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Roman Gushchin e8b7445355 net: macb: fix a memory corruption in extended buffer descriptor mode
For quite some time we were chasing a bug which looked like a sudden
permanent failure of networking and mmc on some of our devices.
The bug was very sensitive to any software changes and even more to
any kernel debug options.

Finally we got a setup where the problem was reproducible with
CONFIG_DMA_API_DEBUG=y and it revealed the issue with the rx dma:

[   16.992082] ------------[ cut here ]------------
[   16.996779] DMA-API: macb ff0b0000.ethernet: device driver tries to free DMA memory it has not allocated [device address=0x0000000875e3e244] [size=1536 bytes]
[   17.011049] WARNING: CPU: 0 PID: 85 at kernel/dma/debug.c:1011 check_unmap+0x6a0/0x900
[   17.018977] Modules linked in: xxxxx
[   17.038823] CPU: 0 PID: 85 Comm: irq/55-8000f000 Not tainted 5.4.0 #28
[   17.045345] Hardware name: xxxxx
[   17.049528] pstate: 60000005 (nZCv daif -PAN -UAO)
[   17.054322] pc : check_unmap+0x6a0/0x900
[   17.058243] lr : check_unmap+0x6a0/0x900
[   17.062163] sp : ffffffc010003c40
[   17.065470] x29: ffffffc010003c40 x28: 000000004000c03c
[   17.070783] x27: ffffffc010da7048 x26: ffffff8878e38800
[   17.076095] x25: ffffff8879d22810 x24: ffffffc010003cc8
[   17.081407] x23: 0000000000000000 x22: ffffffc010a08750
[   17.086719] x21: ffffff8878e3c7c0 x20: ffffffc010acb000
[   17.092032] x19: 0000000875e3e244 x18: 0000000000000010
[   17.097343] x17: 0000000000000000 x16: 0000000000000000
[   17.102647] x15: ffffff8879e4a988 x14: 0720072007200720
[   17.107959] x13: 0720072007200720 x12: 0720072007200720
[   17.113261] x11: 0720072007200720 x10: 0720072007200720
[   17.118565] x9 : 0720072007200720 x8 : 000000000000022d
[   17.123869] x7 : 0000000000000015 x6 : 0000000000000098
[   17.129173] x5 : 0000000000000000 x4 : 0000000000000000
[   17.134475] x3 : 00000000ffffffff x2 : ffffffc010a1d370
[   17.139778] x1 : b420c9d75d27bb00 x0 : 0000000000000000
[   17.145082] Call trace:
[   17.147524]  check_unmap+0x6a0/0x900
[   17.151091]  debug_dma_unmap_page+0x88/0x90
[   17.155266]  gem_rx+0x114/0x2f0
[   17.158396]  macb_poll+0x58/0x100
[   17.161705]  net_rx_action+0x118/0x400
[   17.165445]  __do_softirq+0x138/0x36c
[   17.169100]  irq_exit+0x98/0xc0
[   17.172234]  __handle_domain_irq+0x64/0xc0
[   17.176320]  gic_handle_irq+0x5c/0xc0
[   17.179974]  el1_irq+0xb8/0x140
[   17.183109]  xiic_process+0x5c/0xe30
[   17.186677]  irq_thread_fn+0x28/0x90
[   17.190244]  irq_thread+0x208/0x2a0
[   17.193724]  kthread+0x130/0x140
[   17.196945]  ret_from_fork+0x10/0x20
[   17.200510] ---[ end trace 7240980785f81d6f ]---

[  237.021490] ------------[ cut here ]------------
[  237.026129] DMA-API: exceeded 7 overlapping mappings of cacheline 0x0000000021d79e7b
[  237.033886] WARNING: CPU: 0 PID: 0 at kernel/dma/debug.c:499 add_dma_entry+0x214/0x240
[  237.041802] Modules linked in: xxxxx
[  237.061637] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G        W         5.4.0 #28
[  237.068941] Hardware name: xxxxx
[  237.073116] pstate: 80000085 (Nzcv daIf -PAN -UAO)
[  237.077900] pc : add_dma_entry+0x214/0x240
[  237.081986] lr : add_dma_entry+0x214/0x240
[  237.086072] sp : ffffffc010003c30
[  237.089379] x29: ffffffc010003c30 x28: ffffff8878a0be00
[  237.094683] x27: 0000000000000180 x26: ffffff8878e387c0
[  237.099987] x25: 0000000000000002 x24: 0000000000000000
[  237.105290] x23: 000000000000003b x22: ffffffc010a0fa00
[  237.110594] x21: 0000000021d79e7b x20: ffffffc010abe600
[  237.115897] x19: 00000000ffffffef x18: 0000000000000010
[  237.121201] x17: 0000000000000000 x16: 0000000000000000
[  237.126504] x15: ffffffc010a0fdc8 x14: 0720072007200720
[  237.131807] x13: 0720072007200720 x12: 0720072007200720
[  237.137111] x11: 0720072007200720 x10: 0720072007200720
[  237.142415] x9 : 0720072007200720 x8 : 0000000000000259
[  237.147718] x7 : 0000000000000001 x6 : 0000000000000000
[  237.153022] x5 : ffffffc010003a20 x4 : 0000000000000001
[  237.158325] x3 : 0000000000000006 x2 : 0000000000000007
[  237.163628] x1 : 8ac721b3a7dc1c00 x0 : 0000000000000000
[  237.168932] Call trace:
[  237.171373]  add_dma_entry+0x214/0x240
[  237.175115]  debug_dma_map_page+0xf8/0x120
[  237.179203]  gem_rx_refill+0x190/0x280
[  237.182942]  gem_rx+0x224/0x2f0
[  237.186075]  macb_poll+0x58/0x100
[  237.189384]  net_rx_action+0x118/0x400
[  237.193125]  __do_softirq+0x138/0x36c
[  237.196780]  irq_exit+0x98/0xc0
[  237.199914]  __handle_domain_irq+0x64/0xc0
[  237.204000]  gic_handle_irq+0x5c/0xc0
[  237.207654]  el1_irq+0xb8/0x140
[  237.210789]  arch_cpu_idle+0x40/0x200
[  237.214444]  default_idle_call+0x18/0x30
[  237.218359]  do_idle+0x200/0x280
[  237.221578]  cpu_startup_entry+0x20/0x30
[  237.225493]  rest_init+0xe4/0xf0
[  237.228713]  arch_call_rest_init+0xc/0x14
[  237.232714]  start_kernel+0x47c/0x4a8
[  237.236367] ---[ end trace 7240980785f81d70 ]---

Lars was fast to find an explanation: according to the datasheet
bit 2 of the rx buffer descriptor entry has a different meaning in the
extended mode:
  Address [2] of beginning of buffer, or
  in extended buffer descriptor mode (DMA configuration register [28] = 1),
  indicates a valid timestamp in the buffer descriptor entry.

The macb driver didn't mask this bit while getting an address and it
eventually caused a memory corruption and a dma failure.

The problem is resolved by explicitly clearing the problematic bit
if hw timestamping is used.

Fixes: 7b42961480 ("net: macb: Add support for PTP timestamps in DMA descriptors")
Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Co-developed-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Link: https://lore.kernel.org/r/20230412232144.770336-1-roman.gushchin@linux.dev
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-13 10:05:07 -07:00
arch bpf-for-netdev 2023-04-07 18:23:37 -07:00
block block: remove obsolete config BLOCK_COMPAT 2023-03-16 09:35:44 -06:00
certs Kbuild updates for v6.3 2023-02-26 11:53:25 -08:00
crypto asymmetric_keys: log on fatal failures in PE/pkcs7 2023-03-21 16:23:56 +00:00
Documentation tcp: restrict net.ipv4.tcp_app_win 2023-04-07 08:19:11 +01:00
drivers net: macb: fix a memory corruption in extended buffer descriptor mode 2023-04-13 10:05:07 -07:00
fs nfsd-6.3 fixes: 2023-04-04 11:20:55 -07:00
include rtnetlink: Restore RTM_NEW/DELLINK notification behavior 2023-04-12 20:47:58 -07:00
init bootconfig: Change message if no bootconfig with CONFIG_BOOT_CONFIG_FORCE=y 2023-03-22 22:21:43 +09:00
io_uring io_uring-6.3-2023-03-30 2023-03-31 12:30:13 -07:00
ipc Merge branch 'work.namespace' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2023-02-24 19:20:07 -08:00
kernel tracing: Free error logs of tracing instances 2023-04-05 09:54:37 -04:00
lib Fixes for 6.3-rc3: 2023-03-25 12:57:34 -07:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
mm 21 hotfixes, 8 of which are cc:stable. 11 are for MM, the remainder are 2023-03-24 18:06:11 -07:00
net udp6: fix potential access to stale information 2023-04-13 10:04:37 -07:00
rust Rust fixes for 6.3-rc1 2023-03-03 14:51:15 -08:00
samples LoongArch changes for v6.3 2023-03-01 09:27:00 -08:00
scripts Kbuild fixes for v6.3 (2nd) 2023-04-01 09:25:17 -07:00
security keys: Do not cache key in task struct if key is requested from kernel thread 2023-03-21 16:22:40 +00:00
sound ALSA: hda/hdmi: Preserve the previous PCM device upon re-enablement 2023-04-01 18:05:48 +02:00
tools selftests: add the missing CONFIG_IP_SCTP in net config 2023-04-13 10:04:55 -07:00
usr usr/gen_init_cpio.c: remove unnecessary -1 values from int file 2022-10-03 14:21:44 -07:00
virt KVM: PPC: Make KVM_CAP_IRQFD_RESAMPLE platform dependent 2023-03-31 11:19:05 -04:00
.clang-format cpumask: re-introduce constant-sized cpumask optimizations 2023-03-05 14:30:34 -08:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore get_maintainer: add Alan to .get_maintainer.ignore 2022-08-20 15:17:44 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for *.dtso files 2023-02-26 15:28:23 +09:00
.gitignore kbuild: rpm-pkg: move source components to rpmbuild/SOURCES 2023-03-16 22:45:56 +09:00
.mailmap mailmap: add entries for Richard Leitner 2023-03-23 17:18:35 -07:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS There is no particular theme here - mainly quick hits all over the tree. 2023-02-23 17:55:40 -08:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS Driver core fixes for 6.3-rc5 2023-04-02 10:10:16 -07:00
Makefile Linux 6.3-rc5 2023-04-02 14:29:29 -07:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

Linux kernel
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