This is a note to let you know that I've just added the patch titled powerpc: Only include kup-radix.h for 64-bit Book3S to the 5.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: powerpc-only-include-kup-radix.h-for-64-bit-book3s.patch and it can be found in the queue-5.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From foo@baz Fri Nov 20 08:16:31 AM CET 2020 From: Daniel Axtens <dja@xxxxxxxxxx> Date: Fri, 20 Nov 2020 10:35:15 +1100 Subject: powerpc: Only include kup-radix.h for 64-bit Book3S To: stable@xxxxxxxxxxxxxxx Cc: dja@xxxxxxxxxx Message-ID: <20201119233516.368194-5-dja@xxxxxxxxxx> From: Michael Ellerman <mpe@xxxxxxxxxxxxxx> commit 178d52c6e89c38d0553b0ac8b99927b11eb995b0 upstream. In kup.h we currently include kup-radix.h for all 64-bit builds, which includes Book3S and Book3E. The latter doesn't make sense, Book3E never uses the Radix MMU. This has worked up until now, but almost by accident, and the recent uaccess flush changes introduced a build breakage on Book3E because of the bad structure of the code. So disentangle things so that we only use kup-radix.h for Book3S. This requires some more stubs in kup.h. Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Signed-off-by: Daniel Axtens <dja@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/powerpc/include/asm/book3s/64/kup-radix.h | 5 +++-- arch/powerpc/include/asm/kup.h | 14 +++++++++++--- 2 files changed, 14 insertions(+), 5 deletions(-) --- a/arch/powerpc/include/asm/book3s/64/kup-radix.h +++ b/arch/powerpc/include/asm/book3s/64/kup-radix.h @@ -11,13 +11,12 @@ #ifdef __ASSEMBLY__ -.macro kuap_restore_amr gpr #ifdef CONFIG_PPC_KUAP +.macro kuap_restore_amr gpr BEGIN_MMU_FTR_SECTION_NESTED(67) ld \gpr, STACK_REGS_KUAP(r1) mtspr SPRN_AMR, \gpr END_MMU_FTR_SECTION_NESTED_IFSET(MMU_FTR_RADIX_KUAP, 67) -#endif .endm .macro kuap_check_amr gpr1, gpr2 @@ -31,6 +30,7 @@ END_MMU_FTR_SECTION_NESTED_IFSET(MMU_FTR_RADIX_KUAP, 67) #endif .endm +#endif .macro kuap_save_amr_and_lock gpr1, gpr2, use_cr, msr_pr_cr #ifdef CONFIG_PPC_KUAP @@ -87,6 +87,7 @@ bad_kuap_fault(struct pt_regs *regs, uns "Bug: %s fault blocked by AMR!", is_write ? "Write" : "Read"); } #else /* CONFIG_PPC_KUAP */ +static inline void kuap_restore_amr(struct pt_regs *regs, unsigned long amr) { } static inline void set_kuap(unsigned long value) { } #endif /* !CONFIG_PPC_KUAP */ --- a/arch/powerpc/include/asm/kup.h +++ b/arch/powerpc/include/asm/kup.h @@ -6,7 +6,7 @@ #define KUAP_WRITE 2 #define KUAP_READ_WRITE (KUAP_READ | KUAP_WRITE) -#ifdef CONFIG_PPC64 +#ifdef CONFIG_PPC_BOOK3S_64 #include <asm/book3s/64/kup-radix.h> #endif #ifdef CONFIG_PPC_8xx @@ -24,9 +24,15 @@ .macro kuap_restore sp, current, gpr1, gpr2, gpr3 .endm +.macro kuap_restore_amr gpr +.endm + .macro kuap_check current, gpr .endm +.macro kuap_check_amr gpr1, gpr2 +.endm + #endif #else /* !__ASSEMBLY__ */ @@ -52,17 +58,19 @@ bad_kuap_fault(struct pt_regs *regs, uns return false; } +static inline void kuap_check_amr(void) { } + /* * book3s/64/kup-radix.h defines these functions for the !KUAP case to flush * the L1D cache after user accesses. Only include the empty stubs for other * platforms. */ -#ifndef CONFIG_PPC64 +#ifndef CONFIG_PPC_BOOK3S_64 static inline void allow_user_access(void __user *to, const void __user *from, unsigned long size, unsigned long dir) { } static inline void prevent_user_access(void __user *to, const void __user *from, unsigned long size, unsigned long dir) { } -#endif /* CONFIG_PPC64 */ +#endif /* CONFIG_PPC_BOOK3S_64 */ #endif /* CONFIG_PPC_KUAP */ static inline void allow_read_from_user(const void __user *from, unsigned long size) Patches currently in stable-queue which might be from dja@xxxxxxxxxx are queue-5.4/selftests-powerpc-rfi_flush-disable-entry-flush-if-present.patch queue-5.4/powerpc-64s-flush-l1d-after-user-accesses.patch queue-5.4/selftests-powerpc-entry-flush-test.patch queue-5.4/powerpc-64s-flush-l1d-on-kernel-entry.patch queue-5.4/powerpc-only-include-kup-radix.h-for-64-bit-book3s.patch