Job description:
Linux Kernel Driver Engineer (Filesystem / VFS)
Location: Pune, MH or Gandhinagar, GJ
Experience: 5–10 years
Employment Type: Full-time
Reports To: Everest Linux Platform Architect
About the Role
We are looking for a Linux Kernel Engineer to develop and maintain kernel-mode driver (KMD), a DKMS-packaged loadable kernel module that hooks the VFS layer to transparently intercept file operations, manage stub files, and enable seamless cloud tiering of surveillance video — without modifying the VMS or requiring embedded NVR/DVR hardware.
Key Responsibilities
- Design, implement, and maintain a Linux kernel module (LKM) built and distributed via DKMS across supported Ubuntu Server kernel versions
- Implement and evolve VFS-layer hooks covering inode, dentry, and superblock operations, and core filesystem entry points (open, read, getattr, etc.)
- Use kprobes/kretprobes (e.g. on vfs_getattr_nosec) to intercept and modify kernel behavior for stub-file size reporting without breaking VMS retention logic
- Own kernel-side synchronization (spinlocks, mutexes, RCU where applicable) across concurrent file access paths
- Debug kernel-level issues using dmesg, ftrace, crash/kdump, and /proc / /sys inspection; verify module identity via srcversion after every change
- Coordinate the kernel/userspace boundary (shared memory, ring buffers) with the Linux Systems Programming team
- Maintain strict versioning discipline (module version, module params) and produce round-numbered RCA design docs for significant fixes
Mandatory Skills
Must-Have
- Linux kernel module (LKM) development in C, packaged and distributed via DKMS
- Deep working knowledge of the VFS layer: inode, dentry, superblock, file_operations
- Experience with kprobes/kretprobes or equivalent dynamic kernel instrumentation techniques
- Filesystem driver / stackable filesystem concepts and standard entry points (open, read, write, getattr, release)
- Kernel debugging proficiency: dmesg, ftrace, crash/kdump, /proc and /sys inspection
- Solid grasp of kernel-space synchronization primitives (spinlocks, mutexes, RCU) and IRQ/atomic-context constraints
- Familiarity with kernel module versioning, signing, and safe load/unload lifecycle management
Nice-to-Have Skills
Good-to-Have
- FUSE internals knowledge, to reason about the kernel/userspace split cleanly
- eBPF programming experience
- Familiarity with mainstream filesystem internals (ext4, overlayfs, btrfs)
- Prior experience on backup, antivirus, or hierarchical-storage-management (HSM) kernel drivers
