Mohammed Shafi Shajakhan <mohammed@xxxxxxxxxxxxxxxx> wrote: > From: Mohammed Shafi Shajakhan <mohammed@xxxxxxxxxxxxxxxx> > > With maximum number of vap's configured in a two radio supported > systems of ~256 Mb RAM, doing a continuous wifi down/up and > intermittent traffic streaming from the connected stations results > in failure to allocate contiguous memory for tx buffers. This results > in the disappearance of all VAP's and a manual reboot is needed as > this is not a crash (or) OOM(for OOM killer to be invoked). To address > this allocate contiguous memory for tx buffers one time and re-use them > until the modules are unloaded but this results in a slight increase in > memory footprint of ath10k when the wifi is down, but the modules are > still loaded. Also as of now we use a separate bool 'tx_mem_allocated' > to keep track of the one time memory allocation, as we cannot come up > with something like 'ath10k_tx_{register,unregister}' before > 'ath10k_probe_fw' is called as 'ath10k_htt_tx_alloc_cont_frag_desc' > memory allocation is dependent on the hw_param 'continuous_frag_desc' > > a) memory footprint of ath10k without the change > > lsmod | grep ath10k > ath10k_core 414498 1 ath10k_pci > ath10k_pci 38236 0 > > b) memory footprint of ath10k with the change > > ath10k_core 414980 1 ath10k_pci > ath10k_pci 38236 0 > > Memory Failure Call trace: > > hostapd: page allocation failure: order:6, mode:0xd0 > [<c021f150>] (__dma_alloc_buffer.isra.23) from > [<c021f23c>] (__alloc_remap_buffer.isra.26+0x14/0xb8) > [<c021f23c>] (__alloc_remap_buffer.isra.26) from > [<c021f664>] (__dma_alloc+0x224/0x2b8) > [<c021f664>] (__dma_alloc) from [<c021f810>] > (arm_dma_alloc+0x84/0x90) > [<c021f810>] (arm_dma_alloc) from [<bf954764>] > (ath10k_htt_tx_alloc+0xe0/0x2e4 [ath10k_core]) > [<bf954764>] (ath10k_htt_tx_alloc [ath10k_core]) from > [<bf94e6ac>] (ath10k_core_start+0x538/0xcf8 [ath10k_core]) > [<bf94e6ac>] (ath10k_core_start [ath10k_core]) from > [<bf947eec>] (ath10k_start+0xbc/0x56c [ath10k_core]) > [<bf947eec>] (ath10k_start [ath10k_core]) from > [<bf8a7a04>] (drv_start+0x40/0x5c [mac80211]) > [<bf8a7a04>] (drv_start [mac80211]) from [<bf8b7cf8>] > (ieee80211_do_open+0x170/0x82c [mac80211]) > [<bf8b7cf8>] (ieee80211_do_open [mac80211]) from > [<c056afc8>] (__dev_open+0xa0/0xf4) > [21053.491752] Normal: 641*4kB (UEMR) 505*8kB (UEMR) 330*16kB (UEMR) > 126*32kB (UEMR) 762*64kB (UEMR) 237*128kB (UEMR) 1*256kB (M) 0*512kB > 0*1024kB 0*2048kB 0*4096kB = 95276kB > > Signed-off-by: Mohammed Shafi Shajakhan <mohammed@xxxxxxxxxxxxxxxx> Patch applied to ath-next branch of ath.git, thanks. 9ec34a86195a ath10k: fix Tx DMA alloc failure during continuous wifi down/up -- https://patchwork.kernel.org/patch/9453947/ Documentation about submitting wireless patches and checking status from patchwork: https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches