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No functional changes intended. > > Signed-off-by: Dmitry Vyukov > Cc: Mathieu Desnoyers > Cc: Peter Zijlstra > Cc: "Paul E. McKenney" > Cc: Boqun Feng > Cc: Thomas Gleixner > Cc: Ingo Molnar > Cc: Borislav Petkov > Cc: Dave Hansen > Cc: "H. Peter Anvin" > Cc: Aruna Ramakrishna > Cc: x86@kernel.org > Cc: linux-kernel@vger.kernel.org > > --- > Changes in v3: > - restore sig_prepare_pkru with the large comment and > make it call the new write_permissive_pkey_val > --- > arch/x86/kernel/signal.c | 6 ++---- > 1 file changed, 2 insertions(+), 4 deletions(-) > > diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c > index 5f441039b5725..27a66a0697dd2 100644 > --- a/arch/x86/kernel/signal.c > +++ b/arch/x86/kernel/signal.c > @@ -28,6 +28,7 @@ > #include > #include > #include > +#include > > #include > #include > @@ -72,10 +73,7 @@ static inline int is_x32_frame(struct ksignal *ksig) > */ > static inline u32 sig_prepare_pkru(void) > { > - u32 orig_pkru = read_pkru(); > - > - write_pkru(0); > - return orig_pkru; > + return write_permissive_pkey_val(); Reviewed-by: Mathieu Desnoyers Note that I would be curious to see if we could get away with changing this to enable_zero_pkey_val() without breaking any real-life user. AFAIU this would remove a WRPKRU from signal delivery, but would require the signal frames to be pkey-0, which is technically be a new ABI constraint never expressed before. Thanks, Mathieu > } > > /* -- Mathieu Desnoyers EfficiOS Inc. https://www.efficios.com