Re: [PATCH v2] bus: mhi: host: don't free bhie tables during suspend/hibernation
From: Muhammad Usama Anjum
Date: Fri Apr 11 2025 - 14:34:34 EST
On 4/11/25 1:39 PM, Krishna Chaitanya Chundru wrote:
>
>
> On 4/11/2025 12:32 PM, Muhammad Usama Anjum wrote:
>> On 4/11/25 8:37 AM, Krishna Chaitanya Chundru wrote:
>>>
>>>
>>> On 4/10/2025 8:26 PM, Muhammad Usama Anjum wrote:
>>>> Fix dma_direct_alloc() failure at resume time during bhie_table
>>>> allocation. There is a crash report where at resume time, the memory
>>>> from the dma doesn't get allocated and MHI fails to re-initialize.
>>>> There may be fragmentation of some kind which fails the allocation
>>>> call.
>>>>
>>>> To fix it, don't free the memory at power down during suspend /
>>>> hibernation. Instead, use the same allocated memory again after every
>>>> resume / hibernation. This patch has been tested with resume and
>>>> hibernation both.
>>>>
>>>> The rddm is of constant size for a given hardware. While the fbc_image
>>>> size depends on the firmware. If the firmware changes, we'll free and
>>> If firmware image will change between suspend and resume ?
>> Yes, correct.
>>
> why the firmware image size will change between suspend & resume?
> who will update the firmware image after bootup?
> It is not expected behaviour.
I was trying to research if the firmware can change or not. I've not
found any documentation on it.
If the firmare is updated in filesystem before suspend/hibernate, would
the new firwmare be loaded the next time kernel resumes as the older
firmware is no where to be found?
What do you think about this?
>
> - Krishna chaitanya.
>>>> allocate new memory for it.
>>>>
>>>> Here are the crash logs:
>>>>
>>>> [ 3029.338587] mhi mhi0: Requested to power ON
>>>> [ 3029.338621] mhi mhi0: Power on setup success
>>>> [ 3029.668654] kworker/u33:8: page allocation failure: order:7,
>>>> mode:0xc04(GFP_NOIO|GFP_DMA32), nodemask=(null),cpuset=/,mems_allowed=0
>>>> [ 3029.668682] CPU: 4 UID: 0 PID: 2744 Comm: kworker/u33:8 Not tainted
>>>> 6.11.11-valve10-1-neptune-611-gb69e902b4338
>>>> #1ed779c892334112fb968aaa3facf9686b5ff0bd7
>>>> [ 3029.668690] Hardware name: Valve Galileo/Galileo, BIOS F7G0112
>>>> 08/01/2024
>>>> [ 3029.668694] Workqueue: mhi_hiprio_wq mhi_pm_st_worker [mhi]
>>>> [ 3029.668717] Call Trace:
>>>> [ 3029.668722] <TASK>
>>>> [ 3029.668728] dump_stack_lvl+0x4e/0x70
>>>> [ 3029.668738] warn_alloc+0x164/0x190
>>>> [ 3029.668747] ? srso_return_thunk+0x5/0x5f
>>>> [ 3029.668754] ? __alloc_pages_direct_compact+0xaf/0x360
>>>> [ 3029.668761] __alloc_pages_slowpath.constprop.0+0xc75/0xd70
>>>> [ 3029.668774] __alloc_pages_noprof+0x321/0x350
>>>> [ 3029.668782] __dma_direct_alloc_pages.isra.0+0x14a/0x290
>>>> [ 3029.668790] dma_direct_alloc+0x70/0x270
>>>> [ 3029.668796] mhi_alloc_bhie_table+0xe8/0x190 [mhi
>>>> faa917c5aa23a5f5b12d6a2c597067e16d2fedc0]
>>>> [ 3029.668814] mhi_fw_load_handler+0x1bc/0x310 [mhi
>>>> faa917c5aa23a5f5b12d6a2c597067e16d2fedc0]
>>>> [ 3029.668830] mhi_pm_st_worker+0x5c8/0xaa0 [mhi
>>>> faa917c5aa23a5f5b12d6a2c597067e16d2fedc0]
>>>> [ 3029.668844] ? srso_return_thunk+0x5/0x5f
>>>> [ 3029.668853] process_one_work+0x17e/0x330
>>>> [ 3029.668861] worker_thread+0x2ce/0x3f0
>>>> [ 3029.668868] ? __pfx_worker_thread+0x10/0x10
>>>> [ 3029.668873] kthread+0xd2/0x100
>>>> [ 3029.668879] ? __pfx_kthread+0x10/0x10
>>>> [ 3029.668885] ret_from_fork+0x34/0x50
>>>> [ 3029.668892] ? __pfx_kthread+0x10/0x10
>>>> [ 3029.668898] ret_from_fork_asm+0x1a/0x30
>>>> [ 3029.668910] </TASK>
>>>>
>>>> Tested-on: QCNFA765 WLAN.HSP.1.1-03926.13-
>>>> QCAHSPSWPL_V2_SILICONZ_CE-2.52297.6
>>>>
>>>> Signed-off-by: Muhammad Usama Anjum <usama.anjum@xxxxxxxxxxxxx>
>>>> ---
>>>> Changes sice v1:
>>>> - Don't free bhie tables during suspend/hibernation only
>>>> - Handle fbc_image changed size correctly
>>>> - Remove fbc_image getting set to NULL in *free_bhie_table()
>>>> ---
>>>> drivers/bus/mhi/host/boot.c | 15 +++++++++++----
>>>> drivers/bus/mhi/host/init.c | 13 ++++++++++---
>>>> drivers/net/wireless/ath/ath11k/mhi.c | 9 +++++----
>>>> include/linux/mhi.h | 7 +++++++
>>>> 4 files changed, 33 insertions(+), 11 deletions(-)
>>>>
>>>> diff --git a/drivers/bus/mhi/host/boot.c b/drivers/bus/mhi/host/boot.c
>>>> index 9dcc7184817d5..0df26100c8f9c 100644
>>>> --- a/drivers/bus/mhi/host/boot.c
>>>> +++ b/drivers/bus/mhi/host/boot.c
>>>> @@ -487,10 +487,17 @@ void mhi_fw_load_handler(struct mhi_controller
>>>> *mhi_cntrl)
>>>> * device transitioning into MHI READY state
>>>> */
>>>> if (mhi_cntrl->fbc_download) {
>>>> - ret = mhi_alloc_bhie_table(mhi_cntrl, &mhi_cntrl->fbc_image,
>>>> fw_sz);
>>>> - if (ret) {
>>>> - release_firmware(firmware);
>>>> - goto error_fw_load;
>>>> + if (mhi_cntrl->fbc_image && fw_sz != mhi_cntrl->prev_fw_sz) {
>>>> + mhi_free_bhie_table(mhi_cntrl, mhi_cntrl->fbc_image);
>>>> + mhi_cntrl->fbc_image = NULL;
>>>> + }
>>>> + if (!mhi_cntrl->fbc_image) {
>>>> + ret = mhi_alloc_bhie_table(mhi_cntrl, &mhi_cntrl-
>>>>> fbc_image, fw_sz);
>>>> + if (ret) {
>>>> + release_firmware(firmware);
>>>> + goto error_fw_load;
>>>> + }
>>>> + mhi_cntrl->prev_fw_sz = fw_sz;
>>>> }
>>>> /* Load the firmware into BHIE vec table */
>>>> diff --git a/drivers/bus/mhi/host/init.c b/drivers/bus/mhi/host/init.c
>>>> index a9b1f8beee7bc..09b946b86ac46 100644
>>>> --- a/drivers/bus/mhi/host/init.c
>>>> +++ b/drivers/bus/mhi/host/init.c
>>>> @@ -1173,8 +1173,9 @@ int mhi_prepare_for_power_up(struct
>>>> mhi_controller *mhi_cntrl)
>>>> /*
>>>> * Allocate RDDM table for debugging purpose if specified
>>>> */
>>>> - mhi_alloc_bhie_table(mhi_cntrl, &mhi_cntrl->rddm_image,
>>>> - mhi_cntrl->rddm_size);
>>>> + if (!mhi_cntrl->rddm_image)
>>>> + mhi_alloc_bhie_table(mhi_cntrl, &mhi_cntrl->rddm_image,
>>>> + mhi_cntrl->rddm_size);
>>>> if (mhi_cntrl->rddm_image) {
>>>> ret = mhi_rddm_prepare(mhi_cntrl,
>>>> mhi_cntrl->rddm_image);
>>>> @@ -1212,12 +1213,18 @@ void mhi_unprepare_after_power_down(struct
>>>> mhi_controller *mhi_cntrl)
>>>> mhi_cntrl->rddm_image = NULL;
>>>> }
>>>> + mhi_partial_unprepare_after_power_down(mhi_cntrl);
>>>> +}
>>>> +EXPORT_SYMBOL_GPL(mhi_unprepare_after_power_down);
>>>> +
>>>> +void mhi_partial_unprepare_after_power_down(struct mhi_controller
>>>> *mhi_cntrl)
>>>> +{
>>>> mhi_cntrl->bhi = NULL;
>>>> mhi_cntrl->bhie = NULL;
>>>> mhi_deinit_dev_ctxt(mhi_cntrl);
>>>> }
>>>> -EXPORT_SYMBOL_GPL(mhi_unprepare_after_power_down);
>>>> +EXPORT_SYMBOL_GPL(mhi_partial_unprepare_after_power_down);
>>>>
>>> Instead of adding new API you can free memory from the unregister
>>> controller also.
>>>
>>> - Krishna Chaitanya.
>>>> static void mhi_release_device(struct device *dev)
>>>> {
>>>> diff --git a/drivers/net/wireless/ath/ath11k/mhi.c b/drivers/net/
>>>> wireless/ath/ath11k/mhi.c
>>>> index acd76e9392d31..f77cec79b5b80 100644
>>>> --- a/drivers/net/wireless/ath/ath11k/mhi.c
>>>> +++ b/drivers/net/wireless/ath/ath11k/mhi.c
>>>> @@ -460,12 +460,13 @@ void ath11k_mhi_stop(struct ath11k_pci *ab_pci,
>>>> bool is_suspend)
>>>> * workaround, otherwise ath11k_core_resume() will timeout
>>>> * during resume.
>>>> */
>>>> - if (is_suspend)
>>>> + if (is_suspend) {
>>>> mhi_power_down_keep_dev(ab_pci->mhi_ctrl, true);
>>>> - else
>>>> + mhi_partial_unprepare_after_power_down(ab_pci->mhi_ctrl);
>>>> + } else {
>>>> mhi_power_down(ab_pci->mhi_ctrl, true);
>>>> -
>>>> - mhi_unprepare_after_power_down(ab_pci->mhi_ctrl);
>>>> + mhi_unprepare_after_power_down(ab_pci->mhi_ctrl);
>>>> + }
>>>> }
>>>> int ath11k_mhi_suspend(struct ath11k_pci *ab_pci)
>>>> diff --git a/include/linux/mhi.h b/include/linux/mhi.h
>>>> index 059dc94d20bb6..65a47c712b3a0 100644
>>>> --- a/include/linux/mhi.h
>>>> +++ b/include/linux/mhi.h
>>>> @@ -382,6 +382,7 @@ struct mhi_controller {
>>>> const char *fw_image;
>>>> const u8 *fw_data;
>>>> size_t fw_sz;
>>>> + size_t prev_fw_sz;
>>>> const char *edl_image;
>>>> size_t rddm_size;
>>>> size_t sbl_size;
>>>> @@ -662,6 +663,12 @@ void mhi_power_down_keep_dev(struct
>>>> mhi_controller *mhi_cntrl, bool graceful);
>>>> */
>>>> void mhi_unprepare_after_power_down(struct mhi_controller
>>>> *mhi_cntrl);
>>>> +/**
>>>> + * mhi_partial_unprepare_after_power_down - Free any allocated memory
>>>> after power down partially
>>>> + * @mhi_cntrl: MHI controller
>>>> + */
>>>> +void mhi_partial_unprepare_after_power_down(struct mhi_controller
>>>> *mhi_cntrl);
>>>> +
>>>> /**
>>>> * mhi_pm_suspend - Move MHI into a suspended state
>>>> * @mhi_cntrl: MHI controller
>>
>>
--
Regards,
Usama