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KASAN_HW_TAGS are dependent on the HW implementation and are not reserved from system memory like shadow memory. Suggested-by: Andrey Konovalov Signed-off-by: Chanho Min Reviewed-by: Andrey Konovalov --- lib/Kconfig.kasan | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/lib/Kconfig.kasan b/lib/Kconfig.kasan index fdca89c05745..f8f9e12510b7 100644 --- a/lib/Kconfig.kasan +++ b/lib/Kconfig.kasan @@ -124,7 +124,8 @@ config KASAN_HW_TAGS Supported only on arm64 CPUs starting from ARMv8.5 and relies on Memory Tagging Extension and Top Byte Ignore. - Consumes about 1/32nd of available memory. + Does not consume memory by itself but relies on the 1/32nd of + available memory being reserved by the firmware when MTE is enabled. May potentially introduce problems related to pointer casting and comparison, as it embeds a tag into the top byte of each pointer.