e027e72ecc
When e.g. 8 bytes are to be read, sgm->consumed equals 8 immediately after sg_miter_next() call. The driver then increments it as bytes are read, so sgm->consumed becomes 16 and this warning triggers in sg_miter_stop(): WARN_ON(miter->consumed > miter->length); WARNING: CPU: 0 PID: 28 at lib/scatterlist.c:925 sg_miter_stop+0x2c/0x10c CPU: 0 PID: 28 Comm: kworker/0:2 Tainted: G W 6.9.0-rc5-dirty #249 Hardware name: Generic DT based system Workqueue: events_freezable mmc_rescan Call trace:. unwind_backtrace from show_stack+0x10/0x14 show_stack from dump_stack_lvl+0x44/0x5c dump_stack_lvl from __warn+0x78/0x16c __warn from warn_slowpath_fmt+0xb0/0x160 warn_slowpath_fmt from sg_miter_stop+0x2c/0x10c sg_miter_stop from moxart_request+0xb0/0x468 moxart_request from mmc_start_request+0x94/0xa8 mmc_start_request from mmc_wait_for_req+0x60/0xa8 mmc_wait_for_req from mmc_app_send_scr+0xf8/0x150 mmc_app_send_scr from mmc_sd_setup_card+0x1c/0x420 mmc_sd_setup_card from mmc_sd_init_card+0x12c/0x4dc mmc_sd_init_card from mmc_attach_sd+0xf0/0x16c mmc_attach_sd from mmc_rescan+0x1e0/0x298 mmc_rescan from process_scheduled_works+0x2e4/0x4ec process_scheduled_works from worker_thread+0x1ec/0x24c worker_thread from kthread+0xd4/0xe0 kthread from ret_from_fork+0x14/0x38 This patch adds initial zeroing of sgm->consumed. It is then incremented as bytes are read or written. Signed-off-by: Sergei Antonov <saproj@gmail.com> Cc: Linus Walleij <linus.walleij@linaro.org> Fixes: 3ee0e7c3e67c ("mmc: moxart-mmc: Use sg_miter for PIO") Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/20240422153607.963672-1-saproj@gmail.com Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.