On Tue, Jul 06, 2021 at 09:26:59AM +0000, Yassine Oudjana wrote: > In-Reply-To: <20210527124356.22367-1-will@xxxxxxxxxx> > > Reduce ARCH_DMA_MINALIGN to 64 bytes and allow the warning/taint to > > indicate if there are machines that unknowingly rely on this. > > The warning is being triggered on Qualcomm MSM8996, as well as the out-of-spec taint: Is this booting with ACPI or DT? > ------------[ cut here ]------------ > rtc-pm8xxx 400f000.qcom,spmi:pmic@0:rtc@6000: ARCH_DMA_MINALIGN smaller than CTR_EL0.CWG (64 < 128) > WARNING: CPU: 0 PID: 1 at arch/arm64/mm/dma-mapping.c:45 arch_setup_dma_ops+0xf8/0x10c [...] > This warning is triggered with nearly every driver probe, not only rtc-pm8xxx. I have a suspicion none of the reported devices actually do any DMA, so in practice it should be safe but we need to figure out why arch_setup_dma_ops() gets called. -- Catalin
