swh:1:snp:c7beb2432b7e93c4cf6ab09cd194c7c1998df2f9
Revision 55db4c64eddf37e31279ec15fe90314713bc9cfa authored by Linus Torvalds on 03 June 2011, 21:33:24 UTC, committed by Linus Torvalds on 03 June 2011, 21:33:24 UTC
This reverts commit b1c43f82c5aa265442f82dba31ce985ebb7aa71c. It was broken in so many ways, and results in random odd pty issues. It re-introduced the buggy schedule_work() in flush_to_ldisc() that can cause endless work-loops (see commit a5660b41af6a: "tty: fix endless work loop when the buffer fills up"). It also used an "unsigned int" return value fo the ->receive_buf() function, but then made multiple functions return a negative error code, and didn't actually check for the error in the caller. And it didn't actually work at all. BenH bisected down odd tty behavior to it: "It looks like the patch is causing some major malfunctions of the X server for me, possibly related to PTYs. For example, cat'ing a large file in a gnome terminal hangs the kernel for -minutes- in a loop of what looks like flush_to_ldisc/workqueue code, (some ftrace data in the quoted bits further down). ... Some more data: It -looks- like what happens is that the flush_to_ldisc work queue entry constantly re-queues itself (because the PTY is full ?) and the workqueue thread will basically loop forver calling it without ever scheduling, thus starving the consumer process that could have emptied the PTY." which is pretty much exactly the problem we fixed in a5660b41af6a. Milton Miller pointed out the 'unsigned int' issue. Reported-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Reported-by: Milton Miller <miltonm@bga.com> Cc: Stefan Bigler <stefan.bigler@keymile.com> Cc: Toby Gray <toby.gray@realvnc.com> Cc: Felipe Balbi <balbi@ti.com> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 parent 1fa7b6a
Tip revision: beaeb4f39bc31d5a5eb6d05465a86af4fe147732 authored by Linus Torvalds on 21 September 2020, 15:53:48 UTC
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Tip revision: beaeb4f
File | Mode | Size |
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Documentation | ||
arch | ||
block | ||
crypto | ||
drivers | ||
firmware | ||
fs | ||
include | ||
init | ||
ipc | ||
kernel | ||
lib | ||
mm | ||
net | ||
samples | ||
scripts | ||
security | ||
sound | ||
tools | ||
usr | ||
virt | ||
.gitignore | -rw-r--r-- | 966 bytes |
.mailmap | -rw-r--r-- | 4.2 KB |
COPYING | -rw-r--r-- | 18.3 KB |
CREDITS | -rw-r--r-- | 91.9 KB |
Kbuild | -rw-r--r-- | 2.4 KB |
Kconfig | -rw-r--r-- | 252 bytes |
MAINTAINERS | -rw-r--r-- | 189.8 KB |
Makefile | -rw-r--r-- | 52.6 KB |
README | -rw-r--r-- | 17.1 KB |
REPORTING-BUGS | -rw-r--r-- | 3.3 KB |
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