README VERSION : 1.1 README CREATION DATE : 2015-04-06 PATCH-ID : VRTSllt-6.2.1.000 PATCH NAME : VRTSllt 6.2.1.000 BASE PACKAGE NAME : VRTSllt BASE PACKAGE VERSION : 6.2.0.000 SUPERSEDED PATCHES : NONE REQUIRED PATCHES : NONE INCOMPATIBLE PATCHES : NONE SUPPORTED PADV : rhel6_x86_64 (P-PLATFORM , A-ARCHITECTURE , D-DISTRIBUTION , V-VERSION) PATCH CATEGORY : CORE , PANIC PATCH CRITICALITY : CRITICAL HAS KERNEL COMPONENT : YES ID : NONE REBOOT REQUIRED : NO REQUIRE APPLICATION DOWNTIME : YES PATCH INSTALLATION INSTRUCTIONS: -------------------------------- Please refer to Install Guide for install instructions and Release Notes for other information. PATCH UNINSTALLATION INSTRUCTIONS: ---------------------------------- Please refer to Install Guide for uninstall instructions and Release Notes for other information. SPECIAL INSTRUCTIONS: ----------------------------- NONE SUMMARY OF FIXED ISSUES: ----------------------------------------- PATCH ID:VRTSllt-6.2.1.000 3663730 (3567354) The Linux kernel panics when it receives a shared non-linear skb for linearization from the Low Latency Transport (LLT). 3663741 (3663740) In a rare scenario, divide by zero error is seen when lltshow -p command is run. SUMMARY OF KNOWN ISSUES: ----------------------------------------- NONE KNOWN ISSUES : -------------- NONE FIXED INCIDENTS: ---------------- PATCH ID:VRTSllt-6.2.1.000 * INCIDENT NO:3663730 TRACKING ID:3567354 SYMPTOM: Low Latency Transport (LLT) observes a kernel panic on receiving a shared non-linear skb. DESCRIPTION: When LLT receives a shared non-linear skb from the network driver, it passes the skb to the kernel for linearization. Since the skb is shared between multiple owners, the kernel cannot linearize it causing a system panic. RESOLUTION: The code is modified such that on receiving a non-linear skb, LLT validates if the skb is shared. If the validation is true, then the kernel clones the skb, returns the cloned skb to LLT, and decreases the reference count of the original skb. Further, LLT passes the cloned skb to the kernel for linearization. * INCIDENT NO:3663741 TRACKING ID:3663740 SYMPTOM: In a rare scenario, the system shows a divide by zero error and generates a core dump when lltshow -p command is run. DESCRIPTION: If a variable value becomes zero under certain conditions and lltshow p is run at the same time to get the port stats, the system shows a divide by zero error. RESOLUTION: The code is modified to skip printing the batch upcall latency average when the batch count is zero. INCIDENTS FROM OLD PATCHES: --------------------------- NONE