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/hexagon/lib/memset.S | 302 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 302 insertions(+) create mode 100644 arch/hexagon/lib/memset.S (limited to 'arch/hexagon/lib/memset.S') diff --git a/arch/hexagon/lib/memset.S b/arch/hexagon/lib/memset.S new file mode 100644 index 000000000..e67304e3f --- /dev/null +++ b/arch/hexagon/lib/memset.S @@ -0,0 +1,302 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (c) 2011, The Linux Foundation. All rights reserved. + */ + + +/* HEXAGON assembly optimized memset */ +/* Replaces the standard library function memset */ + + + .macro HEXAGON_OPT_FUNC_BEGIN name + .text + .p2align 4 + .globl \name + .type \name, @function +\name: + .endm + + .macro HEXAGON_OPT_FUNC_FINISH name + .size \name, . - \name + .endm + +/* FUNCTION: memset (v2 version) */ +#if __HEXAGON_ARCH__ < 3 +HEXAGON_OPT_FUNC_BEGIN memset + { + r6 = #8 + r7 = extractu(r0, #3 , #0) + p0 = cmp.eq(r2, #0) + p1 = cmp.gtu(r2, #7) + } + { + r4 = vsplatb(r1) + r8 = r0 /* leave r0 intact for return val */ + r9 = sub(r6, r7) /* bytes until double alignment */ + if p0 jumpr r31 /* count == 0, so return */ + } + { + r3 = #0 + r7 = #0 + p0 = tstbit(r9, #0) + if p1 jump 2f /* skip byte loop */ + } + +/* less than 8 bytes to set, so just set a byte at a time and return */ + + loop0(1f, r2) /* byte loop */ + .falign +1: /* byte loop */ + { + memb(r8++#1) = r4 + }:endloop0 + jumpr r31 + .falign +2: /* skip byte loop */ + { + r6 = #1 + p0 = tstbit(r9, #1) + p1 = cmp.eq(r2, #1) + if !p0 jump 3f /* skip initial byte store */ + } + { + memb(r8++#1) = r4 + r3:2 = sub(r3:2, r7:6) + if p1 jumpr r31 + } + .falign +3: /* skip initial byte store */ + { + r6 = #2 + p0 = tstbit(r9, #2) + p1 = cmp.eq(r2, #2) + if !p0 jump 4f /* skip initial half store */ + } + { + memh(r8++#2) = r4 + r3:2 = sub(r3:2, r7:6) + if p1 jumpr r31 + } + .falign +4: /* skip initial half store */ + { + r6 = #4 + p0 = cmp.gtu(r2, #7) + p1 = cmp.eq(r2, #4) + if !p0 jump 5f /* skip initial word store */ + } + { + memw(r8++#4) = r4 + r3:2 = sub(r3:2, r7:6) + p0 = cmp.gtu(r2, #11) + if p1 jumpr r31 + } + .falign +5: /* skip initial word store */ + { + r10 = lsr(r2, #3) + p1 = cmp.eq(r3, #1) + if !p0 jump 7f /* skip double loop */ + } + { + r5 = r4 + r6 = #8 + loop0(6f, r10) /* double loop */ + } + +/* set bytes a double word at a time */ + + .falign +6: /* double loop */ + { + memd(r8++#8) = r5:4 + r3:2 = sub(r3:2, r7:6) + p1 = cmp.eq(r2, #8) + }:endloop0 + .falign +7: /* skip double loop */ + { + p0 = tstbit(r2, #2) + if p1 jumpr r31 + } + { + r6 = #4 + p0 = tstbit(r2, #1) + p1 = cmp.eq(r2, #4) + if !p0 jump 8f /* skip final word store */ + } + { + memw(r8++#4) = r4 + r3:2 = sub(r3:2, r7:6) + if p1 jumpr r31 + } + .falign +8: /* skip final word store */ + { + p1 = cmp.eq(r2, #2) + if !p0 jump 9f /* skip final half store */ + } + { + memh(r8++#2) = r4 + if p1 jumpr r31 + } + .falign +9: /* skip final half store */ + { + memb(r8++#1) = r4 + jumpr r31 + } +HEXAGON_OPT_FUNC_FINISH memset +#endif + + +/* FUNCTION: memset (v3 and higher version) */ +#if __HEXAGON_ARCH__ >= 3 +HEXAGON_OPT_FUNC_BEGIN memset + { + r7=vsplatb(r1) + r6 = r0 + if (r2==#0) jump:nt .L1 + } + { + r5:4=combine(r7,r7) + p0 = cmp.gtu(r2,#8) + if (p0.new) jump:nt .L3 + } + { + r3 = r0 + loop0(.L47,r2) + } + .falign +.L47: + { + memb(r3++#1) = r1 + }:endloop0 /* start=.L47 */ + jumpr r31 +.L3: + { + p0 = tstbit(r0,#0) + if (!p0.new) jump:nt .L8 + p1 = cmp.eq(r2, #1) + } + { + r6 = add(r0, #1) + r2 = add(r2,#-1) + memb(r0) = r1 + if (p1) jump .L1 + } +.L8: + { + p0 = tstbit(r6,#1) + if (!p0.new) jump:nt .L10 + } + { + r2 = add(r2,#-2) + memh(r6++#2) = r7 + p0 = cmp.eq(r2, #2) + if (p0.new) jump:nt .L1 + } +.L10: + { + p0 = tstbit(r6,#2) + if (!p0.new) jump:nt .L12 + } + { + r2 = add(r2,#-4) + memw(r6++#4) = r7 + p0 = cmp.eq(r2, #4) + if (p0.new) jump:nt .L1 + } +.L12: + { + p0 = cmp.gtu(r2,#127) + if (!p0.new) jump:nt .L14 + } + r3 = and(r6,#31) + if (r3==#0) jump:nt .L17 + { + memd(r6++#8) = r5:4 + r2 = add(r2,#-8) + } + r3 = and(r6,#31) + if (r3==#0) jump:nt .L17 + { + memd(r6++#8) = r5:4 + r2 = add(r2,#-8) + } + r3 = and(r6,#31) + if (r3==#0) jump:nt .L17 + { + memd(r6++#8) = r5:4 + r2 = add(r2,#-8) + } +.L17: + { + r3 = lsr(r2,#5) + if (r1!=#0) jump:nt .L18 + } + { + r8 = r3 + r3 = r6 + loop0(.L46,r3) + } + .falign +.L46: + { + dczeroa(r6) + r6 = add(r6,#32) + r2 = add(r2,#-32) + }:endloop0 /* start=.L46 */ +.L14: + { + p0 = cmp.gtu(r2,#7) + if (!p0.new) jump:nt .L28 + r8 = lsr(r2,#3) + } + loop0(.L44,r8) + .falign +.L44: + { + memd(r6++#8) = r5:4 + r2 = add(r2,#-8) + }:endloop0 /* start=.L44 */ +.L28: + { + p0 = tstbit(r2,#2) + if (!p0.new) jump:nt .L33 + } + { + r2 = add(r2,#-4) + memw(r6++#4) = r7 + } +.L33: + { + p0 = tstbit(r2,#1) + if (!p0.new) jump:nt .L35 + } + { + r2 = add(r2,#-2) + memh(r6++#2) = r7 + } +.L35: + p0 = cmp.eq(r2,#1) + if (p0) memb(r6) = r1 +.L1: + jumpr r31 +.L18: + loop0(.L45,r3) + .falign +.L45: + dczeroa(r6) + { + memd(r6++#8) = r5:4 + r2 = add(r2,#-32) + } + memd(r6++#8) = r5:4 + memd(r6++#8) = r5:4 + { + memd(r6++#8) = r5:4 + }:endloop0 /* start=.L45 */ + jump .L14 +HEXAGON_OPT_FUNC_FINISH memset +#endif -- cgit v1.3.1