Impact: ureadahead can cause the kernel to allocate too much RAM for tracing on a hyper-threaded system.
Symptoms vary, but can result in an unbootable machine.
Patch Description: Count the number of CPUs and divide the amount allocated of trace buffer by that number.
ureadahead allocates trace buffers using 'echo 128000 > /sys/kernel/debug/tracing/buffer_size_kb". Since this is a per-CPU allocation, a multi-core system can end up allocating quite a lot of RAM.
SRU Justification
Impact: ureadahead can cause the kernel to allocate too much RAM for tracing on a hyper-threaded system.
Symptoms vary, but can result in an unbootable machine.
Patch Description: Count the number of CPUs and divide the amount allocated of trace buffer by that number. debug/tracing/ buffer_ size_kb" . Since this is a per-CPU allocation, a multi-core system can end up allocating quite a lot of RAM.
ureadahead allocates trace buffers using 'echo 128000 > /sys/kernel/
Patch: see attached