Learn Editor: Update c26133.md

Author: Rastaban

docs/code-quality/c26133.md

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-Warning C26133
+# Warning C26133
+
+> Caller failing to hold lock '*lock 1*' before calling function '*function name*', but '*lock 2*' is held instead. Possible annotation mismatch.
+
+Warning C26133is issued when the analyzer detects that the lock that is required to call a function, is not held when the function is called. However, another lock that appears to be related is held. It is possible the code is thread safe, and the annotations need to be updated.
+
+## Examples
+
+In the following example, C26133 is emitted when `DoTaskWithCustomLock` is called.
+
+>  warning C26133: Caller failing to hold lock 'customLock01' before calling function 'DoTaskWithCustomLock', but '(&customLock01)->cs' is held instead. Possible annotation mismatch.
+
+```cpp
+#include <sal.h>
+
+struct CustomLock {
+    int cs; // "Critical Section"
+};
+
+_Acquires_exclusive_lock_(criticalSection->cs) // notice the `->` indirection
+void CustomLockAcquire(CustomLock* criticalSection);
+
+_Releases_lock_(criticalSection->cs) // notice the `->` indirection
+void CustomLockRelease(CustomLock* criticalSection);
+
+CustomLock customLock01;
+
+_Requires_lock_held_(customLock01) void DoTaskWithCustomLock();
+
+void DoTask()
+{
+    CustomLockAcquire(&customLock01);
+    DoTaskWithCustomLock(); // C26133
+    CustomLockRelease(&customLock01);
+}
+```
+
+In this example the `DoTask` function is thread safe and behaves as designed, but that design is not correctly reflected in the concurrency SAL annotations. This is fixed by adjusting the annotations on the custom locking functions to use `criticalSection` rather than `criticalSection->cs`. This could also be fixed by changing the `_Requires_lock_held_` annotation from `customLock01` to `customLock01.cs`.
+
+```cpp
+#include <sal.h>
+
+struct CustomLock {
+    int cs; // "Critical Section"
+};
+
+_Acquires_exclusive_lock_(criticalSection)
+void CustomLockAcquire(CustomLock* criticalSection);
+
+_Releases_lock_(criticalSection)
+void CustomLockRelease(CustomLock* criticalSection);
+
+CustomLock customLock01;
+
+_Requires_lock_held_(customLock01) void DoTaskWithCustomLock();
+
+void DoTask()
+{
+    CustomLockAcquire(&customLock01);
+    DoTaskWithCustomLock();
+    CustomLockRelease(&customLock01);
+}
+```