ffff888118a90a27 [ 1968.512102] R10: ffffed1023152144 R11: 0000000000000001 R12: ffff888118a908ac [ 1968.512229] R13: ffff888118a90928 R14: dffffc0000000000 R15: ffff888118a90a24 [ 1968.512310] FS: 0000000000000000(0000) GS:ffff888234200000(0000) knlGS:0000000000000000 [ 1968.512405] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1968.512493] CR2: 00007f5538f443a8 CR3: 000000016dc28001 CR4: 00000000003706e0 [ 1968.512587] Call Trace: [ 1968.512672] <TASK> [ 1968.512751] ? _raw_spin_unlock_irq+0x1f/0x40 [ 1968.512859] mhi_pm_st_worker+0x3ac/0x790 [mhi] [ 1968.512959] ? mhi_pm_mission_mode_transition.isra.0+0x7d0/0x7d0 [mhi] [ 1968.513063] process_one_work+0x86a/0x1400 [ 1968.513184] ? pwq_dec_nr_in_flight+0x230/0x230 [ 1968.513312] ? move_linked_works+0x125/0x290 [ 1968.513416] worker_thread+0x6db/0xf60 [ 1968.513536] ? process_one_work+0x1400/0x1400 [ 1968.513627] kthread+0x241/0x2d0 [ 1968.513733] ? kthread_complete_and_exit+0x20/0x20 [ 1968.513821] ret_from_fork+0x22/0x30 [ 1968.513924] </TASK> Reason is mhi_deassert_dev_wake() from mhi_device_put() is called but mhi_assert_dev_wake() from __mhi_device_get_sync() is not called in progress of recovery. Commit 8e0559921f9a ("bus: mhi: core: Skip device wake in error or shutdown state") add check for the pm_state of mhi in __mhi_device_get_sync(), and the pm_state is not the normal state untill recovery is completed, so it leads the dev_wake is not 0 and above warning print in mhi_pm_disable_transition() while checking mhi_cntrl->dev_wake. Add check in ath11k_pci_write32()/ath11k_pci_read32() to skip call mhi_device_put() if mhi_device_get_sync() does not really do wake, then the warning gone. Tested-on: WCN6855 hw2.0 PCI WLAN.HSP.1.1-03003-QCAHSPSWPL_V1_V2_SILICONZ_LITE-2

Affected Products 2

References 3

• git.kernel.org https://git.kernel.org/stable/c/0d7a8a6204ea9271f1d0a8c66a9fd2f54d2e3cbc
  Patch
• git.kernel.org https://git.kernel.org/stable/c/5f18206cddae033c488e4879f198699092ca0524
  Patch
• git.kernel.org https://git.kernel.org/stable/c/a2d9b7357469949ad02f511fc69f8fa3a1afbf89
  Patch

Remediation

• git.kernel.org https://git.kernel.org/stable/c/0d7a8a6204ea9271f1d0a8c66a9fd2f54d2e3cbc
  Patch
• git.kernel.org https://git.kernel.org/stable/c/5f18206cddae033c488e4879f198699092ca0524
  Patch
• git.kernel.org https://git.kernel.org/stable/c/a2d9b7357469949ad02f511fc69f8fa3a1afbf89
  Patch