On Mon, Jun 30, 2025 at 12:43:28PM +0500, Muhammad Usama Anjum wrote: > When there is memory pressure, at resume time dma_alloc_coherent() > returns error which in turn fails the loading of firmware and hence > the driver crashes: > > kernel: kworker/u33:5: page allocation failure: order:7, > mode:0xc04(GFP_NOIO|GFP_DMA32), nodemask=(null),cpuset=/,mems_allowed=0 > kernel: CPU: 1 UID: 0 PID: 7693 Comm: kworker/u33:5 Not tainted > 6.11.11-valve17-1-neptune-611-g027868a0ac03 #1 > 3843143b92e9da0fa2d3d5f21f51beaed15c7d59 Please don't wrap kernel log lines. > kernel: Hardware name: Valve Galileo/Galileo, BIOS F7G0112 08/01/2024 > kernel: Workqueue: mhi_hiprio_wq mhi_pm_st_worker [mhi] > kernel: Call Trace: > kernel: <TASK> > kernel: dump_stack_lvl+0x4e/0x70 > kernel: warn_alloc+0x164/0x190 > kernel: ? srso_return_thunk+0x5/0x5f > kernel: ? __alloc_pages_direct_compact+0xaf/0x360 > kernel: __alloc_pages_slowpath.constprop.0+0xc75/0xd70 > kernel: __alloc_pages_noprof+0x321/0x350 > kernel: __dma_direct_alloc_pages.isra.0+0x14a/0x290 > kernel: dma_direct_alloc+0x70/0x270 > kernel: mhi_fw_load_handler+0x126/0x340 [mhi > a96cb91daba500cc77f86bad60c1f332dc3babdf] > kernel: mhi_pm_st_worker+0x5e8/0xac0 [mhi > a96cb91daba500cc77f86bad60c1f332dc3babdf] Same here. > kernel: ? srso_return_thunk+0x5/0x5f > kernel: process_one_work+0x17e/0x330 > kernel: worker_thread+0x2ce/0x3f0 > kernel: ? __pfx_worker_thread+0x10/0x10 > kernel: kthread+0xd2/0x100 > kernel: ? __pfx_kthread+0x10/0x10 > kernel: ret_from_fork+0x34/0x50 > kernel: ? __pfx_kthread+0x10/0x10 > kernel: ret_from_fork_asm+0x1a/0x30 > kernel: </TASK> > kernel: Mem-Info: > kernel: active_anon:513809 inactive_anon:152 isolated_anon:0 > active_file:359315 inactive_file:2487001 isolated_file:0 > unevictable:637 dirty:19 writeback:0 > slab_reclaimable:160391 slab_unreclaimable:39729 > mapped:175836 shmem:51039 pagetables:4415 > sec_pagetables:0 bounce:0 > kernel_misc_reclaimable:0 > free:125666 free_pcp:0 free_cma:0 > > In above example, if we sum all the consumed memory, it comes out > to be 15.5GB and free memory is ~ 500MB from a total of 16GB RAM. > Even though memory is present. But all of the dma memory has been > exhausted or fragmented. > > Fix it by allocating it only once and then reuse the same allocated > memory. As we'll allocate this memory only once, this memory will stay > allocated. > > Tested-on: WCN6855 WLAN.HSP.1.1-03926.13-QCAHSPSWPL_V2_SILICONZ_CE-2.52297.6 > > Fixes: cd457afb1667 ("bus: mhi: core: Add support for downloading firmware over BHIe") No cc: stable? > Signed-off-by: Muhammad Usama Anjum <usama.anjum@xxxxxxxxxxxxx> > --- > Reported here: > https://lore.kernel.org/all/ead32f5b-730a-4b81-b38f-93d822f990c6@xxxxxxxxxxxxx > > Still a lot of more fixes are required. Hence, I'm not adding closes tag. > --- > drivers/bus/mhi/host/boot.c | 19 ++++++++++--------- > drivers/bus/mhi/host/init.c | 5 +++++ > drivers/bus/mhi/host/internal.h | 2 ++ > include/linux/mhi.h | 1 + > 4 files changed, 18 insertions(+), 9 deletions(-) > > diff --git a/drivers/bus/mhi/host/boot.c b/drivers/bus/mhi/host/boot.c > index b3a85aa3c4768..11bb8c12ac597 100644 > --- a/drivers/bus/mhi/host/boot.c > +++ b/drivers/bus/mhi/host/boot.c > @@ -302,8 +302,8 @@ static int mhi_fw_load_bhi(struct mhi_controller *mhi_cntrl, > return -EIO; > } > > -static void mhi_free_bhi_buffer(struct mhi_controller *mhi_cntrl, > - struct image_info *image_info) > +void mhi_free_bhi_buffer(struct mhi_controller *mhi_cntrl, > + struct image_info *image_info) > { > struct mhi_buf *mhi_buf = image_info->mhi_buf; > > @@ -455,18 +455,19 @@ static enum mhi_fw_load_type mhi_fw_load_type_get(const struct mhi_controller *m > > static int mhi_load_image_bhi(struct mhi_controller *mhi_cntrl, const u8 *fw_data, size_t size) > { > - struct image_info *image; > + struct image_info *image = mhi_cntrl->bhi_image; > int ret; > > - ret = mhi_alloc_bhi_buffer(mhi_cntrl, &image, size); > - if (ret) > - return ret; > + if (!image) { What prevents image from going away right after you tested it? thanks, greg k-h