The patch below does not apply to the 4.19-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-4.19.y
git checkout FETCH_HEAD
git cherry-pick -x 9972605a238339b85bd16b084eed5f18414d22db
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2024081232-delivery-pushover-0bb3@gregkh' --subject-prefix 'PATCH 4.19.y' HEAD^..
Possible dependencies:
9972605a2383 ("memcg: protect concurrent access to mem_cgroup_idr")
6f0df8e16eb5 ("memcontrol: ensure memcg acquired by id is properly set up")
e4dde56cd208 ("mm: multi-gen LRU: per-node lru_gen_folio lists")
7348cc91821b ("mm: multi-gen LRU: remove aging fairness safeguard")
a579086c99ed ("mm: multi-gen LRU: remove eviction fairness safeguard")
adb8213014b2 ("mm: memcg: fix stale protection of reclaim target memcg")
57e9cc50f4dd ("mm: vmscan: split khugepaged stats from direct reclaim stats")
e4fea72b1438 ("mglru: mm/vmscan.c: fix imprecise comments")
d396def5d86d ("memcg: rearrange code")
410f8e82689e ("memcg: extract memcg_vmstats from struct mem_cgroup")
d6c3af7d8a2b ("mm: multi-gen LRU: debugfs interface")
1332a809d95a ("mm: multi-gen LRU: thrashing prevention")
354ed5974429 ("mm: multi-gen LRU: kill switch")
f76c83378851 ("mm: multi-gen LRU: optimize multiple memcgs")
bd74fdaea146 ("mm: multi-gen LRU: support page table walks")
018ee47f1489 ("mm: multi-gen LRU: exploit locality in rmap")
ac35a4902374 ("mm: multi-gen LRU: minimal implementation")
ec1c86b25f4b ("mm: multi-gen LRU: groundwork")
f1e1a7be4718 ("mm/vmscan.c: refactor shrink_node()")
d3629af59f41 ("mm/vmscan: make the annotations of refaults code at the right place")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 9972605a238339b85bd16b084eed5f18414d22db Mon Sep 17 00:00:00 2001
From: Shakeel Butt <shakeel.butt(a)linux.dev>
Date: Fri, 2 Aug 2024 16:58:22 -0700
Subject: [PATCH] memcg: protect concurrent access to mem_cgroup_idr
Commit 73f576c04b94 ("mm: memcontrol: fix cgroup creation failure after
many small jobs") decoupled the memcg IDs from the CSS ID space to fix the
cgroup creation failures. It introduced IDR to maintain the memcg ID
space. The IDR depends on external synchronization mechanisms for
modifications. For the mem_cgroup_idr, the idr_alloc() and idr_replace()
happen within css callback and thus are protected through cgroup_mutex
from concurrent modifications. However idr_remove() for mem_cgroup_idr
was not protected against concurrency and can be run concurrently for
different memcgs when they hit their refcnt to zero. Fix that.
We have been seeing list_lru based kernel crashes at a low frequency in
our fleet for a long time. These crashes were in different part of
list_lru code including list_lru_add(), list_lru_del() and reparenting
code. Upon further inspection, it looked like for a given object (dentry
and inode), the super_block's list_lru didn't have list_lru_one for the
memcg of that object. The initial suspicions were either the object is
not allocated through kmem_cache_alloc_lru() or somehow
memcg_list_lru_alloc() failed to allocate list_lru_one() for a memcg but
returned success. No evidence were found for these cases.
Looking more deeply, we started seeing situations where valid memcg's id
is not present in mem_cgroup_idr and in some cases multiple valid memcgs
have same id and mem_cgroup_idr is pointing to one of them. So, the most
reasonable explanation is that these situations can happen due to race
between multiple idr_remove() calls or race between
idr_alloc()/idr_replace() and idr_remove(). These races are causing
multiple memcgs to acquire the same ID and then offlining of one of them
would cleanup list_lrus on the system for all of them. Later access from
other memcgs to the list_lru cause crashes due to missing list_lru_one.
Link: https://lkml.kernel.org/r/20240802235822.1830976-1-shakeel.butt@linux.dev
Fixes: 73f576c04b94 ("mm: memcontrol: fix cgroup creation failure after many small jobs")
Signed-off-by: Shakeel Butt <shakeel.butt(a)linux.dev>
Acked-by: Muchun Song <muchun.song(a)linux.dev>
Reviewed-by: Roman Gushchin <roman.gushchin(a)linux.dev>
Acked-by: Johannes Weiner <hannes(a)cmpxchg.org>
Cc: Michal Hocko <mhocko(a)suse.com>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 960371788687..f29157288b7d 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -3386,11 +3386,28 @@ static void memcg_wb_domain_size_changed(struct mem_cgroup *memcg)
#define MEM_CGROUP_ID_MAX ((1UL << MEM_CGROUP_ID_SHIFT) - 1)
static DEFINE_IDR(mem_cgroup_idr);
+static DEFINE_SPINLOCK(memcg_idr_lock);
+
+static int mem_cgroup_alloc_id(void)
+{
+ int ret;
+
+ idr_preload(GFP_KERNEL);
+ spin_lock(&memcg_idr_lock);
+ ret = idr_alloc(&mem_cgroup_idr, NULL, 1, MEM_CGROUP_ID_MAX + 1,
+ GFP_NOWAIT);
+ spin_unlock(&memcg_idr_lock);
+ idr_preload_end();
+ return ret;
+}
static void mem_cgroup_id_remove(struct mem_cgroup *memcg)
{
if (memcg->id.id > 0) {
+ spin_lock(&memcg_idr_lock);
idr_remove(&mem_cgroup_idr, memcg->id.id);
+ spin_unlock(&memcg_idr_lock);
+
memcg->id.id = 0;
}
}
@@ -3524,8 +3541,7 @@ static struct mem_cgroup *mem_cgroup_alloc(struct mem_cgroup *parent)
if (!memcg)
return ERR_PTR(error);
- memcg->id.id = idr_alloc(&mem_cgroup_idr, NULL,
- 1, MEM_CGROUP_ID_MAX + 1, GFP_KERNEL);
+ memcg->id.id = mem_cgroup_alloc_id();
if (memcg->id.id < 0) {
error = memcg->id.id;
goto fail;
@@ -3667,7 +3683,9 @@ static int mem_cgroup_css_online(struct cgroup_subsys_state *css)
* publish it here at the end of onlining. This matches the
* regular ID destruction during offlining.
*/
+ spin_lock(&memcg_idr_lock);
idr_replace(&mem_cgroup_idr, memcg, memcg->id.id);
+ spin_unlock(&memcg_idr_lock);
return 0;
offline_kmem:
The patch below does not apply to the 5.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.4.y
git checkout FETCH_HEAD
git cherry-pick -x 9972605a238339b85bd16b084eed5f18414d22db
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2024081223-bartender-relic-1b52@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^..
Possible dependencies:
9972605a2383 ("memcg: protect concurrent access to mem_cgroup_idr")
6f0df8e16eb5 ("memcontrol: ensure memcg acquired by id is properly set up")
e4dde56cd208 ("mm: multi-gen LRU: per-node lru_gen_folio lists")
7348cc91821b ("mm: multi-gen LRU: remove aging fairness safeguard")
a579086c99ed ("mm: multi-gen LRU: remove eviction fairness safeguard")
adb8213014b2 ("mm: memcg: fix stale protection of reclaim target memcg")
57e9cc50f4dd ("mm: vmscan: split khugepaged stats from direct reclaim stats")
e4fea72b1438 ("mglru: mm/vmscan.c: fix imprecise comments")
d396def5d86d ("memcg: rearrange code")
410f8e82689e ("memcg: extract memcg_vmstats from struct mem_cgroup")
d6c3af7d8a2b ("mm: multi-gen LRU: debugfs interface")
1332a809d95a ("mm: multi-gen LRU: thrashing prevention")
354ed5974429 ("mm: multi-gen LRU: kill switch")
f76c83378851 ("mm: multi-gen LRU: optimize multiple memcgs")
bd74fdaea146 ("mm: multi-gen LRU: support page table walks")
018ee47f1489 ("mm: multi-gen LRU: exploit locality in rmap")
ac35a4902374 ("mm: multi-gen LRU: minimal implementation")
ec1c86b25f4b ("mm: multi-gen LRU: groundwork")
f1e1a7be4718 ("mm/vmscan.c: refactor shrink_node()")
d3629af59f41 ("mm/vmscan: make the annotations of refaults code at the right place")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 9972605a238339b85bd16b084eed5f18414d22db Mon Sep 17 00:00:00 2001
From: Shakeel Butt <shakeel.butt(a)linux.dev>
Date: Fri, 2 Aug 2024 16:58:22 -0700
Subject: [PATCH] memcg: protect concurrent access to mem_cgroup_idr
Commit 73f576c04b94 ("mm: memcontrol: fix cgroup creation failure after
many small jobs") decoupled the memcg IDs from the CSS ID space to fix the
cgroup creation failures. It introduced IDR to maintain the memcg ID
space. The IDR depends on external synchronization mechanisms for
modifications. For the mem_cgroup_idr, the idr_alloc() and idr_replace()
happen within css callback and thus are protected through cgroup_mutex
from concurrent modifications. However idr_remove() for mem_cgroup_idr
was not protected against concurrency and can be run concurrently for
different memcgs when they hit their refcnt to zero. Fix that.
We have been seeing list_lru based kernel crashes at a low frequency in
our fleet for a long time. These crashes were in different part of
list_lru code including list_lru_add(), list_lru_del() and reparenting
code. Upon further inspection, it looked like for a given object (dentry
and inode), the super_block's list_lru didn't have list_lru_one for the
memcg of that object. The initial suspicions were either the object is
not allocated through kmem_cache_alloc_lru() or somehow
memcg_list_lru_alloc() failed to allocate list_lru_one() for a memcg but
returned success. No evidence were found for these cases.
Looking more deeply, we started seeing situations where valid memcg's id
is not present in mem_cgroup_idr and in some cases multiple valid memcgs
have same id and mem_cgroup_idr is pointing to one of them. So, the most
reasonable explanation is that these situations can happen due to race
between multiple idr_remove() calls or race between
idr_alloc()/idr_replace() and idr_remove(). These races are causing
multiple memcgs to acquire the same ID and then offlining of one of them
would cleanup list_lrus on the system for all of them. Later access from
other memcgs to the list_lru cause crashes due to missing list_lru_one.
Link: https://lkml.kernel.org/r/20240802235822.1830976-1-shakeel.butt@linux.dev
Fixes: 73f576c04b94 ("mm: memcontrol: fix cgroup creation failure after many small jobs")
Signed-off-by: Shakeel Butt <shakeel.butt(a)linux.dev>
Acked-by: Muchun Song <muchun.song(a)linux.dev>
Reviewed-by: Roman Gushchin <roman.gushchin(a)linux.dev>
Acked-by: Johannes Weiner <hannes(a)cmpxchg.org>
Cc: Michal Hocko <mhocko(a)suse.com>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 960371788687..f29157288b7d 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -3386,11 +3386,28 @@ static void memcg_wb_domain_size_changed(struct mem_cgroup *memcg)
#define MEM_CGROUP_ID_MAX ((1UL << MEM_CGROUP_ID_SHIFT) - 1)
static DEFINE_IDR(mem_cgroup_idr);
+static DEFINE_SPINLOCK(memcg_idr_lock);
+
+static int mem_cgroup_alloc_id(void)
+{
+ int ret;
+
+ idr_preload(GFP_KERNEL);
+ spin_lock(&memcg_idr_lock);
+ ret = idr_alloc(&mem_cgroup_idr, NULL, 1, MEM_CGROUP_ID_MAX + 1,
+ GFP_NOWAIT);
+ spin_unlock(&memcg_idr_lock);
+ idr_preload_end();
+ return ret;
+}
static void mem_cgroup_id_remove(struct mem_cgroup *memcg)
{
if (memcg->id.id > 0) {
+ spin_lock(&memcg_idr_lock);
idr_remove(&mem_cgroup_idr, memcg->id.id);
+ spin_unlock(&memcg_idr_lock);
+
memcg->id.id = 0;
}
}
@@ -3524,8 +3541,7 @@ static struct mem_cgroup *mem_cgroup_alloc(struct mem_cgroup *parent)
if (!memcg)
return ERR_PTR(error);
- memcg->id.id = idr_alloc(&mem_cgroup_idr, NULL,
- 1, MEM_CGROUP_ID_MAX + 1, GFP_KERNEL);
+ memcg->id.id = mem_cgroup_alloc_id();
if (memcg->id.id < 0) {
error = memcg->id.id;
goto fail;
@@ -3667,7 +3683,9 @@ static int mem_cgroup_css_online(struct cgroup_subsys_state *css)
* publish it here at the end of onlining. This matches the
* regular ID destruction during offlining.
*/
+ spin_lock(&memcg_idr_lock);
idr_replace(&mem_cgroup_idr, memcg, memcg->id.id);
+ spin_unlock(&memcg_idr_lock);
return 0;
offline_kmem:
The patch below does not apply to the 4.19-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-4.19.y
git checkout FETCH_HEAD
git cherry-pick -x 7d3b793faaab1305994ce568b59d61927235f57b
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2024081221-mumbo-smugly-ba61@gregkh' --subject-prefix 'PATCH 4.19.y' HEAD^..
Possible dependencies:
7d3b793faaab ("serial: sc16is7xx: fix invalid FIFO access with special register set")
8492bd91aa05 ("serial: sc16is7xx: fix bug in sc16is7xx_set_baud() when using prescaler")
0c84bea0cabc ("serial: sc16is7xx: refactor EFR lock")
2de8a1b46756 ("serial: sc16is7xx: reorder code to remove prototype declarations")
2e57cefc4477 ("serial: sc16is7xx: replace hardcoded divisor value with BIT() macro")
4409df5866b7 ("serial: sc16is7xx: change EFR lock to operate on each channels")
3837a0379533 ("serial: sc16is7xx: improve regmap debugfs by using one regmap per port")
22a048b07493 ("serial: sc16is7xx: remove unused to_sc16is7xx_port macro")
b4a778303ea0 ("serial: sc16is7xx: add missing support for rs485 devicetree properties")
049994292834 ("serial: sc16is7xx: fix regression with GPIO configuration")
dabc54a45711 ("serial: sc16is7xx: remove obsolete out_thread label")
c8f71b49ee4d ("serial: sc16is7xx: setup GPIO controller later in probe")
267913ecf737 ("serial: sc16is7xx: Fill in rs485_supported")
6e124e58ae2e ("sc16is7xx: Set AUTOCTS and AUTORTS bits")
21144bab4f11 ("sc16is7xx: Handle modem status lines")
cc4c1d05eb10 ("sc16is7xx: Properly resume TX after stop")
d4ab5487cc77 ("Merge 5.17-rc6 into tty-next")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 7d3b793faaab1305994ce568b59d61927235f57b Mon Sep 17 00:00:00 2001
From: Hugo Villeneuve <hvilleneuve(a)dimonoff.com>
Date: Tue, 23 Jul 2024 08:53:01 -0400
Subject: [PATCH] serial: sc16is7xx: fix invalid FIFO access with special
register set
When enabling access to the special register set, Receiver time-out and
RHR interrupts can happen. In this case, the IRQ handler will try to read
from the FIFO thru the RHR register at address 0x00, but address 0x00 is
mapped to DLL register, resulting in erroneous FIFO reading.
Call graph example:
sc16is7xx_startup(): entry
sc16is7xx_ms_proc(): entry
sc16is7xx_set_termios(): entry
sc16is7xx_set_baud(): DLH/DLL = $009C --> access special register set
sc16is7xx_port_irq() entry --> IIR is 0x0C
sc16is7xx_handle_rx() entry
sc16is7xx_fifo_read(): --> unable to access FIFO (RHR) because it is
mapped to DLL (LCR=LCR_CONF_MODE_A)
sc16is7xx_set_baud(): exit --> Restore access to general register set
Fix the problem by claiming the efr_lock mutex when accessing the Special
register set.
Fixes: dfeae619d781 ("serial: sc16is7xx")
Cc: stable(a)vger.kernel.org
Signed-off-by: Hugo Villeneuve <hvilleneuve(a)dimonoff.com>
Link: https://lore.kernel.org/r/20240723125302.1305372-3-hugo@hugovil.com
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
diff --git a/drivers/tty/serial/sc16is7xx.c b/drivers/tty/serial/sc16is7xx.c
index 58696e05492c..b4c1798a1df2 100644
--- a/drivers/tty/serial/sc16is7xx.c
+++ b/drivers/tty/serial/sc16is7xx.c
@@ -592,6 +592,8 @@ static int sc16is7xx_set_baud(struct uart_port *port, int baud)
SC16IS7XX_MCR_CLKSEL_BIT,
prescaler == 1 ? 0 : SC16IS7XX_MCR_CLKSEL_BIT);
+ mutex_lock(&one->efr_lock);
+
/* Backup LCR and access special register set (DLL/DLH) */
lcr = sc16is7xx_port_read(port, SC16IS7XX_LCR_REG);
sc16is7xx_port_write(port, SC16IS7XX_LCR_REG,
@@ -606,6 +608,8 @@ static int sc16is7xx_set_baud(struct uart_port *port, int baud)
/* Restore LCR and access to general register set */
sc16is7xx_port_write(port, SC16IS7XX_LCR_REG, lcr);
+ mutex_unlock(&one->efr_lock);
+
return DIV_ROUND_CLOSEST((clk / prescaler) / 16, div);
}
The patch below does not apply to the 5.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.4.y
git checkout FETCH_HEAD
git cherry-pick -x 7d3b793faaab1305994ce568b59d61927235f57b
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2024081216-unreal-cape-7729@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^..
Possible dependencies:
7d3b793faaab ("serial: sc16is7xx: fix invalid FIFO access with special register set")
8492bd91aa05 ("serial: sc16is7xx: fix bug in sc16is7xx_set_baud() when using prescaler")
0c84bea0cabc ("serial: sc16is7xx: refactor EFR lock")
2de8a1b46756 ("serial: sc16is7xx: reorder code to remove prototype declarations")
2e57cefc4477 ("serial: sc16is7xx: replace hardcoded divisor value with BIT() macro")
4409df5866b7 ("serial: sc16is7xx: change EFR lock to operate on each channels")
3837a0379533 ("serial: sc16is7xx: improve regmap debugfs by using one regmap per port")
22a048b07493 ("serial: sc16is7xx: remove unused to_sc16is7xx_port macro")
b4a778303ea0 ("serial: sc16is7xx: add missing support for rs485 devicetree properties")
049994292834 ("serial: sc16is7xx: fix regression with GPIO configuration")
dabc54a45711 ("serial: sc16is7xx: remove obsolete out_thread label")
c8f71b49ee4d ("serial: sc16is7xx: setup GPIO controller later in probe")
267913ecf737 ("serial: sc16is7xx: Fill in rs485_supported")
6e124e58ae2e ("sc16is7xx: Set AUTOCTS and AUTORTS bits")
21144bab4f11 ("sc16is7xx: Handle modem status lines")
cc4c1d05eb10 ("sc16is7xx: Properly resume TX after stop")
d4ab5487cc77 ("Merge 5.17-rc6 into tty-next")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 7d3b793faaab1305994ce568b59d61927235f57b Mon Sep 17 00:00:00 2001
From: Hugo Villeneuve <hvilleneuve(a)dimonoff.com>
Date: Tue, 23 Jul 2024 08:53:01 -0400
Subject: [PATCH] serial: sc16is7xx: fix invalid FIFO access with special
register set
When enabling access to the special register set, Receiver time-out and
RHR interrupts can happen. In this case, the IRQ handler will try to read
from the FIFO thru the RHR register at address 0x00, but address 0x00 is
mapped to DLL register, resulting in erroneous FIFO reading.
Call graph example:
sc16is7xx_startup(): entry
sc16is7xx_ms_proc(): entry
sc16is7xx_set_termios(): entry
sc16is7xx_set_baud(): DLH/DLL = $009C --> access special register set
sc16is7xx_port_irq() entry --> IIR is 0x0C
sc16is7xx_handle_rx() entry
sc16is7xx_fifo_read(): --> unable to access FIFO (RHR) because it is
mapped to DLL (LCR=LCR_CONF_MODE_A)
sc16is7xx_set_baud(): exit --> Restore access to general register set
Fix the problem by claiming the efr_lock mutex when accessing the Special
register set.
Fixes: dfeae619d781 ("serial: sc16is7xx")
Cc: stable(a)vger.kernel.org
Signed-off-by: Hugo Villeneuve <hvilleneuve(a)dimonoff.com>
Link: https://lore.kernel.org/r/20240723125302.1305372-3-hugo@hugovil.com
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
diff --git a/drivers/tty/serial/sc16is7xx.c b/drivers/tty/serial/sc16is7xx.c
index 58696e05492c..b4c1798a1df2 100644
--- a/drivers/tty/serial/sc16is7xx.c
+++ b/drivers/tty/serial/sc16is7xx.c
@@ -592,6 +592,8 @@ static int sc16is7xx_set_baud(struct uart_port *port, int baud)
SC16IS7XX_MCR_CLKSEL_BIT,
prescaler == 1 ? 0 : SC16IS7XX_MCR_CLKSEL_BIT);
+ mutex_lock(&one->efr_lock);
+
/* Backup LCR and access special register set (DLL/DLH) */
lcr = sc16is7xx_port_read(port, SC16IS7XX_LCR_REG);
sc16is7xx_port_write(port, SC16IS7XX_LCR_REG,
@@ -606,6 +608,8 @@ static int sc16is7xx_set_baud(struct uart_port *port, int baud)
/* Restore LCR and access to general register set */
sc16is7xx_port_write(port, SC16IS7XX_LCR_REG, lcr);
+ mutex_unlock(&one->efr_lock);
+
return DIV_ROUND_CLOSEST((clk / prescaler) / 16, div);
}
The patch below does not apply to the 5.10-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.10.y
git checkout FETCH_HEAD
git cherry-pick -x 7d3b793faaab1305994ce568b59d61927235f57b
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2024081212-walnut-aloof-2d42@gregkh' --subject-prefix 'PATCH 5.10.y' HEAD^..
Possible dependencies:
7d3b793faaab ("serial: sc16is7xx: fix invalid FIFO access with special register set")
8492bd91aa05 ("serial: sc16is7xx: fix bug in sc16is7xx_set_baud() when using prescaler")
0c84bea0cabc ("serial: sc16is7xx: refactor EFR lock")
2de8a1b46756 ("serial: sc16is7xx: reorder code to remove prototype declarations")
2e57cefc4477 ("serial: sc16is7xx: replace hardcoded divisor value with BIT() macro")
4409df5866b7 ("serial: sc16is7xx: change EFR lock to operate on each channels")
3837a0379533 ("serial: sc16is7xx: improve regmap debugfs by using one regmap per port")
22a048b07493 ("serial: sc16is7xx: remove unused to_sc16is7xx_port macro")
b4a778303ea0 ("serial: sc16is7xx: add missing support for rs485 devicetree properties")
049994292834 ("serial: sc16is7xx: fix regression with GPIO configuration")
dabc54a45711 ("serial: sc16is7xx: remove obsolete out_thread label")
c8f71b49ee4d ("serial: sc16is7xx: setup GPIO controller later in probe")
267913ecf737 ("serial: sc16is7xx: Fill in rs485_supported")
6e124e58ae2e ("sc16is7xx: Set AUTOCTS and AUTORTS bits")
21144bab4f11 ("sc16is7xx: Handle modem status lines")
cc4c1d05eb10 ("sc16is7xx: Properly resume TX after stop")
d4ab5487cc77 ("Merge 5.17-rc6 into tty-next")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 7d3b793faaab1305994ce568b59d61927235f57b Mon Sep 17 00:00:00 2001
From: Hugo Villeneuve <hvilleneuve(a)dimonoff.com>
Date: Tue, 23 Jul 2024 08:53:01 -0400
Subject: [PATCH] serial: sc16is7xx: fix invalid FIFO access with special
register set
When enabling access to the special register set, Receiver time-out and
RHR interrupts can happen. In this case, the IRQ handler will try to read
from the FIFO thru the RHR register at address 0x00, but address 0x00 is
mapped to DLL register, resulting in erroneous FIFO reading.
Call graph example:
sc16is7xx_startup(): entry
sc16is7xx_ms_proc(): entry
sc16is7xx_set_termios(): entry
sc16is7xx_set_baud(): DLH/DLL = $009C --> access special register set
sc16is7xx_port_irq() entry --> IIR is 0x0C
sc16is7xx_handle_rx() entry
sc16is7xx_fifo_read(): --> unable to access FIFO (RHR) because it is
mapped to DLL (LCR=LCR_CONF_MODE_A)
sc16is7xx_set_baud(): exit --> Restore access to general register set
Fix the problem by claiming the efr_lock mutex when accessing the Special
register set.
Fixes: dfeae619d781 ("serial: sc16is7xx")
Cc: stable(a)vger.kernel.org
Signed-off-by: Hugo Villeneuve <hvilleneuve(a)dimonoff.com>
Link: https://lore.kernel.org/r/20240723125302.1305372-3-hugo@hugovil.com
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
diff --git a/drivers/tty/serial/sc16is7xx.c b/drivers/tty/serial/sc16is7xx.c
index 58696e05492c..b4c1798a1df2 100644
--- a/drivers/tty/serial/sc16is7xx.c
+++ b/drivers/tty/serial/sc16is7xx.c
@@ -592,6 +592,8 @@ static int sc16is7xx_set_baud(struct uart_port *port, int baud)
SC16IS7XX_MCR_CLKSEL_BIT,
prescaler == 1 ? 0 : SC16IS7XX_MCR_CLKSEL_BIT);
+ mutex_lock(&one->efr_lock);
+
/* Backup LCR and access special register set (DLL/DLH) */
lcr = sc16is7xx_port_read(port, SC16IS7XX_LCR_REG);
sc16is7xx_port_write(port, SC16IS7XX_LCR_REG,
@@ -606,6 +608,8 @@ static int sc16is7xx_set_baud(struct uart_port *port, int baud)
/* Restore LCR and access to general register set */
sc16is7xx_port_write(port, SC16IS7XX_LCR_REG, lcr);
+ mutex_unlock(&one->efr_lock);
+
return DIV_ROUND_CLOSEST((clk / prescaler) / 16, div);
}
The patch below does not apply to the 5.15-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y
git checkout FETCH_HEAD
git cherry-pick -x 7d3b793faaab1305994ce568b59d61927235f57b
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2024081208-geometry-thread-d393@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..
Possible dependencies:
7d3b793faaab ("serial: sc16is7xx: fix invalid FIFO access with special register set")
8492bd91aa05 ("serial: sc16is7xx: fix bug in sc16is7xx_set_baud() when using prescaler")
0c84bea0cabc ("serial: sc16is7xx: refactor EFR lock")
2de8a1b46756 ("serial: sc16is7xx: reorder code to remove prototype declarations")
2e57cefc4477 ("serial: sc16is7xx: replace hardcoded divisor value with BIT() macro")
4409df5866b7 ("serial: sc16is7xx: change EFR lock to operate on each channels")
3837a0379533 ("serial: sc16is7xx: improve regmap debugfs by using one regmap per port")
22a048b07493 ("serial: sc16is7xx: remove unused to_sc16is7xx_port macro")
b4a778303ea0 ("serial: sc16is7xx: add missing support for rs485 devicetree properties")
049994292834 ("serial: sc16is7xx: fix regression with GPIO configuration")
dabc54a45711 ("serial: sc16is7xx: remove obsolete out_thread label")
c8f71b49ee4d ("serial: sc16is7xx: setup GPIO controller later in probe")
267913ecf737 ("serial: sc16is7xx: Fill in rs485_supported")
6e124e58ae2e ("sc16is7xx: Set AUTOCTS and AUTORTS bits")
21144bab4f11 ("sc16is7xx: Handle modem status lines")
cc4c1d05eb10 ("sc16is7xx: Properly resume TX after stop")
d4ab5487cc77 ("Merge 5.17-rc6 into tty-next")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 7d3b793faaab1305994ce568b59d61927235f57b Mon Sep 17 00:00:00 2001
From: Hugo Villeneuve <hvilleneuve(a)dimonoff.com>
Date: Tue, 23 Jul 2024 08:53:01 -0400
Subject: [PATCH] serial: sc16is7xx: fix invalid FIFO access with special
register set
When enabling access to the special register set, Receiver time-out and
RHR interrupts can happen. In this case, the IRQ handler will try to read
from the FIFO thru the RHR register at address 0x00, but address 0x00 is
mapped to DLL register, resulting in erroneous FIFO reading.
Call graph example:
sc16is7xx_startup(): entry
sc16is7xx_ms_proc(): entry
sc16is7xx_set_termios(): entry
sc16is7xx_set_baud(): DLH/DLL = $009C --> access special register set
sc16is7xx_port_irq() entry --> IIR is 0x0C
sc16is7xx_handle_rx() entry
sc16is7xx_fifo_read(): --> unable to access FIFO (RHR) because it is
mapped to DLL (LCR=LCR_CONF_MODE_A)
sc16is7xx_set_baud(): exit --> Restore access to general register set
Fix the problem by claiming the efr_lock mutex when accessing the Special
register set.
Fixes: dfeae619d781 ("serial: sc16is7xx")
Cc: stable(a)vger.kernel.org
Signed-off-by: Hugo Villeneuve <hvilleneuve(a)dimonoff.com>
Link: https://lore.kernel.org/r/20240723125302.1305372-3-hugo@hugovil.com
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
diff --git a/drivers/tty/serial/sc16is7xx.c b/drivers/tty/serial/sc16is7xx.c
index 58696e05492c..b4c1798a1df2 100644
--- a/drivers/tty/serial/sc16is7xx.c
+++ b/drivers/tty/serial/sc16is7xx.c
@@ -592,6 +592,8 @@ static int sc16is7xx_set_baud(struct uart_port *port, int baud)
SC16IS7XX_MCR_CLKSEL_BIT,
prescaler == 1 ? 0 : SC16IS7XX_MCR_CLKSEL_BIT);
+ mutex_lock(&one->efr_lock);
+
/* Backup LCR and access special register set (DLL/DLH) */
lcr = sc16is7xx_port_read(port, SC16IS7XX_LCR_REG);
sc16is7xx_port_write(port, SC16IS7XX_LCR_REG,
@@ -606,6 +608,8 @@ static int sc16is7xx_set_baud(struct uart_port *port, int baud)
/* Restore LCR and access to general register set */
sc16is7xx_port_write(port, SC16IS7XX_LCR_REG, lcr);
+ mutex_unlock(&one->efr_lock);
+
return DIV_ROUND_CLOSEST((clk / prescaler) / 16, div);
}
The patch below does not apply to the 6.1-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y
git checkout FETCH_HEAD
git cherry-pick -x 7d3b793faaab1305994ce568b59d61927235f57b
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2024081204-deserving-flanked-a918@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..
Possible dependencies:
7d3b793faaab ("serial: sc16is7xx: fix invalid FIFO access with special register set")
8492bd91aa05 ("serial: sc16is7xx: fix bug in sc16is7xx_set_baud() when using prescaler")
0c84bea0cabc ("serial: sc16is7xx: refactor EFR lock")
2de8a1b46756 ("serial: sc16is7xx: reorder code to remove prototype declarations")
2e57cefc4477 ("serial: sc16is7xx: replace hardcoded divisor value with BIT() macro")
4409df5866b7 ("serial: sc16is7xx: change EFR lock to operate on each channels")
3837a0379533 ("serial: sc16is7xx: improve regmap debugfs by using one regmap per port")
22a048b07493 ("serial: sc16is7xx: remove unused to_sc16is7xx_port macro")
b4a778303ea0 ("serial: sc16is7xx: add missing support for rs485 devicetree properties")
049994292834 ("serial: sc16is7xx: fix regression with GPIO configuration")
dabc54a45711 ("serial: sc16is7xx: remove obsolete out_thread label")
c8f71b49ee4d ("serial: sc16is7xx: setup GPIO controller later in probe")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 7d3b793faaab1305994ce568b59d61927235f57b Mon Sep 17 00:00:00 2001
From: Hugo Villeneuve <hvilleneuve(a)dimonoff.com>
Date: Tue, 23 Jul 2024 08:53:01 -0400
Subject: [PATCH] serial: sc16is7xx: fix invalid FIFO access with special
register set
When enabling access to the special register set, Receiver time-out and
RHR interrupts can happen. In this case, the IRQ handler will try to read
from the FIFO thru the RHR register at address 0x00, but address 0x00 is
mapped to DLL register, resulting in erroneous FIFO reading.
Call graph example:
sc16is7xx_startup(): entry
sc16is7xx_ms_proc(): entry
sc16is7xx_set_termios(): entry
sc16is7xx_set_baud(): DLH/DLL = $009C --> access special register set
sc16is7xx_port_irq() entry --> IIR is 0x0C
sc16is7xx_handle_rx() entry
sc16is7xx_fifo_read(): --> unable to access FIFO (RHR) because it is
mapped to DLL (LCR=LCR_CONF_MODE_A)
sc16is7xx_set_baud(): exit --> Restore access to general register set
Fix the problem by claiming the efr_lock mutex when accessing the Special
register set.
Fixes: dfeae619d781 ("serial: sc16is7xx")
Cc: stable(a)vger.kernel.org
Signed-off-by: Hugo Villeneuve <hvilleneuve(a)dimonoff.com>
Link: https://lore.kernel.org/r/20240723125302.1305372-3-hugo@hugovil.com
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
diff --git a/drivers/tty/serial/sc16is7xx.c b/drivers/tty/serial/sc16is7xx.c
index 58696e05492c..b4c1798a1df2 100644
--- a/drivers/tty/serial/sc16is7xx.c
+++ b/drivers/tty/serial/sc16is7xx.c
@@ -592,6 +592,8 @@ static int sc16is7xx_set_baud(struct uart_port *port, int baud)
SC16IS7XX_MCR_CLKSEL_BIT,
prescaler == 1 ? 0 : SC16IS7XX_MCR_CLKSEL_BIT);
+ mutex_lock(&one->efr_lock);
+
/* Backup LCR and access special register set (DLL/DLH) */
lcr = sc16is7xx_port_read(port, SC16IS7XX_LCR_REG);
sc16is7xx_port_write(port, SC16IS7XX_LCR_REG,
@@ -606,6 +608,8 @@ static int sc16is7xx_set_baud(struct uart_port *port, int baud)
/* Restore LCR and access to general register set */
sc16is7xx_port_write(port, SC16IS7XX_LCR_REG, lcr);
+ mutex_unlock(&one->efr_lock);
+
return DIV_ROUND_CLOSEST((clk / prescaler) / 16, div);
}
The patch below does not apply to the 6.6-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y
git checkout FETCH_HEAD
git cherry-pick -x 7d3b793faaab1305994ce568b59d61927235f57b
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2024081200-disorder-styling-e89d@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^..
Possible dependencies:
7d3b793faaab ("serial: sc16is7xx: fix invalid FIFO access with special register set")
8492bd91aa05 ("serial: sc16is7xx: fix bug in sc16is7xx_set_baud() when using prescaler")
0c84bea0cabc ("serial: sc16is7xx: refactor EFR lock")
2de8a1b46756 ("serial: sc16is7xx: reorder code to remove prototype declarations")
2e57cefc4477 ("serial: sc16is7xx: replace hardcoded divisor value with BIT() macro")
4409df5866b7 ("serial: sc16is7xx: change EFR lock to operate on each channels")
3837a0379533 ("serial: sc16is7xx: improve regmap debugfs by using one regmap per port")
22a048b07493 ("serial: sc16is7xx: remove unused to_sc16is7xx_port macro")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 7d3b793faaab1305994ce568b59d61927235f57b Mon Sep 17 00:00:00 2001
From: Hugo Villeneuve <hvilleneuve(a)dimonoff.com>
Date: Tue, 23 Jul 2024 08:53:01 -0400
Subject: [PATCH] serial: sc16is7xx: fix invalid FIFO access with special
register set
When enabling access to the special register set, Receiver time-out and
RHR interrupts can happen. In this case, the IRQ handler will try to read
from the FIFO thru the RHR register at address 0x00, but address 0x00 is
mapped to DLL register, resulting in erroneous FIFO reading.
Call graph example:
sc16is7xx_startup(): entry
sc16is7xx_ms_proc(): entry
sc16is7xx_set_termios(): entry
sc16is7xx_set_baud(): DLH/DLL = $009C --> access special register set
sc16is7xx_port_irq() entry --> IIR is 0x0C
sc16is7xx_handle_rx() entry
sc16is7xx_fifo_read(): --> unable to access FIFO (RHR) because it is
mapped to DLL (LCR=LCR_CONF_MODE_A)
sc16is7xx_set_baud(): exit --> Restore access to general register set
Fix the problem by claiming the efr_lock mutex when accessing the Special
register set.
Fixes: dfeae619d781 ("serial: sc16is7xx")
Cc: stable(a)vger.kernel.org
Signed-off-by: Hugo Villeneuve <hvilleneuve(a)dimonoff.com>
Link: https://lore.kernel.org/r/20240723125302.1305372-3-hugo@hugovil.com
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
diff --git a/drivers/tty/serial/sc16is7xx.c b/drivers/tty/serial/sc16is7xx.c
index 58696e05492c..b4c1798a1df2 100644
--- a/drivers/tty/serial/sc16is7xx.c
+++ b/drivers/tty/serial/sc16is7xx.c
@@ -592,6 +592,8 @@ static int sc16is7xx_set_baud(struct uart_port *port, int baud)
SC16IS7XX_MCR_CLKSEL_BIT,
prescaler == 1 ? 0 : SC16IS7XX_MCR_CLKSEL_BIT);
+ mutex_lock(&one->efr_lock);
+
/* Backup LCR and access special register set (DLL/DLH) */
lcr = sc16is7xx_port_read(port, SC16IS7XX_LCR_REG);
sc16is7xx_port_write(port, SC16IS7XX_LCR_REG,
@@ -606,6 +608,8 @@ static int sc16is7xx_set_baud(struct uart_port *port, int baud)
/* Restore LCR and access to general register set */
sc16is7xx_port_write(port, SC16IS7XX_LCR_REG, lcr);
+ mutex_unlock(&one->efr_lock);
+
return DIV_ROUND_CLOSEST((clk / prescaler) / 16, div);
}
The patch below does not apply to the 6.6-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y
git checkout FETCH_HEAD
git cherry-pick -x 133f4c00b8b2bfcacead9b81e7e8edfceb4b06c4
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2024081235-guzzler-tubeless-8a2c@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^..
Possible dependencies:
133f4c00b8b2 ("serial: sc16is7xx: fix TX fifo corruption")
1788cf6a91d9 ("tty: serial: switch from circ_buf to kfifo")
f8fef2fa419f ("tty: msm_serial: use dmaengine_prep_slave_sg()")
9054605ab846 ("tty: 8250_omap: use dmaengine_prep_slave_sg()")
8192fabb0db2 ("tty: 8250_dma: use dmaengine_prep_slave_sg()")
3bcb0bf65c2b ("Merge tag 'tty-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 133f4c00b8b2bfcacead9b81e7e8edfceb4b06c4 Mon Sep 17 00:00:00 2001
From: Hugo Villeneuve <hvilleneuve(a)dimonoff.com>
Date: Tue, 23 Jul 2024 08:53:00 -0400
Subject: [PATCH] serial: sc16is7xx: fix TX fifo corruption
Sometimes, when a packet is received on channel A at almost the same time
as a packet is about to be transmitted on channel B, we observe with a
logic analyzer that the received packet on channel A is transmitted on
channel B. In other words, the Tx buffer data on channel B is corrupted
with data from channel A.
The problem appeared since commit 4409df5866b7 ("serial: sc16is7xx: change
EFR lock to operate on each channels"), which changed the EFR locking to
operate on each channel instead of chip-wise.
This commit has introduced a regression, because the EFR lock is used not
only to protect the EFR registers access, but also, in a very obscure and
undocumented way, to protect access to the data buffer, which is shared by
the Tx and Rx handlers, but also by each channel of the IC.
Fix this regression first by switching to kfifo_out_linear_ptr() in
sc16is7xx_handle_tx() to eliminate the need for a shared Rx/Tx buffer.
Secondly, replace the chip-wise Rx buffer with a separate Rx buffer for
each channel.
Fixes: 4409df5866b7 ("serial: sc16is7xx: change EFR lock to operate on each channels")
Cc: stable(a)vger.kernel.org
Signed-off-by: Hugo Villeneuve <hvilleneuve(a)dimonoff.com>
Link: https://lore.kernel.org/r/20240723125302.1305372-2-hugo@hugovil.com
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
diff --git a/drivers/tty/serial/sc16is7xx.c b/drivers/tty/serial/sc16is7xx.c
index c79dcd7c8d1a..58696e05492c 100644
--- a/drivers/tty/serial/sc16is7xx.c
+++ b/drivers/tty/serial/sc16is7xx.c
@@ -327,6 +327,7 @@ struct sc16is7xx_one {
struct kthread_work reg_work;
struct kthread_delayed_work ms_work;
struct sc16is7xx_one_config config;
+ unsigned char buf[SC16IS7XX_FIFO_SIZE]; /* Rx buffer. */
unsigned int old_mctrl;
u8 old_lcr; /* Value before EFR access. */
bool irda_mode;
@@ -340,7 +341,6 @@ struct sc16is7xx_port {
unsigned long gpio_valid_mask;
#endif
u8 mctrl_mask;
- unsigned char buf[SC16IS7XX_FIFO_SIZE];
struct kthread_worker kworker;
struct task_struct *kworker_task;
struct sc16is7xx_one p[];
@@ -612,18 +612,18 @@ static int sc16is7xx_set_baud(struct uart_port *port, int baud)
static void sc16is7xx_handle_rx(struct uart_port *port, unsigned int rxlen,
unsigned int iir)
{
- struct sc16is7xx_port *s = dev_get_drvdata(port->dev);
+ struct sc16is7xx_one *one = to_sc16is7xx_one(port, port);
unsigned int lsr = 0, bytes_read, i;
bool read_lsr = (iir == SC16IS7XX_IIR_RLSE_SRC) ? true : false;
u8 ch, flag;
- if (unlikely(rxlen >= sizeof(s->buf))) {
+ if (unlikely(rxlen >= sizeof(one->buf))) {
dev_warn_ratelimited(port->dev,
"ttySC%i: Possible RX FIFO overrun: %d\n",
port->line, rxlen);
port->icount.buf_overrun++;
/* Ensure sanity of RX level */
- rxlen = sizeof(s->buf);
+ rxlen = sizeof(one->buf);
}
while (rxlen) {
@@ -636,10 +636,10 @@ static void sc16is7xx_handle_rx(struct uart_port *port, unsigned int rxlen,
lsr = 0;
if (read_lsr) {
- s->buf[0] = sc16is7xx_port_read(port, SC16IS7XX_RHR_REG);
+ one->buf[0] = sc16is7xx_port_read(port, SC16IS7XX_RHR_REG);
bytes_read = 1;
} else {
- sc16is7xx_fifo_read(port, s->buf, rxlen);
+ sc16is7xx_fifo_read(port, one->buf, rxlen);
bytes_read = rxlen;
}
@@ -672,7 +672,7 @@ static void sc16is7xx_handle_rx(struct uart_port *port, unsigned int rxlen,
}
for (i = 0; i < bytes_read; ++i) {
- ch = s->buf[i];
+ ch = one->buf[i];
if (uart_handle_sysrq_char(port, ch))
continue;
@@ -690,10 +690,10 @@ static void sc16is7xx_handle_rx(struct uart_port *port, unsigned int rxlen,
static void sc16is7xx_handle_tx(struct uart_port *port)
{
- struct sc16is7xx_port *s = dev_get_drvdata(port->dev);
struct tty_port *tport = &port->state->port;
unsigned long flags;
unsigned int txlen;
+ unsigned char *tail;
if (unlikely(port->x_char)) {
sc16is7xx_port_write(port, SC16IS7XX_THR_REG, port->x_char);
@@ -718,8 +718,9 @@ static void sc16is7xx_handle_tx(struct uart_port *port)
txlen = 0;
}
- txlen = uart_fifo_out(port, s->buf, txlen);
- sc16is7xx_fifo_write(port, s->buf, txlen);
+ txlen = kfifo_out_linear_ptr(&tport->xmit_fifo, &tail, txlen);
+ sc16is7xx_fifo_write(port, tail, txlen);
+ uart_xmit_advance(port, txlen);
uart_port_lock_irqsave(port, &flags);
if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS)
The patch below does not apply to the 6.1-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y
git checkout FETCH_HEAD
git cherry-pick -x 133f4c00b8b2bfcacead9b81e7e8edfceb4b06c4
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2024081230-glance-tamale-974a@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..
Possible dependencies:
133f4c00b8b2 ("serial: sc16is7xx: fix TX fifo corruption")
1788cf6a91d9 ("tty: serial: switch from circ_buf to kfifo")
f8fef2fa419f ("tty: msm_serial: use dmaengine_prep_slave_sg()")
9054605ab846 ("tty: 8250_omap: use dmaengine_prep_slave_sg()")
8192fabb0db2 ("tty: 8250_dma: use dmaengine_prep_slave_sg()")
3bcb0bf65c2b ("Merge tag 'tty-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 133f4c00b8b2bfcacead9b81e7e8edfceb4b06c4 Mon Sep 17 00:00:00 2001
From: Hugo Villeneuve <hvilleneuve(a)dimonoff.com>
Date: Tue, 23 Jul 2024 08:53:00 -0400
Subject: [PATCH] serial: sc16is7xx: fix TX fifo corruption
Sometimes, when a packet is received on channel A at almost the same time
as a packet is about to be transmitted on channel B, we observe with a
logic analyzer that the received packet on channel A is transmitted on
channel B. In other words, the Tx buffer data on channel B is corrupted
with data from channel A.
The problem appeared since commit 4409df5866b7 ("serial: sc16is7xx: change
EFR lock to operate on each channels"), which changed the EFR locking to
operate on each channel instead of chip-wise.
This commit has introduced a regression, because the EFR lock is used not
only to protect the EFR registers access, but also, in a very obscure and
undocumented way, to protect access to the data buffer, which is shared by
the Tx and Rx handlers, but also by each channel of the IC.
Fix this regression first by switching to kfifo_out_linear_ptr() in
sc16is7xx_handle_tx() to eliminate the need for a shared Rx/Tx buffer.
Secondly, replace the chip-wise Rx buffer with a separate Rx buffer for
each channel.
Fixes: 4409df5866b7 ("serial: sc16is7xx: change EFR lock to operate on each channels")
Cc: stable(a)vger.kernel.org
Signed-off-by: Hugo Villeneuve <hvilleneuve(a)dimonoff.com>
Link: https://lore.kernel.org/r/20240723125302.1305372-2-hugo@hugovil.com
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
diff --git a/drivers/tty/serial/sc16is7xx.c b/drivers/tty/serial/sc16is7xx.c
index c79dcd7c8d1a..58696e05492c 100644
--- a/drivers/tty/serial/sc16is7xx.c
+++ b/drivers/tty/serial/sc16is7xx.c
@@ -327,6 +327,7 @@ struct sc16is7xx_one {
struct kthread_work reg_work;
struct kthread_delayed_work ms_work;
struct sc16is7xx_one_config config;
+ unsigned char buf[SC16IS7XX_FIFO_SIZE]; /* Rx buffer. */
unsigned int old_mctrl;
u8 old_lcr; /* Value before EFR access. */
bool irda_mode;
@@ -340,7 +341,6 @@ struct sc16is7xx_port {
unsigned long gpio_valid_mask;
#endif
u8 mctrl_mask;
- unsigned char buf[SC16IS7XX_FIFO_SIZE];
struct kthread_worker kworker;
struct task_struct *kworker_task;
struct sc16is7xx_one p[];
@@ -612,18 +612,18 @@ static int sc16is7xx_set_baud(struct uart_port *port, int baud)
static void sc16is7xx_handle_rx(struct uart_port *port, unsigned int rxlen,
unsigned int iir)
{
- struct sc16is7xx_port *s = dev_get_drvdata(port->dev);
+ struct sc16is7xx_one *one = to_sc16is7xx_one(port, port);
unsigned int lsr = 0, bytes_read, i;
bool read_lsr = (iir == SC16IS7XX_IIR_RLSE_SRC) ? true : false;
u8 ch, flag;
- if (unlikely(rxlen >= sizeof(s->buf))) {
+ if (unlikely(rxlen >= sizeof(one->buf))) {
dev_warn_ratelimited(port->dev,
"ttySC%i: Possible RX FIFO overrun: %d\n",
port->line, rxlen);
port->icount.buf_overrun++;
/* Ensure sanity of RX level */
- rxlen = sizeof(s->buf);
+ rxlen = sizeof(one->buf);
}
while (rxlen) {
@@ -636,10 +636,10 @@ static void sc16is7xx_handle_rx(struct uart_port *port, unsigned int rxlen,
lsr = 0;
if (read_lsr) {
- s->buf[0] = sc16is7xx_port_read(port, SC16IS7XX_RHR_REG);
+ one->buf[0] = sc16is7xx_port_read(port, SC16IS7XX_RHR_REG);
bytes_read = 1;
} else {
- sc16is7xx_fifo_read(port, s->buf, rxlen);
+ sc16is7xx_fifo_read(port, one->buf, rxlen);
bytes_read = rxlen;
}
@@ -672,7 +672,7 @@ static void sc16is7xx_handle_rx(struct uart_port *port, unsigned int rxlen,
}
for (i = 0; i < bytes_read; ++i) {
- ch = s->buf[i];
+ ch = one->buf[i];
if (uart_handle_sysrq_char(port, ch))
continue;
@@ -690,10 +690,10 @@ static void sc16is7xx_handle_rx(struct uart_port *port, unsigned int rxlen,
static void sc16is7xx_handle_tx(struct uart_port *port)
{
- struct sc16is7xx_port *s = dev_get_drvdata(port->dev);
struct tty_port *tport = &port->state->port;
unsigned long flags;
unsigned int txlen;
+ unsigned char *tail;
if (unlikely(port->x_char)) {
sc16is7xx_port_write(port, SC16IS7XX_THR_REG, port->x_char);
@@ -718,8 +718,9 @@ static void sc16is7xx_handle_tx(struct uart_port *port)
txlen = 0;
}
- txlen = uart_fifo_out(port, s->buf, txlen);
- sc16is7xx_fifo_write(port, s->buf, txlen);
+ txlen = kfifo_out_linear_ptr(&tport->xmit_fifo, &tail, txlen);
+ sc16is7xx_fifo_write(port, tail, txlen);
+ uart_xmit_advance(port, txlen);
uart_port_lock_irqsave(port, &flags);
if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS)