The patch titled Subject: lib/zlib: DFLTCC always switch to software inflate for Z_PACKET_FLUSH option has been added to the -mm mm-nonmm-unstable branch. Its filename is lib-zlib-dfltcc-always-switch-to-software-inflate-for-z_packet_flush-option.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/lib-zlib-dfltcc-always-switch-to-software-inflate-for-z_packet_flush-option.patch This patch will later appear in the mm-nonmm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Mikhail Zaslonko <zaslonko@xxxxxxxxxxxxx> Subject: lib/zlib: DFLTCC always switch to software inflate for Z_PACKET_FLUSH option Date: Thu, 26 Jan 2023 14:14:28 +0100 Since hardware inflate does not support Z_PACKET_FLUSH option (used exclusively by kernel PPP driver), always switch to software like we already do for Z_BLOCK flush option. Without this patch, PPP might get Z_DATA_ERROR return code from zlib_inflate() and disable zlib compression for the packets. Link: https://lkml.kernel.org/r/20230126131428.1222214-9-zaslonko@xxxxxxxxxxxxx Signed-off-by: Mikhail Zaslonko <zaslonko@xxxxxxxxxxxxx> Acked-by: Ilya Leoshkevich <iii@xxxxxxxxxxxxx> Cc: Heiko Carstens <hca@xxxxxxxxxxxxx> Cc: Vasily Gorbik <gor@xxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- lib/zlib_dfltcc/dfltcc_inflate.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/lib/zlib_dfltcc/dfltcc_inflate.c~lib-zlib-dfltcc-always-switch-to-software-inflate-for-z_packet_flush-option +++ a/lib/zlib_dfltcc/dfltcc_inflate.c @@ -95,8 +95,10 @@ dfltcc_inflate_action dfltcc_inflate( struct dfltcc_param_v0 *param = &dfltcc_state->param; dfltcc_cc cc; - if (flush == Z_BLOCK) { - /* DFLTCC does not support stopping on block boundaries */ + if (flush == Z_BLOCK || flush == Z_PACKET_FLUSH) { + /* DFLTCC does not support stopping on block boundaries (Z_BLOCK flush option) + * as well as the use of Z_PACKET_FLUSH option (used exclusively by PPP driver) + */ if (dfltcc_inflate_disable(strm)) { *ret = Z_STREAM_ERROR; return DFLTCC_INFLATE_BREAK; _ Patches currently in -mm which might be from zaslonko@xxxxxxxxxxxxx are lib-zlib-adjust-offset-calculation-for-dfltcc_state.patch lib-zlib-implement-switching-between-dfltcc-and-software.patch lib-zlib-fix-dfltcc-not-flushing-eobs-when-creating-raw-streams.patch lib-zlib-fix-dfltcc-ignoring-flush-modes-when-avail_in-==-0.patch lib-zlib-dfltcc-not-writing-header-bits-when-avail_out-==-0.patch lib-zlib-split-deflate-and-inflate-states-for-dfltcc.patch lib-zlib-dfltcc-support-inflate-with-small-window.patch lib-zlib-dfltcc-always-switch-to-software-inflate-for-z_packet_flush-option.patch