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-rw-r--r--recipes-extended/qat/files/0001-usdm_drv-convert-mutex_lock-to-mutex_trylock-to-avio.patch104
1 files changed, 104 insertions, 0 deletions
diff --git a/recipes-extended/qat/files/0001-usdm_drv-convert-mutex_lock-to-mutex_trylock-to-avio.patch b/recipes-extended/qat/files/0001-usdm_drv-convert-mutex_lock-to-mutex_trylock-to-avio.patch
new file mode 100644
index 0000000..00d984a
--- /dev/null
+++ b/recipes-extended/qat/files/0001-usdm_drv-convert-mutex_lock-to-mutex_trylock-to-avio.patch
@@ -0,0 +1,104 @@
+From 2a4c1dd6bedeb03e5a7a2d3d4ee73dbfdda0add2 Mon Sep 17 00:00:00 2001
+From: Liwei Song <liwei.song@windriver.com>
+Date: Thu, 22 Jul 2021 08:09:05 +0000
+Subject: [PATCH] usdm_drv: convert mutex_lock to mutex_trylock to aviod
+
+ deadlock
+
+exist the following deadlock when run cpa_sample_code:
+
+======================================================
+WARNING: possible circular locking dependency detected
+5.10.47-yocto-standard #1 Tainted: G O
+------------------------------------------------------
+
+cpa_sample_code/2144 is trying to acquire lock:
+ffffffffc04883d0 (&dev_mem_lock
+=============================
+){+.+.}-{3:3}, at: mem_mmap+0x32/0x160 [usdm_drv]
+
+but task is already holding lock:
+ff1ab034bf111278 (&mm->mmap_lock#2){++++}-{3:3}, at:
+vm_mmap_pgoff+0x99/0x100
+
+which lock already depends on the new lock.
+
+the existing dependency chain (in reverse order) is:
+
+-> #1 (&mm->mmap_lock#2){++++}-{3:3}:
+ __lock_acquire+0x4be/0x980
+ lock_acquire+0xe1/0x2f0
+WARNING: suspicious RCU usage
+ __might_fault+0x5e/0x80
+ _copy_to_user+0x23/0xa0
+ mem_ioctl+0x2ed/0x3b5 [usdm_drv]
+ __x64_sys_ioctl+0x91/0xc0
+ do_syscall_64+0x38/0x50
+ entry_SYSCALL_64_after_hwframe+0x44/0xa9
+5.10.47-yocto-standard #1 Tainted: G O
+
+-> #0 (&dev_mem_lock){+.+.}-{3:3}:
+ check_prev_add+0x95/0xc00
+ validate_chain+0x723/0xaa0
+ __lock_acquire+0x4be/0x980
+ lock_acquire+0xe1/0x2f0
+ __mutex_lock+0x97/0x960
+ mutex_lock_nested+0x1b/0x20
+ mem_mmap+0x32/0x160 [usdm_drv]
+-----------------------------
+ mmap_region+0x423/0x6b0
+ do_mmap+0x46a/0x5e0
+ vm_mmap_pgoff+0xc5/0x100
+ ksys_mmap_pgoff+0x1d0/0x230
+ __x64_sys_mmap+0x33/0x40
+ do_syscall_64+0x38/0x50
+ entry_SYSCALL_64_after_hwframe+0x44/0xa9
+kernel/sched/core.c:7263 Illegal context switch in RCU-bh read-side
+critical section!
+
+other info that might help us debug this:
+
+ Possible unsafe locking scenario:
+
+ CPU0 CPU1
+ ---- ----
+ lock(&mm->mmap_lock#2);
+ lock(&dev_mem_lock);
+ lock(&mm->mmap_lock#2);
+ lock(&dev_mem_lock);
+
+ *** DEADLOCK ***
+
+convert mutex_lock to mutex_trylock which will return without wait.
+
+Upstream-Status: Inappropriate
+
+Signed-off-by: Liwei Song <liwei.song@windriver.com>
+---
+ .../utilities/libusdm_drv/linux/kernel_space/qae_mem_drv.c | 6 +++++-
+ 1 file changed, 5 insertions(+), 1 deletion(-)
+
+diff --git a/quickassist/utilities/libusdm_drv/linux/kernel_space/qae_mem_drv.c b/quickassist/utilities/libusdm_drv/linux/kernel_space/qae_mem_drv.c
+index d73cb0d..06e5d15 100644
+--- a/quickassist/utilities/libusdm_drv/linux/kernel_space/qae_mem_drv.c
++++ b/quickassist/utilities/libusdm_drv/linux/kernel_space/qae_mem_drv.c
+@@ -87,6 +87,7 @@
+ #include <linux/uaccess.h>
+ #include <linux/version.h>
+ #include <linux/hugetlb.h>
++#include <linux/delay.h>
+
+ #include "qae_mem_utils.h"
+
+@@ -1049,7 +1050,10 @@ mem_mmap(struct file *fp, struct vm_area_struct *vma)
+ uint64_t pages = size >> PAGE_SHIFT;
+ id = vma->vm_pgoff << PAGE_SHIFT;
+
+- mutex_lock(&dev_mem_lock);
++ while(!mutex_trylock(&dev_mem_lock)){
++ udelay(5);
++ }
++
+ kmem = userMemGetInfo(fp, id);
+ if (!kmem)
+ {