• Andrey Konovalov's avatar
    kasan: fix stack traces dependency for HW_TAGS · 1cc4cdb5
    Andrey Konovalov authored
    Currently, whether the alloc/free stack traces collection is enabled by
    default for hardware tag-based KASAN depends on CONFIG_DEBUG_KERNEL.
    The intention for this dependency was to only enable collection on slow
    debug kernels due to a significant perf and memory impact.
    
    As it turns out, CONFIG_DEBUG_KERNEL is not considered a debug option
    and is enabled on many productions kernels including Android and Ubuntu.
    As the result, this dependency is pointless and only complicates the
    code and documentation.
    
    Having stack traces collection disabled by default would make the
    hardware mode work differently to to the software ones, which is
    confusing.
    
    This change removes the dependency and enables stack traces collection
    by default.
    
    Looking into the future, this default might makes sense for production
    kernels, assuming we implement a fast stack trace collection approach.
    
    Link: https://lkml.kernel.org/r/6678d77ceffb71f1cff2cf61560e2ffe7bb6bfe9.1612808820.git.andreyknvl@google.comSigned-off-by: default avatarAndrey Konovalov <andreyknvl@google.com>
    Reviewed-by: default avatarMarco Elver <elver@google.com>
    Cc: Catalin Marinas <catalin.marinas@arm.com>
    Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
    Cc: Dmitry Vyukov <dvyukov@google.com>
    Cc: Alexander Potapenko <glider@google.com>
    Cc: Will Deacon <will.deacon@arm.com>
    Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
    Cc: Peter Collingbourne <pcc@google.com>
    Cc: Evgenii Stepanov <eugenis@google.com>
    Cc: Branislav Rankov <Branislav.Rankov@arm.com>
    Cc: Kevin Brodsky <kevin.brodsky@arm.com>
    Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    1cc4cdb5
kasan.rst 17.4 KB