From 75c5d6b1e194c341371639469fcb8691afa0e254 Mon Sep 17 00:00:00 2001 From: Rohan McLure Date: Thu, 1 Dec 2022 18:10:15 +1100 Subject: [PATCH] powerpc/64: Sanitise common exit code for interrupts Interrupt code is shared between Book3E/S 64-bit systems for interrupt handlers. Ensure that exit code correctly restores non-volatile gprs on each system when CONFIG_INTERRUPT_SANITIZE_REGISTERS is enabled. Also introduce macros for clearing/restoring registers on interrupt entry for when this configuration option is either disabled or enabled. Reviewed-by: Nicholas Piggin Signed-off-by: Rohan McLure Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20221201071019.1953023-3-rmclure@linux.ibm.com --- arch/powerpc/kernel/interrupt_64.S | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/arch/powerpc/kernel/interrupt_64.S b/arch/powerpc/kernel/interrupt_64.S index 321992c1c9f90..dd04b0ba3959a 100644 --- a/arch/powerpc/kernel/interrupt_64.S +++ b/arch/powerpc/kernel/interrupt_64.S @@ -408,9 +408,11 @@ interrupt_return_\srr\()_user: /* make backtraces match the _kernel variant */ _ASM_NOKPROBE_SYMBOL(interrupt_return_\srr\()_user) addi r3,r1,STACK_INT_FRAME_REGS bl interrupt_exit_user_prepare +#ifndef CONFIG_INTERRUPT_SANITIZE_REGISTERS cmpdi r3,0 bne- .Lrestore_nvgprs_\srr .Lrestore_nvgprs_\srr\()_cont: +#endif std r1,PACA_EXIT_SAVE_R1(r13) /* save r1 for restart */ #ifdef CONFIG_PPC_BOOK3S .Linterrupt_return_\srr\()_user_rst_start: @@ -424,6 +426,7 @@ _ASM_NOKPROBE_SYMBOL(interrupt_return_\srr\()_user) stb r11,PACAIRQHAPPENED(r13) # clear out possible HARD_DIS .Lfast_user_interrupt_return_\srr\(): + SANITIZE_RESTORE_NVGPRS() #ifdef CONFIG_PPC_BOOK3S .ifc \srr,srr lbz r4,PACASRR_VALID(r13) @@ -493,9 +496,11 @@ ALT_FTR_SECTION_END_IFCLR(CPU_FTR_STCX_CHECKS_ADDRESS) b . /* prevent speculative execution */ .Linterrupt_return_\srr\()_user_rst_end: +#ifndef CONFIG_INTERRUPT_SANITIZE_REGISTERS .Lrestore_nvgprs_\srr\(): REST_NVGPRS(r1) b .Lrestore_nvgprs_\srr\()_cont +#endif #ifdef CONFIG_PPC_BOOK3S interrupt_return_\srr\()_user_restart: @@ -585,6 +590,7 @@ _ASM_NOKPROBE_SYMBOL(interrupt_return_\srr\()_kernel) stb r11,PACAIRQHAPPENED(r13) // clear the possible HARD_DIS .Lfast_kernel_interrupt_return_\srr\(): + SANITIZE_RESTORE_NVGPRS() cmpdi cr1,r3,0 #ifdef CONFIG_PPC_BOOK3S .ifc \srr,srr -- 2.30.2