[sparc64] Kernel unaligned access at TPC lzo1x_1_do_compress

[sparc64] Kernel unaligned access at TPC lzo1x_1_do_compress

[Anatoly Pugachev]

Hello!

trying to use zram block device, shows the following:

# zramctl -f -s 16g
# cat /sys/block/zram0/comp_algorithm
lzo [lzo-rle] lz4 lz4hc 842 zstd
# zramctl
NAME       ALGORITHM DISKSIZE  DATA COMPR TOTAL STREAMS MOUNTPOINT
/dev/zram0 lzo-rle        16G 10.4M    4K  112K      32

# mkfs.xfs /dev/zram0
...

[   71.095998] zram: Added device: zram0
[   71.765591] zram0: detected capacity change from 0 to 17179869184
[   80.058772] Kernel unaligned access at TPC[8f2534]
lzo1x_1_do_compress+0x1b4/0x820
[   80.073832] Kernel unaligned access at TPC[8f2534]
lzo1x_1_do_compress+0x1b4/0x820
[   80.073866] Kernel unaligned access at TPC[8f2534]
lzo1x_1_do_compress+0x1b4/0x820
[   80.074709] Kernel unaligned access at TPC[8f2534]
lzo1x_1_do_compress+0x1b4/0x820
[   80.074923] Kernel unaligned access at TPC[8f2534]
lzo1x_1_do_compress+0x1b4/0x820


all other tested compression algorithms (lzo, lz4, lz4hc, deflate,
842) work without producing kernel TPC.

Re: [sparc64] Kernel unaligned access at TPC lzo1x_1_do_compress

[Dave Rodgman]

Thanks Anatoly, I'll take a look at this. Could you please let me know the exact hardware you're running on?

thanks

Dave

________________________________________
From: linux-kernel-owner@vger.kernel.org <linux-kernel-owner@vger.kernel.org> on behalf of Anatoly Pugachev <matorola@gmail.com>
Sent: 08 September 2019 11:58:08
To: Sparc kernel list
Cc: Linux Kernel list
Subject: [sparc64] Kernel unaligned access at TPC lzo1x_1_do_compress

Hello!

trying to use zram block device, shows the following:

# zramctl -f -s 16g
# cat /sys/block/zram0/comp_algorithm
lzo [lzo-rle] lz4 lz4hc 842 zstd
# zramctl
NAME       ALGORITHM DISKSIZE  DATA COMPR TOTAL STREAMS MOUNTPOINT
/dev/zram0 lzo-rle        16G 10.4M    4K  112K      32

# mkfs.xfs /dev/zram0
...

[   71.095998] zram: Added device: zram0
[   71.765591] zram0: detected capacity change from 0 to 17179869184
[   80.058772] Kernel unaligned access at TPC[8f2534]
lzo1x_1_do_compress+0x1b4/0x820
[   80.073832] Kernel unaligned access at TPC[8f2534]
lzo1x_1_do_compress+0x1b4/0x820
[   80.073866] Kernel unaligned access at TPC[8f2534]
lzo1x_1_do_compress+0x1b4/0x820
[   80.074709] Kernel unaligned access at TPC[8f2534]
lzo1x_1_do_compress+0x1b4/0x820
[   80.074923] Kernel unaligned access at TPC[8f2534]
lzo1x_1_do_compress+0x1b4/0x820


all other tested compression algorithms (lzo, lz4, lz4hc, deflate,
842) work without producing kernel TPC.
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Re: [sparc64] Kernel unaligned access at TPC lzo1x_1_do_compress

[Anatoly Pugachev]

On Mon, Sep 9, 2019 at 1:11 PM Dave Rodgman <dave.rodgman@arm.com> wrote:
>
> Thanks Anatoly, I'll take a look at this. Could you please let me know the exact hardware you're running on?

Dave,

machine is a LDOM on T5-2 server.

OS is debian unstable/sid linux with latest git kernel, currently :

$ uname -a
Linux ttip 5.3.0-rc8-dirty #1211 SMP Mon Sep 9 10:20:40 MSK 2019
sparc64 GNU/Linux

-dirty cause non-mainline (yet) fix for IPC [1] and reverted
HAVE_GENERIC_GUP patch [2].

$ gcc --version
gcc (Debian 9.2.1-7) 9.2.1 20190905

$ ld -V
GNU ld (GNU Binutils for Debian) 2.32.51.20190821

$ ldd --version
ldd (Debian GLIBC 2.28-10) 2.28


I could give you  account on this box to test or fix kernel if you would like.

Thanks.

1. https://marc.info/?l=linux-kernel&m=156769723218727
2. https://marc.info/?l=linux-sparc&m=156026414826151