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Christophe Leroy 9ee7148fa1 eeprom: at25: Use DMA safe buffers
commit 5b47b751b7 upstream.

Reading EEPROM fails with following warning:

[   16.357496] ------------[ cut here ]------------
[   16.357529] fsl_spi b01004c0.spi: rejecting DMA map of vmalloc memory
[   16.357698] WARNING: CPU: 0 PID: 371 at include/linux/dma-mapping.h:326 fsl_spi_cpm_bufs+0x2a0/0x2d8
[   16.357775] CPU: 0 PID: 371 Comm: od Not tainted 5.16.11-s3k-dev-01743-g19beecbfe9d6-dirty #109
[   16.357806] NIP:  c03fbc9c LR: c03fbc9c CTR: 00000000
[   16.357825] REGS: e68d9b20 TRAP: 0700   Not tainted  (5.16.11-s3k-dev-01743-g19beecbfe9d6-dirty)
[   16.357849] MSR:  00029032 <EE,ME,IR,DR,RI>  CR: 24002282  XER: 00000000
[   16.357931]
[   16.357931] GPR00: c03fbc9c e68d9be0 c26d06a0 00000039 00000001 c0d36364 c0e96428 00000027
[   16.357931] GPR08: 00000001 00000000 00000023 3fffc000 24002282 100d3dd6 100a2ffc 00000000
[   16.357931] GPR16: 100cd280 100b0000 00000000 aff54f7e 100d0000 100d0000 00000001 100cf328
[   16.357931] GPR24: 100cf328 00000000 00000003 e68d9e30 c156b410 e67ab4c0 e68d9d38 c24ab278
[   16.358253] NIP [c03fbc9c] fsl_spi_cpm_bufs+0x2a0/0x2d8
[   16.358292] LR [c03fbc9c] fsl_spi_cpm_bufs+0x2a0/0x2d8
[   16.358325] Call Trace:
[   16.358336] [e68d9be0] [c03fbc9c] fsl_spi_cpm_bufs+0x2a0/0x2d8 (unreliable)
[   16.358388] [e68d9c00] [c03fcb44] fsl_spi_bufs.isra.0+0x94/0x1a0
[   16.358436] [e68d9c20] [c03fd970] fsl_spi_do_one_msg+0x254/0x3dc
[   16.358483] [e68d9cb0] [c03f7e50] __spi_pump_messages+0x274/0x8a4
[   16.358529] [e68d9ce0] [c03f9d30] __spi_sync+0x344/0x378
[   16.358573] [e68d9d20] [c03fb52c] spi_sync+0x34/0x60
[   16.358616] [e68d9d30] [c03b4dec] at25_ee_read+0x138/0x1a8
[   16.358667] [e68d9e50] [c04a8fb8] bin_attr_nvmem_read+0x98/0x110
[   16.358725] [e68d9e60] [c0204b14] kernfs_fop_read_iter+0xc0/0x1fc
[   16.358774] [e68d9e80] [c0168660] vfs_read+0x284/0x410
[   16.358821] [e68d9f00] [c016925c] ksys_read+0x6c/0x11c
[   16.358863] [e68d9f30] [c00160e0] ret_from_syscall+0x0/0x28
...
[   16.359608] ---[ end trace a4ce3e34afef0cb5 ]---
[   16.359638] fsl_spi b01004c0.spi: unable to map tx dma

This is due to the AT25 driver using buffers on stack, which is not
possible with CONFIG_VMAP_STACK.

As mentionned in kernel Documentation (Documentation/spi/spi-summary.rst):

  - Follow standard kernel rules, and provide DMA-safe buffers in
    your messages.  That way controller drivers using DMA aren't forced
    to make extra copies unless the hardware requires it (e.g. working
    around hardware errata that force the use of bounce buffering).

Modify the driver to use a buffer located in the at25 device structure
which is allocated via kmalloc during probe.

Protect writes in this new buffer with the driver's mutex.

Fixes: b587b13a4f ("[PATCH] SPI eeprom driver")
Cc: stable <stable@kernel.org>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Link: https://lore.kernel.org/r/230a9486fc68ea0182df46255e42a51099403642.1648032613.git.christophe.leroy@csgroup.eu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-05-09 09:16:14 +02:00
arch arm64: dts: qcom: add IPA qcom,qmp property 2022-04-27 14:41:17 +02:00
block block/compat_ioctl: fix range check in BLKGETSIZE 2022-04-27 14:40:54 +02:00
certs certs: Fix build error when CONFIG_MODULE_SIG_KEY is empty 2022-01-23 00:08:44 +09:00
crypto crypto: xts - Add softdep on ecb 2022-04-08 13:58:36 +02:00
Documentation ext4, doc: fix incorrect h_reserved size 2022-04-27 14:41:16 +02:00
drivers eeprom: at25: Use DMA safe buffers 2022-05-09 09:16:14 +02:00
fs kernfs: fix NULL dereferencing in kernfs_remove 2022-05-09 09:16:14 +02:00
include fs: fix acl translation 2022-04-27 14:41:14 +02:00
init init/main.c: return 1 from handled __setup() functions 2022-04-13 19:27:23 +02:00
ipc ipc/sem: do not sleep with a spin lock held 2022-02-04 09:25:05 -08:00
kernel perf/core: Fix perf_mmap fail when CONFIG_PERF_USE_VMALLOC enabled 2022-04-27 14:41:12 +02:00
lib XArray: Disallow sibling entries of nodes 2022-04-27 14:41:05 +02:00
LICENSES LICENSES/LGPL-2.1: Add LGPL-2.1-or-later as valid identifiers 2021-12-16 14:33:10 +01:00
mm mm/mmu_notifier.c: fix race in mmu_interval_notifier_remove() 2022-04-27 14:41:11 +02:00
net openvswitch: fix OOB access in reserve_sfa_size() 2022-04-27 14:41:14 +02:00
samples samples/bpf, xdpsock: Fix race when running for fix duration of time 2022-04-08 13:58:18 +02:00
scripts gcc-plugins: latent_entropy: use /dev/urandom 2022-04-20 09:36:24 +02:00
security Fix incorrect type in assignment of ipv6 port for audit 2022-04-08 13:58:37 +02:00
sound ASoC: SOF: topology: cleanup dailinks on widget unload 2022-04-27 14:41:17 +02:00
tools perf report: Set PERF_SAMPLE_DATA_SRC bit for Arm SPE event 2022-04-27 14:41:13 +02:00
usr kbuild: remove include/linux/cyclades.h from header file check 2022-01-27 08:51:08 +01:00
virt KVM: avoid NULL pointer dereference in kvm_dirty_ring_push 2022-04-13 19:27:41 +02:00
.clang-format genirq/msi: Make interrupt allocation less convoluted 2021-12-16 22:22:20 +01:00
.cocciconfig
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore .gitignore: ignore only top-level modules.builtin 2021-05-02 00:43:35 +09:00
.mailmap MAINTAINERS: Update Jisheng's email address 2022-03-08 17:30:32 +01:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: replace a Microchip AT91 maintainer 2022-02-09 11:30:01 +01:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS net: dsa: realtek-smi: move to subdirectory 2022-04-08 13:58:12 +02:00
Makefile Linux 5.17.5 2022-04-27 14:41:17 +02:00
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