[PATCH AUTOSEL 5.1 14/59] fpga: stratix10-soc: fix use-after-free on s10_init()

[PATCH AUTOSEL 5.1 14/59] fpga: stratix10-soc: fix use-after-free on s10_init()

[Sasha Levin]

From: Wen Yang <wen.yang99@zte.com.cn>

[ Upstream commit f5dd87326fefe42a4b1a4b1a1a695060c33a88d6 ]

The refcount of fw_np has already been decreased by of_find_matching_node()
so it shouldn't be used anymore.
This patch adds an of_node_get() before of_find_matching_node() to avoid
the use-after-free problem.

Fixes: e7eef1d7633a ("fpga: add intel stratix10 soc fpga manager driver")
Signed-off-by: Wen Yang <wen.yang99@zte.com.cn>
Cc: Alan Tull <atull@kernel.org>
Cc: Moritz Fischer <mdf@kernel.org>
Cc: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Cc: linux-fpga@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Reviewed-by: Moritz Fischer <mdf@kernel.org>
Reviewed-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Acked-by: Alan Tull <atull@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/fpga/stratix10-soc.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/fpga/stratix10-soc.c b/drivers/fpga/stratix10-soc.c
index 13851b3d1c56..215d33789c74 100644
--- a/drivers/fpga/stratix10-soc.c
+++ b/drivers/fpga/stratix10-soc.c
@@ -507,12 +507,16 @@ static int __init s10_init(void)
 	if (!fw_np)
 		return -ENODEV;
 
+	of_node_get(fw_np);
 	np = of_find_matching_node(fw_np, s10_of_match);
-	if (!np)
+	if (!np) {
+		of_node_put(fw_np);
 		return -ENODEV;
+	}
 
 	of_node_put(np);
 	ret = of_platform_populate(fw_np, s10_of_match, NULL, NULL);
+	of_node_put(fw_np);
 	if (ret)
 		return ret;
 
-- 
2.20.1

[PATCH AUTOSEL 5.1 15/59] fpga: dfl: afu: Pass the correct device to dma_mapping_error()

[Sasha Levin]

From: Scott Wood <swood@redhat.com>

[ Upstream commit 13069847a475b60069918dc9971f5adb42811ce3 ]

dma_mapping_error() was being called on a different device struct than
what was passed to map/unmap.  Besides rendering the error checking
ineffective, it caused a debug splat with CONFIG_DMA_API_DEBUG.

Signed-off-by: Scott Wood <swood@redhat.com>
Acked-by: Wu Hao <hao.wu@intel.com>
Acked-by: Moritz Fischer <mdf@kernel.org>
Acked-by: Alan Tull <atull@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/fpga/dfl-afu-dma-region.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/fpga/dfl-afu-dma-region.c b/drivers/fpga/dfl-afu-dma-region.c
index e18a786fc943..cd68002ac097 100644
--- a/drivers/fpga/dfl-afu-dma-region.c
+++ b/drivers/fpga/dfl-afu-dma-region.c
@@ -399,7 +399,7 @@ int afu_dma_map_region(struct dfl_feature_platform_data *pdata,
 				    region->pages[0], 0,
 				    region->length,
 				    DMA_BIDIRECTIONAL);
-	if (dma_mapping_error(&pdata->dev->dev, region->iova)) {
+	if (dma_mapping_error(dfl_fpga_pdata_to_parent(pdata), region->iova)) {
 		dev_err(&pdata->dev->dev, "failed to map for dma\n");
 		ret = -EFAULT;
 		goto unpin_pages;
-- 
2.20.1

[PATCH AUTOSEL 5.1 16/59] fpga: dfl: Add lockdep classes for pdata->lock

[Sasha Levin]

From: Scott Wood <swood@redhat.com>

[ Upstream commit dfe3de8d397bf878b31864d4e489d41118ec475f ]

struct dfl_feature_platform_data (and it's mutex) is used
by both fme and port devices, and when lockdep is enabled it
complains about nesting between these locks.  Tell lockdep about
the difference so it can track each class separately.

Here's the lockdep complaint:
[  409.680668] WARNING: possible recursive locking detected
[  409.685983] 5.1.0-rc3.fpga+ #1 Tainted: G            E
[  409.691469] --------------------------------------------
[  409.696779] fpgaconf/9348 is trying to acquire lock:
[  409.701746] 00000000a443fe2e (&pdata->lock){+.+.}, at: port_enable_set+0x24/0x60 [dfl_afu]
[  409.710006]
[  409.710006] but task is already holding lock:
[  409.715837] 0000000063b78782 (&pdata->lock){+.+.}, at: fme_pr_ioctl+0x21d/0x330 [dfl_fme]
[  409.724012]
[  409.724012] other info that might help us debug this:
[  409.730535]  Possible unsafe locking scenario:
[  409.730535]
[  409.736457]        CPU0
[  409.738910]        ----
[  409.741360]   lock(&pdata->lock);
[  409.744679]   lock(&pdata->lock);
[  409.747999]
[  409.747999]  *** DEADLOCK ***
[  409.747999]
[  409.753920]  May be due to missing lock nesting notation
[  409.753920]
[  409.760704] 4 locks held by fpgaconf/9348:
[  409.764805]  #0: 0000000063b78782 (&pdata->lock){+.+.}, at: fme_pr_ioctl+0x21d/0x330 [dfl_fme]
[  409.773408]  #1: 00000000213c8a66 (&region->mutex){+.+.}, at: fpga_region_program_fpga+0x24/0x200 [fpga_region]
[  409.783489]  #2: 00000000fe63afb9 (&mgr->ref_mutex){+.+.}, at: fpga_mgr_lock+0x15/0x40 [fpga_mgr]
[  409.792354]  #3: 000000000b2285c5 (&bridge->mutex){+.+.}, at: __fpga_bridge_get+0x26/0xa0 [fpga_bridge]
[  409.801740]
[  409.801740] stack backtrace:
[  409.806102] CPU: 45 PID: 9348 Comm: fpgaconf Kdump: loaded Tainted: G            E     5.1.0-rc3.fpga+ #1
[  409.815658] Hardware name: Intel Corporation S2600BT/S2600BT, BIOS SE5C620.86B.01.00.0763.022420181017 02/24/2018
[  409.825911] Call Trace:
[  409.828369]  dump_stack+0x5e/0x8b
[  409.831686]  __lock_acquire+0xf3d/0x10e0
[  409.835612]  ? find_held_lock+0x3c/0xa0
[  409.839451]  lock_acquire+0xbc/0x1d0
[  409.843030]  ? port_enable_set+0x24/0x60 [dfl_afu]
[  409.847823]  ? port_enable_set+0x24/0x60 [dfl_afu]
[  409.852616]  __mutex_lock+0x86/0x970
[  409.856195]  ? port_enable_set+0x24/0x60 [dfl_afu]
[  409.860989]  ? port_enable_set+0x24/0x60 [dfl_afu]
[  409.865777]  ? __mutex_unlock_slowpath+0x4b/0x290
[  409.870486]  port_enable_set+0x24/0x60 [dfl_afu]
[  409.875106]  fpga_bridges_disable+0x36/0x50 [fpga_bridge]
[  409.880502]  fpga_region_program_fpga+0xea/0x200 [fpga_region]
[  409.886338]  fme_pr_ioctl+0x13e/0x330 [dfl_fme]
[  409.890870]  fme_ioctl+0x66/0xe0 [dfl_fme]
[  409.894973]  do_vfs_ioctl+0xa9/0x720
[  409.898548]  ? lockdep_hardirqs_on+0xf0/0x1a0
[  409.902907]  ksys_ioctl+0x60/0x90
[  409.906225]  __x64_sys_ioctl+0x16/0x20
[  409.909981]  do_syscall_64+0x5a/0x220
[  409.913644]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
[  409.918698] RIP: 0033:0x7f9d31b9b8d7
[  409.922276] Code: 44 00 00 48 8b 05 b9 15 2d 00 64 c7 00 26 00 00 00 48 c7 c0 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 89 15 2d 00 f7 d8 64 89 01 48
[  409.941020] RSP: 002b:00007ffe4cae0d68 EFLAGS: 00000202 ORIG_RAX: 0000000000000010
[  409.948588] RAX: ffffffffffffffda RBX: 00007f9d32ade6a0 RCX: 00007f9d31b9b8d7
[  409.955719] RDX: 00007ffe4cae0df0 RSI: 000000000000b680 RDI: 0000000000000003
[  409.962852] RBP: 0000000000000003 R08: 00007f9d2b70a177 R09: 00007ffe4cae0e40
[  409.969984] R10: 00007ffe4cae0160 R11: 0000000000000202 R12: 00007ffe4cae0df0
[  409.977115] R13: 000000000000b680 R14: 0000000000000000 R15: 00007ffe4cae0f60

Signed-off-by: Scott Wood <swood@redhat.com>
Acked-by: Wu Hao <hao.wu@intel.com>
Acked-by: Alan Tull <atull@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/fpga/dfl.c | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/drivers/fpga/dfl.c b/drivers/fpga/dfl.c
index 2c09e502e721..c25217cde5ca 100644
--- a/drivers/fpga/dfl.c
+++ b/drivers/fpga/dfl.c
@@ -40,6 +40,13 @@ enum dfl_fpga_devt_type {
 	DFL_FPGA_DEVT_MAX,
 };
 
+static struct lock_class_key dfl_pdata_keys[DFL_ID_MAX];
+
+static const char *dfl_pdata_key_strings[DFL_ID_MAX] = {
+	"dfl-fme-pdata",
+	"dfl-port-pdata",
+};
+
 /**
  * dfl_dev_info - dfl feature device information.
  * @name: name string of the feature platform device.
@@ -443,11 +450,16 @@ static int build_info_commit_dev(struct build_feature_devs_info *binfo)
 	struct platform_device *fdev = binfo->feature_dev;
 	struct dfl_feature_platform_data *pdata;
 	struct dfl_feature_info *finfo, *p;
+	enum dfl_id_type type;
 	int ret, index = 0;
 
 	if (!fdev)
 		return 0;
 
+	type = feature_dev_id_type(fdev);
+	if (WARN_ON_ONCE(type >= DFL_ID_MAX))
+		return -EINVAL;
+
 	/*
 	 * we do not need to care for the memory which is associated with
 	 * the platform device. After calling platform_device_unregister(),
@@ -463,6 +475,8 @@ static int build_info_commit_dev(struct build_feature_devs_info *binfo)
 	pdata->num = binfo->feature_num;
 	pdata->dfl_cdev = binfo->cdev;
 	mutex_init(&pdata->lock);
+	lockdep_set_class_and_name(&pdata->lock, &dfl_pdata_keys[type],
+				   dfl_pdata_key_strings[type]);
 
 	/*
 	 * the count should be initialized to 0 to make sure
@@ -497,7 +511,7 @@ static int build_info_commit_dev(struct build_feature_devs_info *binfo)
 
 	ret = platform_device_add(binfo->feature_dev);
 	if (!ret) {
-		if (feature_dev_id_type(binfo->feature_dev) == PORT_ID)
+		if (type == PORT_ID)
 			dfl_fpga_cdev_add_port_dev(binfo->cdev,
 						   binfo->feature_dev);
 		else
-- 
2.20.1

[PATCH AUTOSEL 5.1 17/59] fpga: dfl: expand minor range when registering chrdev region

[Sasha Levin]

From: Chengguang Xu <cgxu519@gmx.com>

[ Upstream commit de9a7f6f5f1967d275311cca9163b4a3ffe9b0ae ]

Actually, total amount of available minor number
for a single major is MINORMASK + 1. So expand
minor range when registering chrdev region.

Signed-off-by: Chengguang Xu <cgxu519@gmx.com>
Acked-by: Wu Hao <hao.wu@intel.com>
Acked-by: Alan Tull <atull@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/fpga/dfl.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/fpga/dfl.c b/drivers/fpga/dfl.c
index c25217cde5ca..4b66aaa32b5a 100644
--- a/drivers/fpga/dfl.c
+++ b/drivers/fpga/dfl.c
@@ -322,7 +322,7 @@ static void dfl_chardev_uinit(void)
 	for (i = 0; i < DFL_FPGA_DEVT_MAX; i++)
 		if (MAJOR(dfl_chrdevs[i].devt)) {
 			unregister_chrdev_region(dfl_chrdevs[i].devt,
-						 MINORMASK);
+						 MINORMASK + 1);
 			dfl_chrdevs[i].devt = MKDEV(0, 0);
 		}
 }
@@ -332,8 +332,8 @@ static int dfl_chardev_init(void)
 	int i, ret;
 
 	for (i = 0; i < DFL_FPGA_DEVT_MAX; i++) {
-		ret = alloc_chrdev_region(&dfl_chrdevs[i].devt, 0, MINORMASK,
-					  dfl_chrdevs[i].name);
+		ret = alloc_chrdev_region(&dfl_chrdevs[i].devt, 0,
+					  MINORMASK + 1, dfl_chrdevs[i].name);
 		if (ret)
 			goto exit;
 	}
-- 
2.20.1

Re: [PATCH AUTOSEL 5.1 16/59] fpga: dfl: Add lockdep classes for pdata->lock

[Greg Kroah-Hartman]

On Fri, Jun 14, 2019 at 04:28:00PM -0400, Sasha Levin wrote:
> From: Scott Wood <swood@redhat.com>
> 
> [ Upstream commit dfe3de8d397bf878b31864d4e489d41118ec475f ]
> 
> struct dfl_feature_platform_data (and it's mutex) is used
> by both fme and port devices, and when lockdep is enabled it
> complains about nesting between these locks.  Tell lockdep about
> the difference so it can track each class separately.
> 
> Here's the lockdep complaint:
> [  409.680668] WARNING: possible recursive locking detected
> [  409.685983] 5.1.0-rc3.fpga+ #1 Tainted: G            E
> [  409.691469] --------------------------------------------
> [  409.696779] fpgaconf/9348 is trying to acquire lock:
> [  409.701746] 00000000a443fe2e (&pdata->lock){+.+.}, at: port_enable_set+0x24/0x60 [dfl_afu]
> [  409.710006]
> [  409.710006] but task is already holding lock:
> [  409.715837] 0000000063b78782 (&pdata->lock){+.+.}, at: fme_pr_ioctl+0x21d/0x330 [dfl_fme]
> [  409.724012]
> [  409.724012] other info that might help us debug this:
> [  409.730535]  Possible unsafe locking scenario:
> [  409.730535]
> [  409.736457]        CPU0
> [  409.738910]        ----
> [  409.741360]   lock(&pdata->lock);
> [  409.744679]   lock(&pdata->lock);
> [  409.747999]
> [  409.747999]  *** DEADLOCK ***
> [  409.747999]
> [  409.753920]  May be due to missing lock nesting notation
> [  409.753920]
> [  409.760704] 4 locks held by fpgaconf/9348:
> [  409.764805]  #0: 0000000063b78782 (&pdata->lock){+.+.}, at: fme_pr_ioctl+0x21d/0x330 [dfl_fme]
> [  409.773408]  #1: 00000000213c8a66 (&region->mutex){+.+.}, at: fpga_region_program_fpga+0x24/0x200 [fpga_region]
> [  409.783489]  #2: 00000000fe63afb9 (&mgr->ref_mutex){+.+.}, at: fpga_mgr_lock+0x15/0x40 [fpga_mgr]
> [  409.792354]  #3: 000000000b2285c5 (&bridge->mutex){+.+.}, at: __fpga_bridge_get+0x26/0xa0 [fpga_bridge]
> [  409.801740]
> [  409.801740] stack backtrace:
> [  409.806102] CPU: 45 PID: 9348 Comm: fpgaconf Kdump: loaded Tainted: G            E     5.1.0-rc3.fpga+ #1
> [  409.815658] Hardware name: Intel Corporation S2600BT/S2600BT, BIOS SE5C620.86B.01.00.0763.022420181017 02/24/2018
> [  409.825911] Call Trace:
> [  409.828369]  dump_stack+0x5e/0x8b
> [  409.831686]  __lock_acquire+0xf3d/0x10e0
> [  409.835612]  ? find_held_lock+0x3c/0xa0
> [  409.839451]  lock_acquire+0xbc/0x1d0
> [  409.843030]  ? port_enable_set+0x24/0x60 [dfl_afu]
> [  409.847823]  ? port_enable_set+0x24/0x60 [dfl_afu]
> [  409.852616]  __mutex_lock+0x86/0x970
> [  409.856195]  ? port_enable_set+0x24/0x60 [dfl_afu]
> [  409.860989]  ? port_enable_set+0x24/0x60 [dfl_afu]
> [  409.865777]  ? __mutex_unlock_slowpath+0x4b/0x290
> [  409.870486]  port_enable_set+0x24/0x60 [dfl_afu]
> [  409.875106]  fpga_bridges_disable+0x36/0x50 [fpga_bridge]
> [  409.880502]  fpga_region_program_fpga+0xea/0x200 [fpga_region]
> [  409.886338]  fme_pr_ioctl+0x13e/0x330 [dfl_fme]
> [  409.890870]  fme_ioctl+0x66/0xe0 [dfl_fme]
> [  409.894973]  do_vfs_ioctl+0xa9/0x720
> [  409.898548]  ? lockdep_hardirqs_on+0xf0/0x1a0
> [  409.902907]  ksys_ioctl+0x60/0x90
> [  409.906225]  __x64_sys_ioctl+0x16/0x20
> [  409.909981]  do_syscall_64+0x5a/0x220
> [  409.913644]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
> [  409.918698] RIP: 0033:0x7f9d31b9b8d7
> [  409.922276] Code: 44 00 00 48 8b 05 b9 15 2d 00 64 c7 00 26 00 00 00 48 c7 c0 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 89 15 2d 00 f7 d8 64 89 01 48
> [  409.941020] RSP: 002b:00007ffe4cae0d68 EFLAGS: 00000202 ORIG_RAX: 0000000000000010
> [  409.948588] RAX: ffffffffffffffda RBX: 00007f9d32ade6a0 RCX: 00007f9d31b9b8d7
> [  409.955719] RDX: 00007ffe4cae0df0 RSI: 000000000000b680 RDI: 0000000000000003
> [  409.962852] RBP: 0000000000000003 R08: 00007f9d2b70a177 R09: 00007ffe4cae0e40
> [  409.969984] R10: 00007ffe4cae0160 R11: 0000000000000202 R12: 00007ffe4cae0df0
> [  409.977115] R13: 000000000000b680 R14: 0000000000000000 R15: 00007ffe4cae0f60
> 
> Signed-off-by: Scott Wood <swood@redhat.com>
> Acked-by: Wu Hao <hao.wu@intel.com>
> Acked-by: Alan Tull <atull@kernel.org>
> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Signed-off-by: Sasha Levin <sashal@kernel.org>
> ---
>  drivers/fpga/dfl.c | 16 +++++++++++++++-
>  1 file changed, 15 insertions(+), 1 deletion(-)

Adding lockdep stuff is not really needed for stable kernels, please
drop this from all trees.

thanks,

greg k-h

Re: [PATCH AUTOSEL 5.1 17/59] fpga: dfl: expand minor range when registering chrdev region

[Greg Kroah-Hartman]

On Fri, Jun 14, 2019 at 04:28:01PM -0400, Sasha Levin wrote:
> From: Chengguang Xu <cgxu519@gmx.com>
> 
> [ Upstream commit de9a7f6f5f1967d275311cca9163b4a3ffe9b0ae ]
> 
> Actually, total amount of available minor number
> for a single major is MINORMASK + 1. So expand
> minor range when registering chrdev region.
> 
> Signed-off-by: Chengguang Xu <cgxu519@gmx.com>
> Acked-by: Wu Hao <hao.wu@intel.com>
> Acked-by: Alan Tull <atull@kernel.org>
> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Signed-off-by: Sasha Levin <sashal@kernel.org>
> ---
>  drivers/fpga/dfl.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/fpga/dfl.c b/drivers/fpga/dfl.c
> index c25217cde5ca..4b66aaa32b5a 100644
> --- a/drivers/fpga/dfl.c
> +++ b/drivers/fpga/dfl.c
> @@ -322,7 +322,7 @@ static void dfl_chardev_uinit(void)
>  	for (i = 0; i < DFL_FPGA_DEVT_MAX; i++)
>  		if (MAJOR(dfl_chrdevs[i].devt)) {
>  			unregister_chrdev_region(dfl_chrdevs[i].devt,
> -						 MINORMASK);
> +						 MINORMASK + 1);
>  			dfl_chrdevs[i].devt = MKDEV(0, 0);
>  		}
>  }
> @@ -332,8 +332,8 @@ static int dfl_chardev_init(void)
>  	int i, ret;
>  
>  	for (i = 0; i < DFL_FPGA_DEVT_MAX; i++) {
> -		ret = alloc_chrdev_region(&dfl_chrdevs[i].devt, 0, MINORMASK,
> -					  dfl_chrdevs[i].name);
> +		ret = alloc_chrdev_region(&dfl_chrdevs[i].devt, 0,
> +					  MINORMASK + 1, dfl_chrdevs[i].name);
>  		if (ret)
>  			goto exit;
>  	}

Not a bugfix, so not needed for stable kernels, thanks.

greg k-h

Re: [PATCH AUTOSEL 5.1 16/59] fpga: dfl: Add lockdep classes for pdata->lock

[Sasha Levin]

On Sat, Jun 15, 2019 at 07:47:39AM +0200, Greg Kroah-Hartman wrote:
>On Fri, Jun 14, 2019 at 04:28:00PM -0400, Sasha Levin wrote:
>> From: Scott Wood <swood@redhat.com>
>>
>> [ Upstream commit dfe3de8d397bf878b31864d4e489d41118ec475f ]
>>
>> struct dfl_feature_platform_data (and it's mutex) is used
>> by both fme and port devices, and when lockdep is enabled it
>> complains about nesting between these locks.  Tell lockdep about
>> the difference so it can track each class separately.
>>
>> Here's the lockdep complaint:
>> [  409.680668] WARNING: possible recursive locking detected
>> [  409.685983] 5.1.0-rc3.fpga+ #1 Tainted: G            E
>> [  409.691469] --------------------------------------------
>> [  409.696779] fpgaconf/9348 is trying to acquire lock:
>> [  409.701746] 00000000a443fe2e (&pdata->lock){+.+.}, at: port_enable_set+0x24/0x60 [dfl_afu]
>> [  409.710006]
>> [  409.710006] but task is already holding lock:
>> [  409.715837] 0000000063b78782 (&pdata->lock){+.+.}, at: fme_pr_ioctl+0x21d/0x330 [dfl_fme]
>> [  409.724012]
>> [  409.724012] other info that might help us debug this:
>> [  409.730535]  Possible unsafe locking scenario:
>> [  409.730535]
>> [  409.736457]        CPU0
>> [  409.738910]        ----
>> [  409.741360]   lock(&pdata->lock);
>> [  409.744679]   lock(&pdata->lock);
>> [  409.747999]
>> [  409.747999]  *** DEADLOCK ***
>> [  409.747999]
>> [  409.753920]  May be due to missing lock nesting notation
>> [  409.753920]
>> [  409.760704] 4 locks held by fpgaconf/9348:
>> [  409.764805]  #0: 0000000063b78782 (&pdata->lock){+.+.}, at: fme_pr_ioctl+0x21d/0x330 [dfl_fme]
>> [  409.773408]  #1: 00000000213c8a66 (&region->mutex){+.+.}, at: fpga_region_program_fpga+0x24/0x200 [fpga_region]
>> [  409.783489]  #2: 00000000fe63afb9 (&mgr->ref_mutex){+.+.}, at: fpga_mgr_lock+0x15/0x40 [fpga_mgr]
>> [  409.792354]  #3: 000000000b2285c5 (&bridge->mutex){+.+.}, at: __fpga_bridge_get+0x26/0xa0 [fpga_bridge]
>> [  409.801740]
>> [  409.801740] stack backtrace:
>> [  409.806102] CPU: 45 PID: 9348 Comm: fpgaconf Kdump: loaded Tainted: G            E     5.1.0-rc3.fpga+ #1
>> [  409.815658] Hardware name: Intel Corporation S2600BT/S2600BT, BIOS SE5C620.86B.01.00.0763.022420181017 02/24/2018
>> [  409.825911] Call Trace:
>> [  409.828369]  dump_stack+0x5e/0x8b
>> [  409.831686]  __lock_acquire+0xf3d/0x10e0
>> [  409.835612]  ? find_held_lock+0x3c/0xa0
>> [  409.839451]  lock_acquire+0xbc/0x1d0
>> [  409.843030]  ? port_enable_set+0x24/0x60 [dfl_afu]
>> [  409.847823]  ? port_enable_set+0x24/0x60 [dfl_afu]
>> [  409.852616]  __mutex_lock+0x86/0x970
>> [  409.856195]  ? port_enable_set+0x24/0x60 [dfl_afu]
>> [  409.860989]  ? port_enable_set+0x24/0x60 [dfl_afu]
>> [  409.865777]  ? __mutex_unlock_slowpath+0x4b/0x290
>> [  409.870486]  port_enable_set+0x24/0x60 [dfl_afu]
>> [  409.875106]  fpga_bridges_disable+0x36/0x50 [fpga_bridge]
>> [  409.880502]  fpga_region_program_fpga+0xea/0x200 [fpga_region]
>> [  409.886338]  fme_pr_ioctl+0x13e/0x330 [dfl_fme]
>> [  409.890870]  fme_ioctl+0x66/0xe0 [dfl_fme]
>> [  409.894973]  do_vfs_ioctl+0xa9/0x720
>> [  409.898548]  ? lockdep_hardirqs_on+0xf0/0x1a0
>> [  409.902907]  ksys_ioctl+0x60/0x90
>> [  409.906225]  __x64_sys_ioctl+0x16/0x20
>> [  409.909981]  do_syscall_64+0x5a/0x220
>> [  409.913644]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
>> [  409.918698] RIP: 0033:0x7f9d31b9b8d7
>> [  409.922276] Code: 44 00 00 48 8b 05 b9 15 2d 00 64 c7 00 26 00 00 00 48 c7 c0 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 89 15 2d 00 f7 d8 64 89 01 48
>> [  409.941020] RSP: 002b:00007ffe4cae0d68 EFLAGS: 00000202 ORIG_RAX: 0000000000000010
>> [  409.948588] RAX: ffffffffffffffda RBX: 00007f9d32ade6a0 RCX: 00007f9d31b9b8d7
>> [  409.955719] RDX: 00007ffe4cae0df0 RSI: 000000000000b680 RDI: 0000000000000003
>> [  409.962852] RBP: 0000000000000003 R08: 00007f9d2b70a177 R09: 00007ffe4cae0e40
>> [  409.969984] R10: 00007ffe4cae0160 R11: 0000000000000202 R12: 00007ffe4cae0df0
>> [  409.977115] R13: 000000000000b680 R14: 0000000000000000 R15: 00007ffe4cae0f60
>>
>> Signed-off-by: Scott Wood <swood@redhat.com>
>> Acked-by: Wu Hao <hao.wu@intel.com>
>> Acked-by: Alan Tull <atull@kernel.org>
>> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
>> Signed-off-by: Sasha Levin <sashal@kernel.org>
>> ---
>>  drivers/fpga/dfl.c | 16 +++++++++++++++-
>>  1 file changed, 15 insertions(+), 1 deletion(-)
>
>Adding lockdep stuff is not really needed for stable kernels, please
>drop this from all trees.

For actual splats? Why? I treat them as compiler warnings. Keeping these
around will just make them show up over and over in testing (at least
until we unify our testing story...).

--
Thanks,
Sasha

Re: [PATCH AUTOSEL 5.1 16/59] fpga: dfl: Add lockdep classes for pdata->lock

[Greg Kroah-Hartman]

On Sat, Jun 15, 2019 at 06:41:59PM -0400, Sasha Levin wrote:
> On Sat, Jun 15, 2019 at 07:47:39AM +0200, Greg Kroah-Hartman wrote:
> > On Fri, Jun 14, 2019 at 04:28:00PM -0400, Sasha Levin wrote:
> > > From: Scott Wood <swood@redhat.com>
> > > 
> > > [ Upstream commit dfe3de8d397bf878b31864d4e489d41118ec475f ]
> > > 
> > > struct dfl_feature_platform_data (and it's mutex) is used
> > > by both fme and port devices, and when lockdep is enabled it
> > > complains about nesting between these locks.  Tell lockdep about
> > > the difference so it can track each class separately.
> > > 
> > > Here's the lockdep complaint:
> > > [  409.680668] WARNING: possible recursive locking detected
> > > [  409.685983] 5.1.0-rc3.fpga+ #1 Tainted: G            E
> > > [  409.691469] --------------------------------------------
> > > [  409.696779] fpgaconf/9348 is trying to acquire lock:
> > > [  409.701746] 00000000a443fe2e (&pdata->lock){+.+.}, at: port_enable_set+0x24/0x60 [dfl_afu]
> > > [  409.710006]
> > > [  409.710006] but task is already holding lock:
> > > [  409.715837] 0000000063b78782 (&pdata->lock){+.+.}, at: fme_pr_ioctl+0x21d/0x330 [dfl_fme]
> > > [  409.724012]
> > > [  409.724012] other info that might help us debug this:
> > > [  409.730535]  Possible unsafe locking scenario:
> > > [  409.730535]
> > > [  409.736457]        CPU0
> > > [  409.738910]        ----
> > > [  409.741360]   lock(&pdata->lock);
> > > [  409.744679]   lock(&pdata->lock);
> > > [  409.747999]
> > > [  409.747999]  *** DEADLOCK ***
> > > [  409.747999]
> > > [  409.753920]  May be due to missing lock nesting notation
> > > [  409.753920]
> > > [  409.760704] 4 locks held by fpgaconf/9348:
> > > [  409.764805]  #0: 0000000063b78782 (&pdata->lock){+.+.}, at: fme_pr_ioctl+0x21d/0x330 [dfl_fme]
> > > [  409.773408]  #1: 00000000213c8a66 (&region->mutex){+.+.}, at: fpga_region_program_fpga+0x24/0x200 [fpga_region]
> > > [  409.783489]  #2: 00000000fe63afb9 (&mgr->ref_mutex){+.+.}, at: fpga_mgr_lock+0x15/0x40 [fpga_mgr]
> > > [  409.792354]  #3: 000000000b2285c5 (&bridge->mutex){+.+.}, at: __fpga_bridge_get+0x26/0xa0 [fpga_bridge]
> > > [  409.801740]
> > > [  409.801740] stack backtrace:
> > > [  409.806102] CPU: 45 PID: 9348 Comm: fpgaconf Kdump: loaded Tainted: G            E     5.1.0-rc3.fpga+ #1
> > > [  409.815658] Hardware name: Intel Corporation S2600BT/S2600BT, BIOS SE5C620.86B.01.00.0763.022420181017 02/24/2018
> > > [  409.825911] Call Trace:
> > > [  409.828369]  dump_stack+0x5e/0x8b
> > > [  409.831686]  __lock_acquire+0xf3d/0x10e0
> > > [  409.835612]  ? find_held_lock+0x3c/0xa0
> > > [  409.839451]  lock_acquire+0xbc/0x1d0
> > > [  409.843030]  ? port_enable_set+0x24/0x60 [dfl_afu]
> > > [  409.847823]  ? port_enable_set+0x24/0x60 [dfl_afu]
> > > [  409.852616]  __mutex_lock+0x86/0x970
> > > [  409.856195]  ? port_enable_set+0x24/0x60 [dfl_afu]
> > > [  409.860989]  ? port_enable_set+0x24/0x60 [dfl_afu]
> > > [  409.865777]  ? __mutex_unlock_slowpath+0x4b/0x290
> > > [  409.870486]  port_enable_set+0x24/0x60 [dfl_afu]
> > > [  409.875106]  fpga_bridges_disable+0x36/0x50 [fpga_bridge]
> > > [  409.880502]  fpga_region_program_fpga+0xea/0x200 [fpga_region]
> > > [  409.886338]  fme_pr_ioctl+0x13e/0x330 [dfl_fme]
> > > [  409.890870]  fme_ioctl+0x66/0xe0 [dfl_fme]
> > > [  409.894973]  do_vfs_ioctl+0xa9/0x720
> > > [  409.898548]  ? lockdep_hardirqs_on+0xf0/0x1a0
> > > [  409.902907]  ksys_ioctl+0x60/0x90
> > > [  409.906225]  __x64_sys_ioctl+0x16/0x20
> > > [  409.909981]  do_syscall_64+0x5a/0x220
> > > [  409.913644]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
> > > [  409.918698] RIP: 0033:0x7f9d31b9b8d7
> > > [  409.922276] Code: 44 00 00 48 8b 05 b9 15 2d 00 64 c7 00 26 00 00 00 48 c7 c0 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 89 15 2d 00 f7 d8 64 89 01 48
> > > [  409.941020] RSP: 002b:00007ffe4cae0d68 EFLAGS: 00000202 ORIG_RAX: 0000000000000010
> > > [  409.948588] RAX: ffffffffffffffda RBX: 00007f9d32ade6a0 RCX: 00007f9d31b9b8d7
> > > [  409.955719] RDX: 00007ffe4cae0df0 RSI: 000000000000b680 RDI: 0000000000000003
> > > [  409.962852] RBP: 0000000000000003 R08: 00007f9d2b70a177 R09: 00007ffe4cae0e40
> > > [  409.969984] R10: 00007ffe4cae0160 R11: 0000000000000202 R12: 00007ffe4cae0df0
> > > [  409.977115] R13: 000000000000b680 R14: 0000000000000000 R15: 00007ffe4cae0f60
> > > 
> > > Signed-off-by: Scott Wood <swood@redhat.com>
> > > Acked-by: Wu Hao <hao.wu@intel.com>
> > > Acked-by: Alan Tull <atull@kernel.org>
> > > Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> > > Signed-off-by: Sasha Levin <sashal@kernel.org>
> > > ---
> > >  drivers/fpga/dfl.c | 16 +++++++++++++++-
> > >  1 file changed, 15 insertions(+), 1 deletion(-)
> > 
> > Adding lockdep stuff is not really needed for stable kernels, please
> > drop this from all trees.
> 
> For actual splats? Why? I treat them as compiler warnings. Keeping these
> around will just make them show up over and over in testing (at least
> until we unify our testing story...).

Ah, good point, ok, leave this in :)

thanks,

greg k-h

Re: [PATCH AUTOSEL 5.1 17/59] fpga: dfl: expand minor range when registering chrdev region

[Sasha Levin]

On Sat, Jun 15, 2019 at 07:48:06AM +0200, Greg Kroah-Hartman wrote:
>On Fri, Jun 14, 2019 at 04:28:01PM -0400, Sasha Levin wrote:
>> From: Chengguang Xu <cgxu519@gmx.com>
>>
>> [ Upstream commit de9a7f6f5f1967d275311cca9163b4a3ffe9b0ae ]
>>
>> Actually, total amount of available minor number
>> for a single major is MINORMASK + 1. So expand
>> minor range when registering chrdev region.
>>
>> Signed-off-by: Chengguang Xu <cgxu519@gmx.com>
>> Acked-by: Wu Hao <hao.wu@intel.com>
>> Acked-by: Alan Tull <atull@kernel.org>
>> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
>> Signed-off-by: Sasha Levin <sashal@kernel.org>
>> ---
>>  drivers/fpga/dfl.c | 6 +++---
>>  1 file changed, 3 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/fpga/dfl.c b/drivers/fpga/dfl.c
>> index c25217cde5ca..4b66aaa32b5a 100644
>> --- a/drivers/fpga/dfl.c
>> +++ b/drivers/fpga/dfl.c
>> @@ -322,7 +322,7 @@ static void dfl_chardev_uinit(void)
>>  	for (i = 0; i < DFL_FPGA_DEVT_MAX; i++)
>>  		if (MAJOR(dfl_chrdevs[i].devt)) {
>>  			unregister_chrdev_region(dfl_chrdevs[i].devt,
>> -						 MINORMASK);
>> +						 MINORMASK + 1);
>>  			dfl_chrdevs[i].devt = MKDEV(0, 0);
>>  		}
>>  }
>> @@ -332,8 +332,8 @@ static int dfl_chardev_init(void)
>>  	int i, ret;
>>
>>  	for (i = 0; i < DFL_FPGA_DEVT_MAX; i++) {
>> -		ret = alloc_chrdev_region(&dfl_chrdevs[i].devt, 0, MINORMASK,
>> -					  dfl_chrdevs[i].name);
>> +		ret = alloc_chrdev_region(&dfl_chrdevs[i].devt, 0,
>> +					  MINORMASK + 1, dfl_chrdevs[i].name);
>>  		if (ret)
>>  			goto exit;
>>  	}
>
>Not a bugfix, so not needed for stable kernels, thanks.

Dropped, thanks!

--
Thanks,
Sasha