From: Frieder Schrempf <frieder.schrempf(a)kontron.de>
On i.MX6 the DMA event for the RX channel of UART6 is '0'. To fix
the broken DMA support for UART6, we change the check for event_id0
to include '0' as a valid id.
Fixes: 1ec1e82f2510 ("dmaengine: Add Freescale i.MX SDMA support")
Cc: stable(a)vger.kernel.org
Signed-off-by: Frieder Schrempf <frieder.schrempf(a)kontron.de>
---
drivers/dma/imx-sdma.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c
index 066b21a32232..3d4aac97b1fc 100644
--- a/drivers/dma/imx-sdma.c
+++ b/drivers/dma/imx-sdma.c
@@ -1331,7 +1331,7 @@ static void sdma_free_chan_resources(struct dma_chan *chan)
sdma_channel_synchronize(chan);
- if (sdmac->event_id0)
+ if (sdmac->event_id0 >= 0)
sdma_event_disable(sdmac, sdmac->event_id0);
if (sdmac->event_id1)
sdma_event_disable(sdmac, sdmac->event_id1);
@@ -1631,7 +1631,7 @@ static int sdma_config(struct dma_chan *chan,
memcpy(&sdmac->slave_config, dmaengine_cfg, sizeof(*dmaengine_cfg));
/* Set ENBLn earlier to make sure dma request triggered after that */
- if (sdmac->event_id0) {
+ if (sdmac->event_id0 >= 0) {
if (sdmac->event_id0 >= sdmac->sdma->drvdata->num_events)
return -EINVAL;
sdma_event_enable(sdmac, sdmac->event_id0);
--
2.17.1
On Thu, Feb 20, 2020 at 4:49 AM Sasha Levin <sashal(a)kernel.org> wrote:
>
> Hi,
>
> [This is an automated email]
>
> This commit has been processed because it contains a -stable tag.
> The stable tag indicates that it's relevant for the following trees: all
>
> The bot has tested the following trees: v5.5.4, v5.4.20, v4.19.104, v4.14.171, v4.9.214, v4.4.214.
>
> v5.5.4: Build OK!
> v5.4.20: Build OK!
> v4.19.104: Build OK!
> v4.14.171: Build failed! Errors:
> drivers/usb/dwc3/gadget.c:1098:12: error: `remaining` undeclared (first use in this function)
>
> v4.9.214: Failed to apply! Possible dependencies:
> Unable to calculate
>
> v4.4.214: Failed to apply! Possible dependencies:
> 36b68aae8e39 ("usb: dwc3: gadget: use link TRB for all endpoint types")
> 4faf75504a7d ("usb: dwc3: gadget: move % operation to increment helpers")
> 53fd88189e08 ("usb: dwc3: gadget: rename busy/free_slot to trb_enqueue/dequeue")
> 5ee85d890f8d ("usb: dwc3: gadget: split __dwc3_gadget_kick_transfer()")
> 70fdb273db37 ("usb: dwc3: get rid of DWC3_TRB_MASK")
> 8495036e986b ("usb: dwc3: increase maximum number of TRBs per endpoint")
> c4233573f6ee ("usb: dwc3: gadget: prepare TRBs on update transfers too")
> e901aa159dac ("usb: dwc3: gadget: fix endpoint renaming")
> ef966b9d3353 ("usb: dwc3: gadget: add trb enqueue/dequeue helpers")
>
>
> NOTE: The patch will not be queued to stable trees until it is upstream.
>
> How should we proceed with this patch?
Sorry, I only see this change as critical for 4.20+ kernels (where it
started biting folks), but I'd defer to Felipe if he'd like to see it
go any further back.
thanks
-john
The patch titled
Subject: mm, hotplug: fix page online with DEBUG_PAGEALLOC compiled but not enabled
has been added to the -mm tree. Its filename is
mm-hotplug-fix-page-online-with-debug_pagealloc-compiled-but-not-enabled.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/mm-hotplug-fix-page-online-with-de…
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/mm-hotplug-fix-page-online-with-de…
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Vlastimil Babka <vbabka(a)suse.cz>
Subject: mm, hotplug: fix page online with DEBUG_PAGEALLOC compiled but not enabled
Commit cd02cf1aceea ("mm/hotplug: fix an imbalance with DEBUG_PAGEALLOC")
fixed memory hotplug with debug_pagealloc enabled, where onlining a page
goes through page freeing, which removes the direct mapping. Some arches
don't like when the page is not mapped in the first place, so
generic_online_page() maps it first. This is somewhat wasteful, but
better than special casing page freeing fast paths.
The commit however missed that DEBUG_PAGEALLOC configured doesn't mean
it's actually enabled. One has to test debug_pagealloc_enabled() since
031bc5743f15 ("mm/debug-pagealloc: make debug-pagealloc boottime
configurable"), or alternatively debug_pagealloc_enabled_static() since
8e57f8acbbd1 ("mm, debug_pagealloc: don't rely on static keys too early"),
but this is not done.
As a result, a s390 kernel with DEBUG_PAGEALLOC configured but not enabled
will crash:
Unable to handle kernel pointer dereference in virtual kernel address space
Failing address: 0000000000000000 TEID: 0000000000000483
Fault in home space mode while using kernel ASCE.
AS:0000001ece13400b R2:000003fff7fd000b R3:000003fff7fcc007 S:000003fff7fd7000 P:000000000000013d
Oops: 0004 ilc:2 [#1] SMP
CPU: 1 PID: 26015 Comm: chmem Kdump: loaded Tainted: GX 5.3.18-5-default #1 SLE15-SP2 (unreleased)
Krnl PSW : 0704e00180000000 0000001ecd281b9e (__kernel_map_pages+0x166/0x188)
R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:2 PM:0 RI:0 EA:3
Krnl GPRS: 0000000000000000 0000000000000800 0000400b00000000 0000000000000100
0000000000000001 0000000000000000 0000000000000002 0000000000000100
0000001ece139230 0000001ecdd98d40 0000400b00000100 0000000000000000
000003ffa17e4000 001fffe0114f7d08 0000001ecd4d93ea 001fffe0114f7b20
Krnl Code: 0000001ecd281b8e: ec17ffff00d8 ahik %r1,%r7,-1
0000001ecd281b94: ec111dbc0355 risbg %r1,%r1,29,188,3
>0000001ecd281b9e: 94fb5006 ni 6(%r5),251
0000001ecd281ba2: 41505008 la %r5,8(%r5)
0000001ecd281ba6: ec51fffc6064 cgrj %r5,%r1,6,1ecd281b9e
0000001ecd281bac: 1a07 ar %r0,%r7
0000001ecd281bae: ec03ff584076 crj %r0,%r3,4,1ecd281a5e
Call Trace:
[<0000001ecd281b9e>] __kernel_map_pages+0x166/0x188
[<0000001ecd4d9516>] online_pages_range+0xf6/0x128
[<0000001ecd2a8186>] walk_system_ram_range+0x7e/0xd8
[<0000001ecda28aae>] online_pages+0x2fe/0x3f0
[<0000001ecd7d02a6>] memory_subsys_online+0x8e/0xc0
[<0000001ecd7add42>] device_online+0x5a/0xc8
[<0000001ecd7d0430>] state_store+0x88/0x118
[<0000001ecd5b9f62>] kernfs_fop_write+0xc2/0x200
[<0000001ecd5064b6>] vfs_write+0x176/0x1e0
[<0000001ecd50676a>] ksys_write+0xa2/0x100
[<0000001ecda315d4>] system_call+0xd8/0x2c8
Fix this by checking debug_pagealloc_enabled_static() before calling
kernel_map_pages(). Backports for kernel before 5.5 should use
debug_pagealloc_enabled() instead. Also add comments.
Link: http://lkml.kernel.org/r/20200224094651.18257-1-vbabka@suse.cz
Fixes: cd02cf1aceea ("mm/hotplug: fix an imbalance with DEBUG_PAGEALLOC")
Signed-off-by: Vlastimil Babka <vbabka(a)suse.cz>
Reported-by: Gerald Schaefer <gerald.schaefer(a)de.ibm.com>
Reviewed-by: David Hildenbrand <david(a)redhat.com>
Cc: Qian Cai <cai(a)lca.pw>
Cc: Joonsoo Kim <iamjoonsoo.kim(a)lge.com>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
include/linux/mm.h | 4 ++++
mm/memory_hotplug.c | 8 +++++++-
2 files changed, 11 insertions(+), 1 deletion(-)
--- a/include/linux/mm.h~mm-hotplug-fix-page-online-with-debug_pagealloc-compiled-but-not-enabled
+++ a/include/linux/mm.h
@@ -2715,6 +2715,10 @@ static inline bool debug_pagealloc_enabl
#if defined(CONFIG_DEBUG_PAGEALLOC) || defined(CONFIG_ARCH_HAS_SET_DIRECT_MAP)
extern void __kernel_map_pages(struct page *page, int numpages, int enable);
+/*
+ * When called in DEBUG_PAGEALLOC context, the call should most likely be
+ * guarded by debug_pagealloc_enabled() or debug_pagealloc_enabled_static()
+ */
static inline void
kernel_map_pages(struct page *page, int numpages, int enable)
{
--- a/mm/memory_hotplug.c~mm-hotplug-fix-page-online-with-debug_pagealloc-compiled-but-not-enabled
+++ a/mm/memory_hotplug.c
@@ -574,7 +574,13 @@ EXPORT_SYMBOL_GPL(restore_online_page_ca
void generic_online_page(struct page *page, unsigned int order)
{
- kernel_map_pages(page, 1 << order, 1);
+ /*
+ * Freeing the page with debug_pagealloc enabled will try to unmap it,
+ * so we should map it first. This is better than introducing a special
+ * case in page freeing fast path.
+ */
+ if (debug_pagealloc_enabled_static())
+ kernel_map_pages(page, 1 << order, 1);
__free_pages_core(page, order);
totalram_pages_add(1UL << order);
#ifdef CONFIG_HIGHMEM
_
Patches currently in -mm which might be from vbabka(a)suse.cz are
mm-hotplug-fix-page-online-with-debug_pagealloc-compiled-but-not-enabled.patch