Hi Md, quic_mdalam@xxxxxxxxxxx wrote on Thu, 14 Apr 2022 21:00:17 +0530: > This patch fixes a memory corruption that occurred in the > nand_scan() path for Hynix nand device. > > On boot, for Hynix nand device will panic at a weird place: > | Unable to handle kernel NULL pointer dereference at virtual > address 00000070 > | [00000070] *pgd=00000000 > | Internal error: Oops: 5 [#1] PREEMPT SMP ARM > | Modules linked in: > | CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.17.0-01473-g13ae1769cfb0 > #38 > | Hardware name: Generic DT based system > | PC is at nandc_set_reg+0x8/0x1c > | LR is at qcom_nandc_command+0x20c/0x5d0 > | pc : [<c088b74c>] lr : [<c088d9c8>] psr: 00000113 > | sp : c14adc50 ip : c14ee208 fp : c0cc970c > | r10: 000000a3 r9 : 00000000 r8 : 00000040 > | r7 : c16f6a00 r6 : 00000090 r5 : 00000004 r4 :c14ee040 > | r3 : 00000000 r2 : 0000000b r1 : 00000000 r0 :c14ee040 > | Flags: nzcv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none > | Control: 10c5387d Table: 8020406a DAC: 00000051 > | Register r0 information: slab kmalloc-2k start c14ee000 pointer offset > 64 size 2048 > | Process swapper/0 (pid: 1, stack limit = 0x(ptrval)) > | nandc_set_reg from qcom_nandc_command+0x20c/0x5d0 > | qcom_nandc_command from nand_readid_op+0x198/0x1e8 > | nand_readid_op from hynix_nand_has_valid_jedecid+0x30/0x78 > | hynix_nand_has_valid_jedecid from hynix_nand_init+0xb8/0x454 > | hynix_nand_init from nand_scan_with_ids+0xa30/0x14a8 > | nand_scan_with_ids from qcom_nandc_probe+0x648/0x7b0 > | qcom_nandc_probe from platform_probe+0x58/0xac > > The problem is that the nand_scan()'s qcom_nand_attach_chip callback > is updating the nandc->max_cwperpage from 1 to 4.This causes the > sg_init_table of clear_bam_transaction() in the driver's > qcom_nandc_command() to memset much more than what was initially > allocated by alloc_bam_transaction(). > > This patch will update nandc->max_cwperpage 1 to 4 after nand_scan() > returns, and remove updating nandc->max_cwperpage from > qcom_nand_attach_chip call back. Please update also the commit log. Fixes: ? Cc: stable ? > Signed-off-by: Md Sadre Alam <quic_mdalam@xxxxxxxxxxx> > Signed-off-by: Sricharan R <quic_srichara@xxxxxxxxxxx> > --- > [V2] Thanks, Miquèl
