Add a helper for enabling link states that can be used in contexts where
a pci_bus_sem read lock is already held (e.g. from pci_walk_bus()).
This helper will be used to fix a couple of potential deadlocks where
the current helper is called with the lock already held, hence the CC
stable tag.
Fixes: f492edb40b54 ("PCI: vmd: Add quirk to configure PCIe ASPM and LTR")
Cc: stable(a)vger.kernel.org # 6.3
Cc: Michael Bottini <michael.a.bottini(a)linux.intel.com>
Cc: David E. Box <david.e.box(a)linux.intel.com>
Signed-off-by: Johan Hovold <johan+linaro(a)kernel.org>
---
drivers/pci/pcie/aspm.c | 53 +++++++++++++++++++++++++++++++----------
include/linux/pci.h | 3 +++
2 files changed, 43 insertions(+), 13 deletions(-)
diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c
index 50b04ae5c394..8cf8cc2d6bba 100644
--- a/drivers/pci/pcie/aspm.c
+++ b/drivers/pci/pcie/aspm.c
@@ -1109,17 +1109,7 @@ int pci_disable_link_state(struct pci_dev *pdev, int state)
}
EXPORT_SYMBOL(pci_disable_link_state);
-/**
- * pci_enable_link_state - Clear and set the default device link state so that
- * the link may be allowed to enter the specified states. Note that if the
- * BIOS didn't grant ASPM control to the OS, this does nothing because we can't
- * touch the LNKCTL register. Also note that this does not enable states
- * disabled by pci_disable_link_state(). Return 0 or a negative errno.
- *
- * @pdev: PCI device
- * @state: Mask of ASPM link states to enable
- */
-int pci_enable_link_state(struct pci_dev *pdev, int state)
+static int __pci_enable_link_state(struct pci_dev *pdev, int state, bool locked)
{
struct pcie_link_state *link = pcie_aspm_get_link(pdev);
@@ -1136,7 +1126,8 @@ int pci_enable_link_state(struct pci_dev *pdev, int state)
return -EPERM;
}
- down_read(&pci_bus_sem);
+ if (!locked)
+ down_read(&pci_bus_sem);
mutex_lock(&aspm_lock);
link->aspm_default = 0;
if (state & PCIE_LINK_STATE_L0S)
@@ -1157,12 +1148,48 @@ int pci_enable_link_state(struct pci_dev *pdev, int state)
link->clkpm_default = (state & PCIE_LINK_STATE_CLKPM) ? 1 : 0;
pcie_set_clkpm(link, policy_to_clkpm_state(link));
mutex_unlock(&aspm_lock);
- up_read(&pci_bus_sem);
+ if (!locked)
+ up_read(&pci_bus_sem);
return 0;
}
+
+/**
+ * pci_enable_link_state - Clear and set the default device link state so that
+ * the link may be allowed to enter the specified states. Note that if the
+ * BIOS didn't grant ASPM control to the OS, this does nothing because we can't
+ * touch the LNKCTL register. Also note that this does not enable states
+ * disabled by pci_disable_link_state(). Return 0 or a negative errno.
+ *
+ * @pdev: PCI device
+ * @state: Mask of ASPM link states to enable
+ */
+int pci_enable_link_state(struct pci_dev *pdev, int state)
+{
+ return __pci_enable_link_state(pdev, state, false);
+}
EXPORT_SYMBOL(pci_enable_link_state);
+/**
+ * pci_enable_link_state - Clear and set the default device link state so that
+ * the link may be allowed to enter the specified states. Note that if the
+ * BIOS didn't grant ASPM control to the OS, this does nothing because we can't
+ * touch the LNKCTL register. Also note that this does not enable states
+ * disabled by pci_disable_link_state(). Return 0 or a negative errno.
+ *
+ * @pdev: PCI device
+ * @state: Mask of ASPM link states to enable
+ *
+ * Context: Caller holds pci_bus_sem read lock.
+ */
+int pci_enable_link_state_locked(struct pci_dev *pdev, int state)
+{
+ lockdep_assert_held_read(&pci_bus_sem);
+
+ return __pci_enable_link_state(pdev, state, true);
+}
+EXPORT_SYMBOL(pci_enable_link_state_locked);
+
static int pcie_aspm_set_policy(const char *val,
const struct kernel_param *kp)
{
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 60ca768bc867..dea043bc1e38 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1829,6 +1829,7 @@ extern bool pcie_ports_native;
int pci_disable_link_state(struct pci_dev *pdev, int state);
int pci_disable_link_state_locked(struct pci_dev *pdev, int state);
int pci_enable_link_state(struct pci_dev *pdev, int state);
+int pci_enable_link_state_locked(struct pci_dev *pdev, int state);
void pcie_no_aspm(void);
bool pcie_aspm_support_enabled(void);
bool pcie_aspm_enabled(struct pci_dev *pdev);
@@ -1839,6 +1840,8 @@ static inline int pci_disable_link_state_locked(struct pci_dev *pdev, int state)
{ return 0; }
static inline int pci_enable_link_state(struct pci_dev *pdev, int state)
{ return 0; }
+static inline int pci_enable_link_state_locked(struct pci_dev *pdev, int state)
+{ return 0; }
static inline void pcie_no_aspm(void) { }
static inline bool pcie_aspm_support_enabled(void) { return false; }
static inline bool pcie_aspm_enabled(struct pci_dev *pdev) { return false; }
--
2.41.0
This is a partial revert of commit 8b3517f88ff2 ("PCI:
loongson: Prevent LS7A MRRS increases") for MIPS based Loongson.
There are many MIPS based Loongson systems in wild that
shipped with firmware which does not set maximum MRRS properly.
Limiting MRRS to 256 for all as MIPS Loongson comes with higher
MRRS support is considered rare.
It must be done at device enablement stage because MRRS setting
may get lost if the parent bridge lost PCI_COMMAND_MASTER, and
we are only sure parent bridge is enabled at this point.
Cc: stable(a)vger.kernel.org
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=217680
Fixes: 8b3517f88ff2 ("PCI: loongson: Prevent LS7A MRRS increases")
Signed-off-by: Jiaxun Yang <jiaxun.yang(a)flygoat.com>
---
v4: Improve commit message
v5:
- Improve commit message and comments.
- Style fix from Huacai's off-list input.
---
drivers/pci/controller/pci-loongson.c | 47 ++++++++++++++++++++++++---
1 file changed, 42 insertions(+), 5 deletions(-)
diff --git a/drivers/pci/controller/pci-loongson.c b/drivers/pci/controller/pci-loongson.c
index d45e7b8dc530..128cc95b236f 100644
--- a/drivers/pci/controller/pci-loongson.c
+++ b/drivers/pci/controller/pci-loongson.c
@@ -80,13 +80,50 @@ DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_LOONGSON,
DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_LOONGSON,
DEV_LS7A_LPC, system_bus_quirk);
+/*
+ * Some Loongson PCIe ports have h/w limitations of maximum read
+ * request size. They can't handle anything larger than this.
+ * Sane firmware will set proper MRRS at boot, so we only need
+ * no_inc_mrrs for bridges. However, some MIPS Loongson firmware
+ * won't set MRRS properly, and we have to enforce maximum safe
+ * MRRS, which is 256 bytes.
+ */
+#ifdef CONFIG_MIPS
+static void loongson_set_min_mrrs_quirk(struct pci_dev *pdev)
+{
+ struct pci_bus *bus = pdev->bus;
+ struct pci_dev *bridge;
+ static const struct pci_device_id bridge_devids[] = {
+ { PCI_VDEVICE(LOONGSON, DEV_LS2K_PCIE_PORT0) },
+ { PCI_VDEVICE(LOONGSON, DEV_LS7A_PCIE_PORT0) },
+ { PCI_VDEVICE(LOONGSON, DEV_LS7A_PCIE_PORT1) },
+ { PCI_VDEVICE(LOONGSON, DEV_LS7A_PCIE_PORT2) },
+ { PCI_VDEVICE(LOONGSON, DEV_LS7A_PCIE_PORT3) },
+ { PCI_VDEVICE(LOONGSON, DEV_LS7A_PCIE_PORT4) },
+ { PCI_VDEVICE(LOONGSON, DEV_LS7A_PCIE_PORT5) },
+ { PCI_VDEVICE(LOONGSON, DEV_LS7A_PCIE_PORT6) },
+ { 0, },
+ };
+
+ /* look for the matching bridge */
+ while (!pci_is_root_bus(bus)) {
+ bridge = bus->self;
+ bus = bus->parent;
+
+ if (pci_match_id(bridge_devids, bridge)) {
+ if (pcie_get_readrq(pdev) > 256) {
+ pci_info(pdev, "limiting MRRS to 256\n");
+ pcie_set_readrq(pdev, 256);
+ }
+ break;
+ }
+ }
+}
+DECLARE_PCI_FIXUP_ENABLE(PCI_ANY_ID, PCI_ANY_ID, loongson_mrrs_quirk_old);
+#endif
+
static void loongson_mrrs_quirk(struct pci_dev *pdev)
{
- /*
- * Some Loongson PCIe ports have h/w limitations of maximum read
- * request size. They can't handle anything larger than this. So
- * force this limit on any devices attached under these ports.
- */
struct pci_host_bridge *bridge = pci_find_host_bridge(pdev->bus);
bridge->no_inc_mrrs = 1;
--
2.34.1
From: Mingzhe Zou <mingzhe.zou(a)easystack.cn>
We get a kernel crash about "unable to handle kernel paging request":
```dmesg
[368033.032005] BUG: unable to handle kernel paging request at ffffffffad9ae4b5
[368033.032007] PGD fc3a0d067 P4D fc3a0d067 PUD fc3a0e063 PMD 8000000fc38000e1
[368033.032012] Oops: 0003 [#1] SMP PTI
[368033.032015] CPU: 23 PID: 55090 Comm: bch_dirtcnt[0] Kdump: loaded Tainted: G OE --------- - - 4.18.0-147.5.1.es8_24.x86_64 #1
[368033.032017] Hardware name: Tsinghua Tongfang THTF Chaoqiang Server/072T6D, BIOS 2.4.3 01/17/2017
[368033.032027] RIP: 0010:native_queued_spin_lock_slowpath+0x183/0x1d0
[368033.032029] Code: 8b 02 48 85 c0 74 f6 48 89 c1 eb d0 c1 e9 12 83 e0
03 83 e9 01 48 c1 e0 05 48 63 c9 48 05 c0 3d 02 00 48 03 04 cd 60 68 93
ad <48> 89 10 8b 42 08 85 c0 75 09 f3 90 8b 42 08 85 c0 74 f7 48 8b 02
[368033.032031] RSP: 0018:ffffbb48852abe00 EFLAGS: 00010082
[368033.032032] RAX: ffffffffad9ae4b5 RBX: 0000000000000246 RCX: 0000000000003bf3
[368033.032033] RDX: ffff97b0ff8e3dc0 RSI: 0000000000600000 RDI: ffffbb4884743c68
[368033.032034] RBP: 0000000000000001 R08: 0000000000000000 R09: 000007ffffffffff
[368033.032035] R10: ffffbb486bb01000 R11: 0000000000000001 R12: ffffffffc068da70
[368033.032036] R13: 0000000000000003 R14: 0000000000000000 R15: 0000000000000000
[368033.032038] FS: 0000000000000000(0000) GS:ffff97b0ff8c0000(0000) knlGS:0000000000000000
[368033.032039] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[368033.032040] CR2: ffffffffad9ae4b5 CR3: 0000000fc3a0a002 CR4: 00000000003626e0
[368033.032042] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[368033.032043] bcache: bch_cached_dev_attach() Caching rbd479 as bcache462 on set 8cff3c36-4a76-4242-afaa-7630206bc70b
[368033.032045] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[368033.032046] Call Trace:
[368033.032054] _raw_spin_lock_irqsave+0x32/0x40
[368033.032061] __wake_up_common_lock+0x63/0xc0
[368033.032073] ? bch_ptr_invalid+0x10/0x10 [bcache]
[368033.033502] bch_dirty_init_thread+0x14c/0x160 [bcache]
[368033.033511] ? read_dirty_submit+0x60/0x60 [bcache]
[368033.033516] kthread+0x112/0x130
[368033.033520] ? kthread_flush_work_fn+0x10/0x10
[368033.034505] ret_from_fork+0x35/0x40
```
The crash occurred when call wake_up(&state->wait), and then we want
to look at the value in the state. However, bch_sectors_dirty_init()
is not found in the stack of any task. Since state is allocated on
the stack, we guess that bch_sectors_dirty_init() has exited, causing
bch_dirty_init_thread() to be unable to handle kernel paging request.
In order to verify this idea, we added some printing information during
wake_up(&state->wait). We find that "wake up" is printed twice, however
we only expect the last thread to wake up once.
```dmesg
[ 994.641004] alcache: bch_dirty_init_thread() wake up
[ 994.641018] alcache: bch_dirty_init_thread() wake up
[ 994.641523] alcache: bch_sectors_dirty_init() init exit
```
There is a race. If bch_sectors_dirty_init() exits after the first wake
up, the second wake up will trigger this bug("unable to handle kernel
paging request").
Proceed as follows:
bch_sectors_dirty_init
kthread_run ==============> bch_dirty_init_thread(bch_dirtcnt[0])
... ...
atomic_inc(&state.started) ...
... ...
atomic_read(&state.enough) ...
... atomic_set(&state->enough, 1)
kthread_run ======================================================> bch_dirty_init_thread(bch_dirtcnt[1])
... atomic_dec_and_test(&state->started) ...
atomic_inc(&state.started) ... ...
... wake_up(&state->wait) ...
atomic_read(&state.enough) atomic_dec_and_test(&state->started)
... ...
wait_event(state.wait, atomic_read(&state.started) == 0) ...
return ...
wake_up(&state->wait)
We believe it is very common to wake up twice if there is no dirty, but
crash is an extremely low probability event. It's hard for us to reproduce
this issue. We attached and detached continuously for a week, with a total
of more than one million attaches and only one crash.
Putting atomic_inc(&state.started) before kthread_run() can avoid waking
up twice.
Fixes: b144e45fc576 ("bcache: make bch_sectors_dirty_init() to be multithreaded")
Signed-off-by: Mingzhe Zou <mingzhe.zou(a)easystack.cn>
Cc: stable(a)vger.kernel.org
Signed-off-by: Coly Li <colyli(a)suse.de>
---
drivers/md/bcache/writeback.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/md/bcache/writeback.c b/drivers/md/bcache/writeback.c
index a1d760916246..3accfdaee6b1 100644
--- a/drivers/md/bcache/writeback.c
+++ b/drivers/md/bcache/writeback.c
@@ -1025,17 +1025,18 @@ void bch_sectors_dirty_init(struct bcache_device *d)
if (atomic_read(&state.enough))
break;
+ atomic_inc(&state.started);
state.infos[i].state = &state;
state.infos[i].thread =
kthread_run(bch_dirty_init_thread, &state.infos[i],
"bch_dirtcnt[%d]", i);
if (IS_ERR(state.infos[i].thread)) {
pr_err("fails to run thread bch_dirty_init[%d]\n", i);
+ atomic_dec(&state.started);
for (--i; i >= 0; i--)
kthread_stop(state.infos[i].thread);
goto out;
}
- atomic_inc(&state.started);
}
out:
--
2.35.3
From: Mingzhe Zou <mingzhe.zou(a)easystack.cn>
We found that after long run, the dirty_data of the bcache device
will have errors. This error cannot be eliminated unless re-register.
We also found that reattach after detach, this error can accumulate.
In bch_sectors_dirty_init(), all inode <= d->id keys will be recounted
again. This is wrong, we only need to count the keys of the current
device.
Fixes: b144e45fc576 ("bcache: make bch_sectors_dirty_init() to be multithreaded")
Signed-off-by: Mingzhe Zou <mingzhe.zou(a)easystack.cn>
Cc: stable(a)vger.kernel.org
Signed-off-by: Coly Li <colyli(a)suse.de>
---
drivers/md/bcache/writeback.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/md/bcache/writeback.c b/drivers/md/bcache/writeback.c
index c3e872e0a6f2..77fb72ac6b81 100644
--- a/drivers/md/bcache/writeback.c
+++ b/drivers/md/bcache/writeback.c
@@ -991,8 +991,11 @@ void bch_sectors_dirty_init(struct bcache_device *d)
op.count = 0;
for_each_key_filter(&c->root->keys,
- k, &iter, bch_ptr_invalid)
+ k, &iter, bch_ptr_invalid) {
+ if (KEY_INODE(k) != op.inode)
+ continue;
sectors_dirty_init_fn(&op.op, c->root, k);
+ }
rw_unlock(0, c->root);
return;
--
2.35.3
From: Rand Deeb <rand.sec96(a)gmail.com>
In SHOW(), the variable 'n' is of type 'size_t.' While there is a
conditional check to verify that 'n' is not equal to zero before
executing the 'do_div' macro, concerns arise regarding potential
division by zero error in 64-bit environments.
The concern arises when 'n' is 64 bits in size, greater than zero, and
the lower 32 bits of it are zeros. In such cases, the conditional check
passes because 'n' is non-zero, but the 'do_div' macro casts 'n' to
'uint32_t,' effectively truncating it to its lower 32 bits.
Consequently, the 'n' value becomes zero.
To fix this potential division by zero error and ensure precise
division handling, this commit replaces the 'do_div' macro with
div64_u64(). div64_u64() is designed to work with 64-bit operands,
guaranteeing that division is performed correctly.
This change enhances the robustness of the code, ensuring that division
operations yield accurate results in all scenarios, eliminating the
possibility of division by zero, and improving compatibility across
different 64-bit environments.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Signed-off-by: Rand Deeb <rand.sec96(a)gmail.com>
Cc: stable(a)vger.kernel.org
Signed-off-by: Coly Li <colyli(a)suse.de>
---
drivers/md/bcache/sysfs.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/md/bcache/sysfs.c b/drivers/md/bcache/sysfs.c
index 45d8af755de6..a438efb66069 100644
--- a/drivers/md/bcache/sysfs.c
+++ b/drivers/md/bcache/sysfs.c
@@ -1104,7 +1104,7 @@ SHOW(__bch_cache)
sum += INITIAL_PRIO - cached[i];
if (n)
- do_div(sum, n);
+ sum = div64_u64(sum, n);
for (i = 0; i < ARRAY_SIZE(q); i++)
q[i] = INITIAL_PRIO - cached[n * (i + 1) /
--
2.35.3
In btree_gc_rewrite_node(), pointer 'n' is not checked after it returns
from btree_gc_rewrite_node(). There is potential possibility that 'n' is
a non NULL ERR_PTR(), referencing such error code is not permitted in
following code. Therefore a return value checking is necessary after 'n'
is back from btree_node_alloc_replacement().
Signed-off-by: Coly Li <colyli(a)suse.de>
Reported-by: Dan Carpenter <dan.carpenter(a)linaro.org>
Cc: stable(a)vger.kernel.org
---
drivers/md/bcache/btree.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/md/bcache/btree.c b/drivers/md/bcache/btree.c
index ae5cbb55861f..de8d552201dc 100644
--- a/drivers/md/bcache/btree.c
+++ b/drivers/md/bcache/btree.c
@@ -1532,6 +1532,8 @@ static int btree_gc_rewrite_node(struct btree *b, struct btree_op *op,
return 0;
n = btree_node_alloc_replacement(replace, NULL);
+ if (IS_ERR(n))
+ return 0;
/* recheck reserve after allocating replacement node */
if (btree_check_reserve(b, NULL)) {
--
2.35.3
Registers r7 is removed in clobber list, so compiler may choose r7 for
local variables usage, while r7 will be actually updated by the inline asm
code. This caused the runtime behavior wrong.
While those kind of reserved registers cannot be set to clobber list
because of error like "inline asm clobber list contains reserved
registers".
Explicitly reserve r7 by adding attribute no-omit-frame-pointer for needed
function, then in T32 asm code r7 is used as a frame pointer and is not
available for use as a general-purpose register.
Note that "no-omit-frame-pointer" will make the code size a little bigger
to store the stack frame pointer. So limited to needed functions can have
the less impact than the full source file.
Fixes: dd12e97f3c72 ("ARM: kprobes: treat R7 as the frame pointer register in Thumb2 builds")
Signed-off-by: Maria Yu <quic_aiquny(a)quicinc.com>
Cc: stable(a)vger.kernel.org
---
arch/arm/probes/kprobes/actions-thumb.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/arch/arm/probes/kprobes/actions-thumb.c b/arch/arm/probes/kprobes/actions-thumb.c
index 51624fc263fc..c2fdaf9f6dba 100644
--- a/arch/arm/probes/kprobes/actions-thumb.c
+++ b/arch/arm/probes/kprobes/actions-thumb.c
@@ -438,7 +438,7 @@ t16_simulate_branch(probes_opcode_t insn,
regs->ARM_pc = pc + (offset * 2);
}
-static unsigned long __kprobes
+static unsigned long __kprobes __attribute__((optimize("no-omit-frame-pointer")))
t16_emulate_loregs(probes_opcode_t insn,
struct arch_probes_insn *asi, struct pt_regs *regs)
{
@@ -521,7 +521,7 @@ t16_decode_hiregs(probes_opcode_t insn, struct arch_probes_insn *asi,
return INSN_GOOD;
}
-static void __kprobes
+static void __kprobes __attribute__((optimize("no-omit-frame-pointer")))
t16_emulate_push(probes_opcode_t insn,
struct arch_probes_insn *asi, struct pt_regs *regs)
{
@@ -557,7 +557,7 @@ t16_decode_push(probes_opcode_t insn, struct arch_probes_insn *asi,
return INSN_GOOD;
}
-static void __kprobes
+static void __kprobes __attribute__((optimize("no-omit-frame-pointer")))
t16_emulate_pop_nopc(probes_opcode_t insn,
struct arch_probes_insn *asi, struct pt_regs *regs)
{
@@ -576,7 +576,7 @@ t16_emulate_pop_nopc(probes_opcode_t insn,
);
}
-static void __kprobes
+static void __kprobes __attribute__((optimize("no-omit-frame-pointer")))
t16_emulate_pop_pc(probes_opcode_t insn,
struct arch_probes_insn *asi, struct pt_regs *regs)
{
base-commit: 9bacdd8996c77c42ca004440be610692275ff9d0
--
2.17.1
Hey there guys,
This is my first kernel "bug" report ever, so please bear with me if I
didn't catch the precise right way to report this.
The bug I've found:
I'm running stable kernel 6.6.1-1 and as soon as I install it, many of
my mouse's hardware buttons stop working. I have a Logitech G502 X Plus
(it's a wireless mouse). As soon as I install 6.6.1 the mouse's hardware
buttons won't work, i.e. only the two side-buttons would work, not the
buttons (and/or my created profiles/macros) would. I have a few macros
assigned to some buttons, which work perfectly fine under 6.5.11 (and
earlier), but as soon as I'm on 6.6 they'd stop working.
Just wanted to report this and I hope there can be a fix.
I hope this email was not too much out of the ordinary.
Have a great evening guys!
Best,
André