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charset="UTF-8" X-Rspam-User: X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 7DB0C1C000A X-Stat-Signature: rsfug7fzxb698mt5t8mmh1m4dqabjnrp X-HE-Tag: 1675754378-215266 X-HE-Meta: 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 BamtMdPW Xm8a531PlELbbVjuxViU+ad/FdTdePRrm1hqccfd4Ljot4p4Ont+sMSKytYt3H8z4bkdYOVYOgzXh1ONrqGtH/rMvtjP+8HbXy8kzG71fAJIuToTQONtWnENRzGM0c+UTyrKRhqzo7Fcp2JDaUX2UYsvXWdYwRQjFKZhbymdSpdIFBonUp2ZXgp6NLO+TDYWkb4/1NdtXDSNuht9vFo5Xlqo8VEJmb7uu3UDjxMY1sKY3iUQYWlMIS8xDhyCag9o6CFHYx/lxJUPicqct2oiE+/lpol7s85XdSXCMKUtizMF18EEGdXELcI3jucAAtcyG3Sq7kBQUHvFx0h1r8V4YiWoAdhDtWHYK3zxlpe9V0GK5NV4cY95yoNdj3+s7ikCh5Vcs X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue, 7 Feb 2023 at 07:15, Zhenhua Huang wrote: > > Export the variable to ease the judgement of whether kfence enabled > at runtime. It should be more precise than through kernel config > "CONFIG_KFENCE". > > For example We can disable kfence at runtime using bootargs > "kfence.sample_interval=0" but CONFIG_KFENCE enabled. > It was false positive. > > Signed-off-by: Zhenhua Huang > --- > arch/arm64/mm/pageattr.c | 3 ++- > include/linux/kfence.h | 2 ++ > mm/kfence/core.c | 2 +- > 3 files changed, 5 insertions(+), 2 deletions(-) > > diff --git a/arch/arm64/mm/pageattr.c b/arch/arm64/mm/pageattr.c > index 79dd201..208d780 100644 > --- a/arch/arm64/mm/pageattr.c > +++ b/arch/arm64/mm/pageattr.c > @@ -7,6 +7,7 @@ > #include > #include > #include > +#include > > #include > #include > @@ -27,7 +28,7 @@ bool can_set_direct_map(void) > * protect/unprotect single pages. > */ > return (rodata_enabled && rodata_full) || debug_pagealloc_enabled() || > - IS_ENABLED(CONFIG_KFENCE); > + kfence_enabled; Unfortunately this won't work, because it's possible to enable KFENCE after the kernel has booted with e.g.: echo 100 > /sys/module/kfence/parameters/sample_interval What is the problem you have encountered? Is the page-granular direct map causing issues?