Tech/storage/all #557
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Tech/storage/all #557
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Enable UFS on x1e80100 SoC. Signed-off-by: Pradeep P V K <pragalla@qti.qualcomm.com>
Enable UFS for HAMOA-IOT-EVK board. Signed-off-by: Pradeep P V K <pragalla@qti.qualcomm.com>
The nvme_pci_prp_iter_next function had a race condition where dma_need_unmap() could return true indicating DMA unmapping is needed, but iod->dma_vecs was NULL, causing a NULL pointer dereference. This occurred because: 1. dma_vecs allocation happens in nvme_pci_setup_data_prp() 2. nvme_pci_prp_iter_next() checks dma_need_unmap() but doesn't verify if dma_vecs allocation was successful 3. If allocation failed or race condition occurred, accessing dma_vecs[0] would cause kernel crash The crash manifested as: - dma_size:0 unmap:0 initially, then dma_size:0 unmap:1 - nr_dma_vecs:0 dma_vecs:0x0 (NULL pointer) - Unable to handle kernel NULL pointer dereference at virtual address 0x0. Fix by adding iod->dma_vecs NULL check to the condition in nvme_pci_prp_iter_next(), ensuring DMA vector operations only occur when the dma_vecs array has been successfully allocated. Co-developed-by: Nitin Rawat <nitin.rawat@oss.qualcomm.com> Signed-off-by: Nitin Rawat <nitin.rawat@oss.qualcomm.com> Signed-off-by: Pradeep P V K <pradeep.pragallapati@oss.qualcomm.com>
The current devfreq downdifferential threshold of 5% causes overly aggressive frequency downscaling, leading to performance degradation sometimes during sequential read workloads. Update the UFS devfreq downdifferential threshold to 65. This widens the hysteresis window and prevents overly aggressive downscaling, ensuring that frequency is maintained for loads above 5% and scaling down occurs only when utilization falls below this level, while scale-up still triggers above the 70% threshold. Signed-off-by: Nitin Rawat <nitin.rawat@oss.qualcomm.com> Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com> Signed-off-by: Pradeep P V K <pradeep.pragallapati@oss.qualcomm.com> Link: https://lore.kernel.org/all/20260122141331.239354-4-nitin.rawat@oss.qualcomm.com/
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