From: Pavel Machek <pavel@ucw.cz>
To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-kernel@vger.kernel.org, stable@vger.kernel.org,
Chris Wilson <chris@chris-wilson.co.uk>,
Mika Kuoppala <mika.kuoppala@linux.intel.com>,
Rodrigo Vivi <rodrigo.vivi@intel.com>
Subject: Re: [PATCH 4.19 01/71] drm/i915: Break up error capture compression loops with cond_resched()
Date: Mon, 9 Nov 2020 19:20:46 +0100 [thread overview]
Message-ID: <20201109182046.GA20488@amd> (raw)
In-Reply-To: <20201109125019.973892170@linuxfoundation.org>
[-- Attachment #1: Type: text/plain, Size: 1812 bytes --]
Hi!
> commit 7d5553147613b50149238ac1385c60e5c7cacb34 upstream.
>
> As the error capture will compress user buffers as directed to by the
> user, it can take an arbitrary amount of time and space. Break up the
> compression loops with a call to cond_resched(), that will allow other
> processes to schedule (avoiding the soft lockups) and also serve as a
> warning should we try to make this loop atomic in the future.
This was queued for 4.19-stable, but is very likely wrong.
> Testcase: igt/gem_exec_capture/many-*
> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
> Cc: stable@vger.kernel.org
> Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
> Link: https://patchwork.freedesktop.org/patch/msgid/20200916090059.3189-2-chris@chris-wilson.co.uk
> (cherry picked from commit 293f43c80c0027ff9299036c24218ac705ce584e)
> Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> @@ -347,6 +349,7 @@ static int compress_page(struct compress
> if (!i915_memcpy_from_wc(ptr, src, PAGE_SIZE))
> memcpy(ptr, src, PAGE_SIZE);
> dst->pages[dst->page_count++] = ptr;
> + cond_resched();
>
> return 0;
> }
4.19 compress_page begins with
static int compress_page(struct compress *c,
...
page = __get_free_page(GFP_ATOMIC | __GFP_NOWARN);
and likely may not sleep. That changed with commit
a42f45a2a85998453078, but that one is not present in 4.19..
I believe we don't need this in stable: dumping of error file will not
take so long to trigger softlockup detectors...
Best regards,
Pavel
>
--
http://www.livejournal.com/~pavelmachek
[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 181 bytes --]
next prev parent reply other threads:[~2020-11-09 18:20 UTC|newest]
Thread overview: 87+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-11-09 12:54 [PATCH 4.19 00/71] 4.19.156-rc1 review Greg Kroah-Hartman
2020-11-09 12:54 ` [PATCH 4.19 01/71] drm/i915: Break up error capture compression loops with cond_resched() Greg Kroah-Hartman
2020-11-09 18:20 ` Pavel Machek [this message]
2020-11-09 12:54 ` [PATCH 4.19 02/71] tipc: fix use-after-free in tipc_bcast_get_mode Greg Kroah-Hartman
2020-11-09 12:54 ` [PATCH 4.19 03/71] ptrace: fix task_join_group_stop() for the case when current is traced Greg Kroah-Hartman
2020-11-09 12:54 ` [PATCH 4.19 04/71] cadence: force nonlinear buffers to be cloned Greg Kroah-Hartman
2020-11-09 12:54 ` [PATCH 4.19 05/71] chelsio/chtls: fix memory leaks caused by a race Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 06/71] chelsio/chtls: fix always leaking ctrl_skb Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 07/71] gianfar: Replace skb_realloc_headroom with skb_cow_head for PTP Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 08/71] gianfar: Account for Tx PTP timestamp in the skb headroom Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 09/71] net: usb: qmi_wwan: add Telit LE910Cx 0x1230 composition Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 10/71] sctp: Fix COMM_LOST/CANT_STR_ASSOC err reporting on big-endian platforms Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 11/71] sfp: Fix error handing in sfp_probe() Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 12/71] blktrace: fix debugfs use after free Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 13/71] btrfs: extent_io: Kill the forward declaration of flush_write_bio Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 14/71] btrfs: extent_io: Move the BUG_ON() in flush_write_bio() one level up Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 15/71] Revert "btrfs: flush write bio if we loop in extent_write_cache_pages" Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 16/71] btrfs: flush write bio if we loop in extent_write_cache_pages Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 17/71] btrfs: extent_io: Handle errors better in extent_write_full_page() Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 18/71] btrfs: extent_io: Handle errors better in btree_write_cache_pages() Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 19/71] btrfs: extent_io: add proper error handling to lock_extent_buffer_for_io() Greg Kroah-Hartman
2020-11-11 12:44 ` Pavel Machek
2020-11-11 14:39 ` Ben Hutchings
2020-11-12 16:06 ` Sasha Levin
2020-11-09 12:55 ` [PATCH 4.19 20/71] Btrfs: fix unwritten extent buffers and hangs on future writeback attempts Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 21/71] btrfs: Dont submit any btree write bio if the fs has errors Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 22/71] btrfs: Move btrfs_check_chunk_valid() to tree-check.[ch] and export it Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 23/71] btrfs: tree-checker: Make chunk item checker messages more readable Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 24/71] btrfs: tree-checker: Make btrfs_check_chunk_valid() return EUCLEAN instead of EIO Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 25/71] btrfs: tree-checker: Check chunk item at tree block read time Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 26/71] btrfs: tree-checker: Verify dev item Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 27/71] btrfs: tree-checker: Fix wrong check on max devid Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 28/71] btrfs: tree-checker: Enhance chunk checker to validate chunk profile Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 29/71] btrfs: tree-checker: Verify inode item Greg Kroah-Hartman
2020-11-11 13:13 ` Pavel Machek
2020-11-11 13:30 ` Qu Wenruo
2020-11-11 13:38 ` Pavel Machek
2020-11-11 14:04 ` Qu Wenruo
2020-11-09 12:55 ` [PATCH 4.19 30/71] btrfs: tree-checker: fix the error message for transid error Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 31/71] Fonts: Replace discarded const qualifier Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 32/71] ALSA: usb-audio: Add implicit feedback quirk for Zoom UAC-2 Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 33/71] ALSA: usb-audio: add usb vendor id as DSD-capable for Khadas devices Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 34/71] ALSA: usb-audio: Add implicit feedback quirk for Qu-16 Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 35/71] ALSA: usb-audio: Add implicit feedback quirk for MODX Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 36/71] mm: mempolicy: fix potential pte_unmap_unlock pte error Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 37/71] lib/crc32test: remove extra local_irq_disable/enable Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 38/71] kthread_worker: prevent queuing delayed work from timer_fn when it is being canceled Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 39/71] mm: always have io_remap_pfn_range() set pgprot_decrypted() Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 40/71] gfs2: Wake up when sd_glock_disposal becomes zero Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 41/71] ring-buffer: Fix recursion protection transitions between interrupt context Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 42/71] ftrace: Fix recursion check for NMI test Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 43/71] ftrace: Handle tracing when switching between context Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 44/71] tracing: Fix out of bounds write in get_trace_buf Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 45/71] futex: Handle transient "ownerless" rtmutex state correctly Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 46/71] ARM: dts: sun4i-a10: fix cpu_alert temperature Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 47/71] x86/kexec: Use up-to-dated screen_info copy to fill boot params Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 48/71] of: Fix reserved-memory overlap detection Greg Kroah-Hartman
2020-11-11 12:53 ` Pavel Machek
2020-11-11 14:34 ` Vincent Whitchurch
2020-11-09 12:55 ` [PATCH 4.19 49/71] blk-cgroup: Fix memleak on error path Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 50/71] blk-cgroup: Pre-allocate tree node on blkg_conf_prep Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 51/71] scsi: core: Dont start concurrent async scan on same host Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 52/71] vsock: use ns_capable_noaudit() on socket create Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 53/71] drm/vc4: drv: Add error handding for bind Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 54/71] ACPI: NFIT: Fix comparison to -ENXIO Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 55/71] vt: Disable KD_FONT_OP_COPY Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 56/71] fork: fix copy_process(CLONE_PARENT) race with the exiting ->real_parent Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 57/71] serial: 8250_mtk: Fix uart_get_baud_rate warning Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 58/71] serial: txx9: add missing platform_driver_unregister() on error in serial_txx9_init Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 59/71] USB: serial: cyberjack: fix write-URB completion race Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 60/71] USB: serial: option: add Quectel EC200T module support Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 61/71] USB: serial: option: add LE910Cx compositions 0x1203, 0x1230, 0x1231 Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 62/71] USB: serial: option: add Telit FN980 composition 0x1055 Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 63/71] USB: Add NO_LPM quirk for Kingston flash drive Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 64/71] usb: mtu3: fix panic in mtu3_gadget_stop() Greg Kroah-Hartman
2020-11-09 12:55 ` [PATCH 4.19 65/71] ARC: stack unwinding: avoid indefinite looping Greg Kroah-Hartman
2020-11-09 12:56 ` [PATCH 4.19 66/71] Revert "ARC: entry: fix potential EFA clobber when TIF_SYSCALL_TRACE" Greg Kroah-Hartman
2020-11-09 12:56 ` [PATCH 4.19 67/71] PM: runtime: Resume the device earlier in __device_release_driver() Greg Kroah-Hartman
2020-11-09 12:56 ` [PATCH 4.19 68/71] perf/core: Fix a memory leak in perf_event_parse_addr_filter() Greg Kroah-Hartman
2020-11-09 12:56 ` [PATCH 4.19 69/71] tools: perf: Fix build error in v4.19.y Greg Kroah-Hartman
2020-11-09 12:56 ` [PATCH 4.19 70/71] net: dsa: read mac address from DT for slave device Greg Kroah-Hartman
2020-11-09 12:56 ` [PATCH 4.19 71/71] arm64: dts: marvell: espressobin: Add ethernet switch aliases Greg Kroah-Hartman
2020-11-09 19:22 ` [PATCH 4.19 00/71] 4.19.156-rc1 review Pavel Machek
2020-11-09 23:07 ` Guenter Roeck
2020-11-09 23:22 ` Shuah Khan
2020-11-10 7:44 ` Naresh Kamboju
2020-11-19 8:10 ` Pavel Machek
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=20201109182046.GA20488@amd \
--to=pavel@ucw.cz \
--cc=chris@chris-wilson.co.uk \
--cc=gregkh@linuxfoundation.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mika.kuoppala@linux.intel.com \
--cc=rodrigo.vivi@intel.com \
--cc=stable@vger.kernel.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).