From e4bb64c7a42e61bcb6f8b70279fc1f7805eaad3f Mon Sep 17 00:00:00 2001 From: Nicholas Piggin Date: Thu, 11 Feb 2021 16:36:36 +1000 Subject: [PATCH] powerpc: remove interrupt handler functions from the noinstr section The allyesconfig ppc64 kernel fails to link with relocations unable to fit after commit 3a96570ffceb ("powerpc: convert interrupt handlers to use wrappers"), which is due to the interrupt handler functions being put into the .noinstr.text section, which the linker script places on the opposite side of the main .text section from the interrupt entry asm code which calls the handlers. This results in a lot of linker stubs that overwhelm the 252-byte sized space we allow for them, or in the case of BE a .opd relocation link error for some reason. It's not required to put interrupt handlers in the .noinstr section, previously they used NOKPROBE_SYMBOL, so take them out and replace with a NOKPROBE_SYMBOL in the wrapper macro. Remove the explicit NOKPROBE_SYMBOL macros in the interrupt handler functions. This makes a number of interrupt handlers nokprobe that were not prior to the interrupt wrappers commit, but since that commit they were made nokprobe due to being in .noinstr.text, so this fix does not change that. The fixes tag is different to the commit that first exposes the problem because it is where the wrapper macros were introduced. Fixes: 8d41fc618ab8 ("powerpc: interrupt handler wrapper functions") Reported-by: Stephen Rothwell Signed-off-by: Nicholas Piggin [mpe: Slightly fix up comment wording] Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20210211063636.236420-1-npiggin@gmail.com --- arch/powerpc/include/asm/interrupt.h | 25 ++++++++++++++++++++----- arch/powerpc/kernel/traps.c | 9 --------- arch/powerpc/mm/fault.c | 1 - 3 files changed, 20 insertions(+), 15 deletions(-) diff --git a/arch/powerpc/include/asm/interrupt.h b/arch/powerpc/include/asm/interrupt.h index 4badb3e..5c28559 100644 --- a/arch/powerpc/include/asm/interrupt.h +++ b/arch/powerpc/include/asm/interrupt.h @@ -6,6 +6,7 @@ #include #include #include +#include #include struct interrupt_state { @@ -164,6 +165,15 @@ static inline void interrupt_nmi_exit_prepare(struct pt_regs *regs, struct inter #endif } +/* + * Don't use noinstr here like x86, but rather add NOKPROBE_SYMBOL to each + * function definition. The reason for this is the noinstr section is placed + * after the main text section, i.e., very far away from the interrupt entry + * asm. That creates problems with fitting linker stubs when building large + * kernels. + */ +#define interrupt_handler __visible noinline notrace __no_kcsan __no_sanitize_address + /** * DECLARE_INTERRUPT_HANDLER_RAW - Declare raw interrupt handler function * @func: Function name of the entry point @@ -198,7 +208,7 @@ static inline void interrupt_nmi_exit_prepare(struct pt_regs *regs, struct inter #define DEFINE_INTERRUPT_HANDLER_RAW(func) \ static __always_inline long ____##func(struct pt_regs *regs); \ \ -__visible noinstr long func(struct pt_regs *regs) \ +interrupt_handler long func(struct pt_regs *regs) \ { \ long ret; \ \ @@ -206,6 +216,7 @@ __visible noinstr long func(struct pt_regs *regs) \ \ return ret; \ } \ +NOKPROBE_SYMBOL(func); \ \ static __always_inline long ____##func(struct pt_regs *regs) @@ -228,7 +239,7 @@ static __always_inline long ____##func(struct pt_regs *regs) #define DEFINE_INTERRUPT_HANDLER(func) \ static __always_inline void ____##func(struct pt_regs *regs); \ \ -__visible noinstr void func(struct pt_regs *regs) \ +interrupt_handler void func(struct pt_regs *regs) \ { \ struct interrupt_state state; \ \ @@ -238,6 +249,7 @@ __visible noinstr void func(struct pt_regs *regs) \ \ interrupt_exit_prepare(regs, &state); \ } \ +NOKPROBE_SYMBOL(func); \ \ static __always_inline void ____##func(struct pt_regs *regs) @@ -262,7 +274,7 @@ static __always_inline void ____##func(struct pt_regs *regs) #define DEFINE_INTERRUPT_HANDLER_RET(func) \ static __always_inline long ____##func(struct pt_regs *regs); \ \ -__visible noinstr long func(struct pt_regs *regs) \ +interrupt_handler long func(struct pt_regs *regs) \ { \ struct interrupt_state state; \ long ret; \ @@ -275,6 +287,7 @@ __visible noinstr long func(struct pt_regs *regs) \ \ return ret; \ } \ +NOKPROBE_SYMBOL(func); \ \ static __always_inline long ____##func(struct pt_regs *regs) @@ -297,7 +310,7 @@ static __always_inline long ____##func(struct pt_regs *regs) #define DEFINE_INTERRUPT_HANDLER_ASYNC(func) \ static __always_inline void ____##func(struct pt_regs *regs); \ \ -__visible noinstr void func(struct pt_regs *regs) \ +interrupt_handler void func(struct pt_regs *regs) \ { \ struct interrupt_state state; \ \ @@ -307,6 +320,7 @@ __visible noinstr void func(struct pt_regs *regs) \ \ interrupt_async_exit_prepare(regs, &state); \ } \ +NOKPROBE_SYMBOL(func); \ \ static __always_inline void ____##func(struct pt_regs *regs) @@ -331,7 +345,7 @@ static __always_inline void ____##func(struct pt_regs *regs) #define DEFINE_INTERRUPT_HANDLER_NMI(func) \ static __always_inline long ____##func(struct pt_regs *regs); \ \ -__visible noinstr long func(struct pt_regs *regs) \ +interrupt_handler long func(struct pt_regs *regs) \ { \ struct interrupt_nmi_state state; \ long ret; \ @@ -344,6 +358,7 @@ __visible noinstr long func(struct pt_regs *regs) \ \ return ret; \ } \ +NOKPROBE_SYMBOL(func); \ \ static __always_inline long ____##func(struct pt_regs *regs) diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c index 39c8b7e..1583fd1 100644 --- a/arch/powerpc/kernel/traps.c +++ b/arch/powerpc/kernel/traps.c @@ -513,7 +513,6 @@ out: return 0; } -NOKPROBE_SYMBOL(system_reset_exception); /* * I/O accesses can cause machine checks on powermacs. @@ -798,7 +797,6 @@ void die_mce(const char *str, struct pt_regs *regs, long err) nmi_exit(); die(str, regs, err); } -NOKPROBE_SYMBOL(die_mce); /* * BOOK3S_64 does not call this handler as a non-maskable interrupt @@ -851,7 +849,6 @@ bail: return 0; #endif } -NOKPROBE_SYMBOL(machine_check_exception); DEFINE_INTERRUPT_HANDLER(SMIException) /* async? */ { @@ -1113,7 +1110,6 @@ DEFINE_INTERRUPT_HANDLER(single_step_exception) _exception(SIGTRAP, regs, TRAP_TRACE, regs->nip); } -NOKPROBE_SYMBOL(single_step_exception); /* * After we have successfully emulated an instruction, we have to @@ -1556,7 +1552,6 @@ DEFINE_INTERRUPT_HANDLER(program_check_exception) { do_program_check(regs); } -NOKPROBE_SYMBOL(program_check_exception); /* * This occurs when running in hypervisor mode on POWER6 or later @@ -1567,7 +1562,6 @@ DEFINE_INTERRUPT_HANDLER(emulation_assist_interrupt) regs->msr |= REASON_ILLEGAL; do_program_check(regs); } -NOKPROBE_SYMBOL(emulation_assist_interrupt); DEFINE_INTERRUPT_HANDLER(alignment_exception) { @@ -2034,7 +2028,6 @@ DEFINE_INTERRUPT_HANDLER(DebugException) } else handle_debug(regs, debug_status); } -NOKPROBE_SYMBOL(DebugException); #endif /* CONFIG_PPC_ADV_DEBUG_REGS */ #ifdef CONFIG_ALTIVEC @@ -2183,7 +2176,6 @@ DEFINE_INTERRUPT_HANDLER(unrecoverable_exception) regs->trap, regs->nip, regs->msr); die("Unrecoverable exception", regs, SIGABRT); } -NOKPROBE_SYMBOL(unrecoverable_exception); #if defined(CONFIG_BOOKE_WDT) || defined(CONFIG_40x) /* @@ -2214,7 +2206,6 @@ DEFINE_INTERRUPT_HANDLER(kernel_bad_stack) regs->gpr[1], regs->nip); die("Bad kernel stack pointer", regs, SIGABRT); } -NOKPROBE_SYMBOL(kernel_bad_stack); void __init trap_init(void) { diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c index b26a764..bb36825 100644 --- a/arch/powerpc/mm/fault.c +++ b/arch/powerpc/mm/fault.c @@ -566,7 +566,6 @@ DEFINE_INTERRUPT_HANDLER_RET(do_page_fault) { return __do_page_fault(regs); } -NOKPROBE_SYMBOL(do_page_fault); #ifdef CONFIG_PPC_BOOK3S_64 /* Same as do_page_fault but interrupt entry has already run in do_hash_fault */ -- 2.7.4