On Wed, 1 Nov 2023, Linux regression tracking (Thorsten Leemhuis) wrote: > > #regzbot introduced: b8aa7dc5c753 > > BTW: Eric, thx for this. > > Boris, Arnaud, Srujana, and Mikulas, could you maybe comment on this? I > understand that this is not some everyday regression due to deadlock > risk, but it nevertheless would be good to get this resolved somehow to > stay in line with our "no regressions" rule. > > Ciao, Thorsten (wearing his 'the Linux kernel's regression tracker' hat) Hi The driver drivers/crypto/marvell/cesa/cipher.c uses GFP_ATOMIC allocations (see mv_cesa_skcipher_dma_req_init). So, it is not really safe to use it for dm-crypt. GFP_ATOMIC allocations may fail anytime (for example, they fill fail if the machine receives too many network packets in a short timeframe and runs temporarily out of memory). And when the GFP_ATOMIC allocation fails, you get a write I/O error and data corruption. It could be possible to change it to use GFP_NOIO allocations, then we would risk deadlock instead of data corruption. The best thing would be to convert the driver to use mempools. Mikulas
