From: Marcelo Tosatti <marcelo.tosatti@cyclades.com>
To: Aristeu Sergio Rozanski Filho <aris@cathedrallabs.org>
Cc: linuxppc-embedded@ozlabs.org
Subject: Re: [PATCH] cpm_uart: fix xchar sending
Date: Fri, 25 Nov 2005 09:32:49 -0200 [thread overview]
Message-ID: <20051125113249.GA12701@logos.cnet> (raw)
In-Reply-To: <20051125143851.GJ7163@cathedrallabs.org>
On Fri, Nov 25, 2005 at 12:38:51PM -0200, 'Aristeu Sergio Rozanski Filho' wrote:
> Hi,
> while using SCC as uart and as serial console at same time I got this:
>
> [ 138.214258] Oops: kernel access of bad area, sig: 11 [#1]
> [ 138.218832] PREEMPT
> [ 138.221021] NIP: C0105C48 LR: C0105E60 SP: C03D5D10 REGS: c03d5c60 TRAP: 0300 Not tainted
> [ 138.229280] MSR: 00009032 EE: 1 PR: 0 FP: 0 ME: 1 IR/DR: 11
> [ 138.234713] DAR: 00000000, DSISR: C0000000
> [ 138.238745] TASK = c0349420[693] 'sh' THREAD: c03d4000
> [ 138.243754] Last syscall: 6
> [ 138.246402] GPR00: FEFFFFFF C03D5D10 C0349420 C01FB094 00000011 00000000 C1ECFBBC C01F24B0
> [ 138.254602] GPR08: FF002820 00000000 FF0028C0 00000000 19133615 A0CBCD5E 02000300 00000000
> [ 138.262804] GPR16: 00000000 01FF9E4C 00000000 7FA9A770 00000000 00000000 1003E2A8 00000000
> [ 138.271003] GPR24: 100562F4 7F9B6EF4 C0210000 C02A5338 C01FB094 00000000 C01FB094 C1F14574
> [ 138.279376] NIP [c0105c48] cpm_uart_tx_pump+0x4c/0x22c
> [ 138.284419] LR [c0105e60] cpm_uart_start_tx+0x38/0xb0
> [ 138.289361] Call trace:
> [ 138.291762] [c0105e60] cpm_uart_start_tx+0x38/0xb0
> [ 138.296547] [c010277c] uart_send_xchar+0x88/0x118
> [ 138.301244] [c01029a0] uart_unthrottle+0x6c/0x138
> [ 138.305942] [c00ece10] check_unthrottle+0x60/0x64
> [ 138.310641] [c00ecec4] reset_buffer_flags+0xb0/0x138
> [ 138.315595] [c00ecf64] n_tty_flush_buffer+0x18/0x78
> [ 138.320465] [c00e81b0] tty_ldisc_flush+0x64/0x7c
> [ 138.325078] [c010410c] uart_close+0xf0/0x2c8
> [ 138.329348] [c00e9c48] release_dev+0x724/0x8d4
> [ 138.333790] [c00e9e18] tty_release+0x20/0x3c
> [ 138.338061] [c006e544] __fput+0x178/0x1e0
> [ 138.342076] [c006c43c] filp_close+0x54/0xac
> [ 138.346261] [c0002d90] ret_from_syscall+0x0/0x44
> [ 138.352386] note: sh[693] exited with preempt_count 2
>
> a easy way to reproduce it is log into the system using ssh and do:
> cat >/dev/ttyCPM0
> then, switch to minicom and write some stuff on it back to ssh, a control C
> produce the oops
>
> this happens because uart_close calls uart_shutdown which frees xmit.buf,
> currently used by xchar sending in cpm_uart_tx_pump(), which seems wrong.
>
> the attached patch fixes the oops and also fixes xchar sending.
Looks good to me.
next prev parent reply other threads:[~2005-11-25 17:09 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2005-11-25 14:38 [PATCH] cpm_uart: fix xchar sending Aristeu Sergio Rozanski Filho
2005-11-25 11:32 ` Marcelo Tosatti [this message]
-- strict thread matches above, loose matches on Subject: below --
2005-11-25 13:03 Aristeu Sergio Rozanski Filho
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20051125113249.GA12701@logos.cnet \
--to=marcelo.tosatti@cyclades.com \
--cc=aris@cathedrallabs.org \
--cc=linuxppc-embedded@ozlabs.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.