From 4617721c502b2ddaa4e324e86da4997edf738fa5 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Wed, 2 Sep 2026 09:55:01 -0400 Subject: ftrace: Synchronize the initialization of ftrace_ops There's some internal state that ftrace_ops needs to have set, but since it can be declared outside of the ftrace.c code, it calls ftrace_ops_init() on the ops in every global function. The issue is that if two tasks call it on the same ops at the same time it is possible to have the initialization of one corrupt the initialization of the other call. Create a ops_mutex to use to synchronize every initialization of the ftrace_ops. The mutex is taken within checking the ftrace_ops flag that states it was initializied but the flag is checked again after the mutex has been taken. Checking first outside the mutex allows it to shortcut having to take the mutex. But then the check needs to be done again after the mute is taken in case of races. Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260902095501.6b59af20@gandalf.local.home Fixes: f04f24fb7e48d ("ftrace, kprobes: Fix a deadlock on ftrace_regex_lock") Reported-by: sashiko-bot@kernel.org Close: https://lore.kernel.org/all/20260829025528.49A831F000E9@smtp.kernel.org/ Signed-off-by: Steven Rostedt --- arch/powerpc/boot/gamecube-head.S | 106 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 106 insertions(+) create mode 100644 arch/powerpc/boot/gamecube-head.S (limited to 'arch/powerpc/boot/gamecube-head.S') diff --git a/arch/powerpc/boot/gamecube-head.S b/arch/powerpc/boot/gamecube-head.S new file mode 100644 index 000000000..ccf5f1045 --- /dev/null +++ b/arch/powerpc/boot/gamecube-head.S @@ -0,0 +1,106 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * arch/powerpc/boot/gamecube-head.S + * + * Nintendo GameCube bootwrapper entry. + * Copyright (C) 2004-2009 The GameCube Linux Team + * Copyright (C) 2008,2009 Albert Herranz + */ + +#include "ppc_asm.h" + +/* + * The entry code does no assumptions regarding: + * - if the data and instruction caches are enabled or not + * - if the MMU is enabled or not + * + * We enable the caches if not already enabled, enable the MMU with an + * identity mapping scheme and jump to the start code. + */ + + .text + + .globl _zimage_start +_zimage_start: + + /* turn the MMU off */ + mfmsr 9 + rlwinm 9, 9, 0, ~((1<<4)|(1<<5)) /* MSR_DR|MSR_IR */ + bcl 20, 31, 1f +1: + mflr 8 + clrlwi 8, 8, 3 /* convert to a real address */ + addi 8, 8, _mmu_off - 1b + mtsrr0 8 + mtsrr1 9 + rfi +_mmu_off: + /* MMU disabled */ + + /* setup BATs */ + isync + li 8, 0 + mtspr 0x210, 8 /* IBAT0U */ + mtspr 0x212, 8 /* IBAT1U */ + mtspr 0x214, 8 /* IBAT2U */ + mtspr 0x216, 8 /* IBAT3U */ + mtspr 0x218, 8 /* DBAT0U */ + mtspr 0x21a, 8 /* DBAT1U */ + mtspr 0x21c, 8 /* DBAT2U */ + mtspr 0x21e, 8 /* DBAT3U */ + + li 8, 0x01ff /* first 16MiB */ + li 9, 0x0002 /* rw */ + mtspr 0x211, 9 /* IBAT0L */ + mtspr 0x210, 8 /* IBAT0U */ + mtspr 0x219, 9 /* DBAT0L */ + mtspr 0x218, 8 /* DBAT0U */ + + lis 8, 0x0c00 /* I/O mem */ + ori 8, 8, 0x3ff /* 32MiB */ + lis 9, 0x0c00 + ori 9, 9, 0x002a /* uncached, guarded, rw */ + mtspr 0x21b, 9 /* DBAT1L */ + mtspr 0x21a, 8 /* DBAT1U */ + + lis 8, 0x0100 /* next 8MiB */ + ori 8, 8, 0x00ff /* 8MiB */ + lis 9, 0x0100 + ori 9, 9, 0x0002 /* rw */ + mtspr 0x215, 9 /* IBAT2L */ + mtspr 0x214, 8 /* IBAT2U */ + mtspr 0x21d, 9 /* DBAT2L */ + mtspr 0x21c, 8 /* DBAT2U */ + + /* enable and invalidate the caches if not already enabled */ + mfspr 8, 0x3f0 /* HID0 */ + andi. 0, 8, (1<<15) /* HID0_ICE */ + bne 1f + ori 8, 8, (1<<15)|(1<<11) /* HID0_ICE|HID0_ICFI*/ +1: + andi. 0, 8, (1<<14) /* HID0_DCE */ + bne 1f + ori 8, 8, (1<<14)|(1<<10) /* HID0_DCE|HID0_DCFI*/ +1: + mtspr 0x3f0, 8 /* HID0 */ + isync + + /* initialize arguments */ + li 3, 0 + li 4, 0 + li 5, 0 + + /* turn the MMU on */ + bcl 20, 31, 1f +1: + mflr 8 + addi 8, 8, _mmu_on - 1b + mfmsr 9 + ori 9, 9, (1<<4)|(1<<5) /* MSR_DR|MSR_IR */ + mtsrr0 8 + mtsrr1 9 + sync + rfi +_mmu_on: + b _zimage_start_lib + -- cgit v1.3.1