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authorLinus Torvalds <torvalds@linux-foundation.org>2019-12-21 06:17:05 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2019-12-21 06:17:05 -0800
commit6d04182dd36dc5a4dd2e352c1d0f0241e83bd2a0 (patch)
treeac6410af46ba70335e84c87651ecdfb40076828d /drivers/misc
parent5c741e2583d2e5a3fc148a5e8a2464bbaa45a1d9 (diff)
parent228b607d8ea1b7d4561945058d5692709099d432 (diff)
Merge tag 'powerpc-5.5-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc fixes from Michael Ellerman: "Two weeks worth of accumulated fixes: - A fix for a performance regression seen on PowerVM LPARs using dedicated CPUs, caused by our vcpu_is_preempted() returning true even for idle CPUs. - One of the ultravisor support patches broke KVM on big endian hosts in v5.4. - Our KUAP (Kernel User Access Prevention) code missed allowing access in __clear_user(), which could lead to an oops or erroneous SEGV when triggered via PTRACE_GETREGSET. - Two fixes for the ocxl driver, an open/remove race, and a memory leak in an error path. - A handful of other small fixes. Thanks to: Andrew Donnellan, Christian Zigotzky, Christophe Leroy, Christoph Hellwig, Daniel Axtens, David Hildenbrand, Frederic Barrat, Gautham R. Shenoy, Greg Kurz, Ihor Pasichnyk, Juri Lelli, Marcus Comstedt, Mike Rapoport, Parth Shah, Srikar Dronamraju, Vaidyanathan Srinivasan" * tag 'powerpc-5.5-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: KVM: PPC: Book3S HV: Fix regression on big endian hosts powerpc: Fix __clear_user() with KUAP enabled powerpc/pseries/cmm: fix managed page counts when migrating pages between zones powerpc/8xx: fix bogus __init on mmu_mapin_ram_chunk() ocxl: Fix potential memory leak on context creation powerpc/irq: fix stack overflow verification powerpc: Ensure that swiotlb buffer is allocated from low memory powerpc/shared: Use static key to detect shared processor powerpc/vcpu: Assume dedicated processors as non-preempt ocxl: Fix concurrent AFU open and device removal
Diffstat (limited to 'drivers/misc')
-rw-r--r--drivers/misc/ocxl/context.c8
-rw-r--r--drivers/misc/ocxl/file.c23
2 files changed, 15 insertions, 16 deletions
diff --git a/drivers/misc/ocxl/context.c b/drivers/misc/ocxl/context.c
index 994563a078eb..de8a66b9d76b 100644
--- a/drivers/misc/ocxl/context.c
+++ b/drivers/misc/ocxl/context.c
@@ -10,18 +10,17 @@ int ocxl_context_alloc(struct ocxl_context **context, struct ocxl_afu *afu,
int pasid;
struct ocxl_context *ctx;
- *context = kzalloc(sizeof(struct ocxl_context), GFP_KERNEL);
- if (!*context)
+ ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
+ if (!ctx)
return -ENOMEM;
- ctx = *context;
-
ctx->afu = afu;
mutex_lock(&afu->contexts_lock);
pasid = idr_alloc(&afu->contexts_idr, ctx, afu->pasid_base,
afu->pasid_base + afu->pasid_max, GFP_KERNEL);
if (pasid < 0) {
mutex_unlock(&afu->contexts_lock);
+ kfree(ctx);
return pasid;
}
afu->pasid_count++;
@@ -43,6 +42,7 @@ int ocxl_context_alloc(struct ocxl_context **context, struct ocxl_afu *afu,
* duration of the life of the context
*/
ocxl_afu_get(afu);
+ *context = ctx;
return 0;
}
EXPORT_SYMBOL_GPL(ocxl_context_alloc);
diff --git a/drivers/misc/ocxl/file.c b/drivers/misc/ocxl/file.c
index 2870c25da166..4d1b44de1492 100644
--- a/drivers/misc/ocxl/file.c
+++ b/drivers/misc/ocxl/file.c
@@ -18,18 +18,15 @@ static struct class *ocxl_class;
static struct mutex minors_idr_lock;
static struct idr minors_idr;
-static struct ocxl_file_info *find_file_info(dev_t devno)
+static struct ocxl_file_info *find_and_get_file_info(dev_t devno)
{
struct ocxl_file_info *info;
- /*
- * We don't declare an RCU critical section here, as our AFU
- * is protected by a reference counter on the device. By the time the
- * info reference is removed from the idr, the ref count of
- * the device is already at 0, so no user API will access that AFU and
- * this function can't return it.
- */
+ mutex_lock(&minors_idr_lock);
info = idr_find(&minors_idr, MINOR(devno));
+ if (info)
+ get_device(&info->dev);
+ mutex_unlock(&minors_idr_lock);
return info;
}
@@ -58,14 +55,16 @@ static int afu_open(struct inode *inode, struct file *file)
pr_debug("%s for device %x\n", __func__, inode->i_rdev);
- info = find_file_info(inode->i_rdev);
+ info = find_and_get_file_info(inode->i_rdev);
if (!info)
return -ENODEV;
rc = ocxl_context_alloc(&ctx, info->afu, inode->i_mapping);
- if (rc)
+ if (rc) {
+ put_device(&info->dev);
return rc;
-
+ }
+ put_device(&info->dev);
file->private_data = ctx;
return 0;
}
@@ -487,7 +486,6 @@ static void info_release(struct device *dev)
{
struct ocxl_file_info *info = container_of(dev, struct ocxl_file_info, dev);
- free_minor(info);
ocxl_afu_put(info->afu);
kfree(info);
}
@@ -577,6 +575,7 @@ void ocxl_file_unregister_afu(struct ocxl_afu *afu)
ocxl_file_make_invisible(info);
ocxl_sysfs_unregister_afu(info);
+ free_minor(info);
device_unregister(&info->dev);
}