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vt: remove bogus lock dropping
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For hysterical raisins the vt layer drops and retakes locks in the write
method. This is a left over from the days when user/kernel data was passed
directly to the tty not pre-buffered.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Alan Cox authored and Linus Torvalds committed Oct 13, 2008
1 parent 15582d3 commit bf7a06b
Showing 1 changed file with 0 additions and 18 deletions.
18 changes: 0 additions & 18 deletions drivers/char/vt.c
Original file line number Diff line number Diff line change
Expand Up @@ -2136,27 +2136,9 @@ static int do_con_write(struct tty_struct *tty, const unsigned char *buf, int co
release_console_sem();
return 0;
}
release_console_sem();

orig_buf = buf;
orig_count = count;

/* At this point 'buf' is guaranteed to be a kernel buffer
* and therefore no access to userspace (and therefore sleeping)
* will be needed. The con_buf_mtx serializes all tty based
* console rendering and vcs write/read operations. We hold
* the console spinlock during the entire write.
*/

acquire_console_sem();

vc = tty->driver_data;
if (vc == NULL) {
printk(KERN_ERR "vt: argh, driver_data _became_ NULL !\n");
release_console_sem();
goto out;
}

himask = vc->vc_hi_font_mask;
charmask = himask ? 0x1ff : 0xff;

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