Currently the NAPI processing loops through all
the copy engines and processes a particular copy
engine is the copy completion is set for that copy
engine. The host driver is not supposed to access
any copy engine register after clearing the interrupt
status register.
This might result in kernel crash like the one below
[ 1159.220143] Call trace:
[ 1159.220170] ath10k_snoc_read32+0x20/0x40 [ath10k_snoc]
[ 1159.220193] ath10k_ce_per_engine_service_any+0x78/0x130 [ath10k_core]
[ 1159.220203] ath10k_snoc_napi_poll+0x38/0x8c [ath10k_snoc]
[ 1159.220270] net_rx_action+0x100/0x3b0
[ 1159.220312] __do_softirq+0x164/0x30c
[ 1159.220345] run_ksoftirqd+0x2c/0x64
[ 1159.220380] smpboot_thread_fn+0x1b0/0x288
[ 1159.220405] kthread+0x11c/0x12c
[ 1159.220423] ret_from_fork+0x10/0x18
To avoid such a scenario, we generate an interrupt
summary by reading the copy completion for all the
copy engine before actually processing any of them.
This will avoid reading the interrupt status register
for any CE after the interrupt status is cleared.
Tested-on: WCN3990 hw1.0 SNOC WLAN.HL.3.1-01040-QCAHLSWMTPLZ-1
Signed-off-by: Rakesh Pillai <pillair@codeaurora.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/1593193967-29897-1-git-send-email-pillair@codeaurora.org
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