From patchwork Wed Aug 18 12:14:25 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dimitri John Ledkov X-Patchwork-Id: 1518009 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (no SPF record) smtp.mailfrom=lists.ubuntu.com (client-ip=91.189.94.19; helo=huckleberry.canonical.com; envelope-from=kernel-team-bounces@lists.ubuntu.com; receiver=) Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=canonical.com header.i=@canonical.com header.a=rsa-sha256 header.s=20210705 header.b=XXilcW6a; dkim-atps=neutral Received: from huckleberry.canonical.com (huckleberry.canonical.com [91.189.94.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 4GqRfp3CD3z9sWq; Wed, 18 Aug 2021 22:14:58 +1000 (AEST) Received: from localhost ([127.0.0.1] helo=huckleberry.canonical.com) by huckleberry.canonical.com with esmtp (Exim 4.86_2) (envelope-from ) id 1mGKT8-0005k7-U2; Wed, 18 Aug 2021 12:14:54 +0000 Received: from smtp-relay-canonical-0.internal ([10.131.114.83] helo=smtp-relay-canonical-0.canonical.com) by huckleberry.canonical.com with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.86_2) (envelope-from ) id 1mGKT3-0005iX-LJ for kernel-team@lists.ubuntu.com; Wed, 18 Aug 2021 12:14:49 +0000 Received: from mail-pg1-f197.google.com (mail-pg1-f197.google.com [209.85.215.197]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by smtp-relay-canonical-0.canonical.com (Postfix) with ESMTPS id 78B3D40CAC for ; Wed, 18 Aug 2021 12:14:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=canonical.com; s=20210705; t=1629288889; bh=MxOUqVWaCfQRJ60RDwf4pyKGJDmeb5nz9w+QnqwEuj4=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=XXilcW6a1I06YuQnfrkuXhc9N/KnRY0O1RPHA9QJyl5RnGpSo2fYEc1G93nF93h6v SJ22elhzoXmkduj86FqWB0VPAclorbTDEhTwUCftpy54sBVXqguiq7Gkne9B1k0oWT LoZNvMXTQi8nExtpKvCwAwo6+AVEB1ENX5kFvpqY5uibaZjZDImZns5uZliyyxk05B E9jKnO3Ia5rOs0L9ji0XStNGjUdtbGS8Jg6k7tAitnmcJJNI4QnMGaJtEuyaC+rsTC mUppX4jMTUWc+i6piZBRu23OiEWsNN6CYgVxpM3quk2UrdvEpeeECWvELbFV6f+hDZ Rms3+XoLOuhcQ== Received: by mail-pg1-f197.google.com with SMTP id t28-20020a63461c000000b00252078b83e4so1309456pga.15 for ; Wed, 18 Aug 2021 05:14:49 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=MxOUqVWaCfQRJ60RDwf4pyKGJDmeb5nz9w+QnqwEuj4=; b=HUVSVbL+lbBfxCNlrzCLL5XcX/8c+8BcHaoVqNq5vBeZ43r9OJwb1Tee+Zmq1FUeCJ C5dZEFeSzV4DGHfinIGhbVbfuW/KRmLKiIJKWPoeTLp795E1wUgnQ60xbGv0A/zNdHz/ IMuzm2EaLii66rPaVwY2/K20QCb5LEUc1CDFT+4REbpZZN8jZpl+Jt8sGI+bBGsXFSDY Da2Ip93MWNsT0pf1O9sIaSRT4bHb1E2ImWhyHwIJbmHObHM3CbJksXoCX7UdwtvQfAaE 0XBGY+KLTOuR7Tmhv4vLXhJ6SHCq0/JEqg87GIcpvYVZ0qCa8dzQxg1XLy9T5/ZhPbeN batQ== X-Gm-Message-State: AOAM5311ccxqxfx8CeDYjpjaoaJwbie0jBcD9YgOiB/qwdEYOn6rnx/J uXmXBYdujGOjBUw5Xg1pLIatMppw96hLl/QKH/ZKE6b0TQMcPoZCrkd3XooKqeFqBzyx/885CHk HoxR+ov5u1xaxju0u3CtM/55mkhnHIUbvlfhikam12w== X-Received: by 2002:a65:6910:: with SMTP id s16mr8654789pgq.270.1629288887935; Wed, 18 Aug 2021 05:14:47 -0700 (PDT) X-Google-Smtp-Source: ABdhPJx1tL4xoJxwYW/3EfLiF/CeK6wbUWv+o+dN7PeX+32lgosJr1DwgH7XaliidOn+js0bDXC0CA== X-Received: by 2002:a65:6910:: with SMTP id s16mr8654778pgq.270.1629288887713; Wed, 18 Aug 2021 05:14:47 -0700 (PDT) Received: from localhost ([2a01:4b00:85fd:d700:1397:609:e787:2244]) by smtp.gmail.com with ESMTPSA id x12sm6133804pfu.21.2021.08.18.05.14.46 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 18 Aug 2021 05:14:47 -0700 (PDT) From: Dimitri John Ledkov To: kernel-team@lists.ubuntu.com Subject: [HIRSUTE][linux-riscv][PATCH v2 2/3] riscv: Fixup patch_text panic in ftrace Date: Wed, 18 Aug 2021 13:14:25 +0100 Message-Id: <20210818121426.195205-3-dimitri.ledkov@canonical.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210818121426.195205-1-dimitri.ledkov@canonical.com> References: <20210818121426.195205-1-dimitri.ledkov@canonical.com> MIME-Version: 1.0 X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.20 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: cascardo@canonical.com Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: "kernel-team" From: Guo Ren Just like arm64, we can't trace the function in the patch_text path. Here is the bug log: [ 45.234334] Unable to handle kernel paging request at virtual address ffffffd38ae80900 [ 45.242313] Oops [#1] [ 45.244600] Modules linked in: [ 45.247678] CPU: 0 PID: 11 Comm: migration/0 Not tainted 5.9.0-00025-g9b7db83-dirty #215 [ 45.255797] epc: ffffffe00021689a ra : ffffffe00021718e sp : ffffffe01afabb58 [ 45.262955] gp : ffffffe00136afa0 tp : ffffffe01af94d00 t0 : 0000000000000002 [ 45.270200] t1 : 0000000000000000 t2 : 0000000000000001 s0 : ffffffe01afabc08 [ 45.277443] s1 : ffffffe0013718a8 a0 : 0000000000000000 a1 : ffffffe01afabba8 [ 45.284686] a2 : 0000000000000000 a3 : 0000000000000000 a4 : c4c16ad38ae80900 [ 45.291929] a5 : 0000000000000000 a6 : 0000000000000000 a7 : 0000000052464e43 [ 45.299173] s2 : 0000000000000001 s3 : ffffffe000206a60 s4 : ffffffe000206a60 [ 45.306415] s5 : 00000000000009ec s6 : ffffffe0013718a8 s7 : c4c16ad38ae80900 [ 45.313658] s8 : 0000000000000004 s9 : 0000000000000001 s10: 0000000000000001 [ 45.320902] s11: 0000000000000003 t3 : 0000000000000001 t4 : ffffffffd192fe79 [ 45.328144] t5 : ffffffffb8f80000 t6 : 0000000000040000 [ 45.333472] status: 0000000200000100 badaddr: ffffffd38ae80900 cause: 000000000000000f [ 45.341514] ---[ end trace d95102172248fdcf ]--- [ 45.346176] note: migration/0[11] exited with preempt_count 1 (gdb) x /2i $pc => 0xffffffe00021689a <__do_proc_dointvec+196>: sd zero,0(s7) 0xffffffe00021689e <__do_proc_dointvec+200>: li s11,0 (gdb) bt 0 __do_proc_dointvec (tbl_data=0x0, table=0xffffffe01afabba8, write=0, buffer=0x0, lenp=0x7bf897061f9a0800, ppos=0x4, conv=0x0, data=0x52464e43) at kernel/sysctl.c:581 1 0xffffffe00021718e in do_proc_dointvec (data=, conv=, ppos=, lenp=, buffer=, write=, table=) at kernel/sysctl.c:964 2 proc_dointvec_minmax (ppos=, lenp=, buffer=, write=, table=) at kernel/sysctl.c:964 3 proc_do_static_key (table=, write=1, buffer=0x0, lenp=0x0, ppos=0x7bf897061f9a0800) at kernel/sysctl.c:1643 4 0xffffffe000206792 in ftrace_make_call (rec=, addr=) at arch/riscv/kernel/ftrace.c:109 5 0xffffffe0002c9c04 in __ftrace_replace_code (rec=0xffffffe01ae40c30, enable=3) at kernel/trace/ftrace.c:2503 6 0xffffffe0002ca0b2 in ftrace_replace_code (mod_flags=) at kernel/trace/ftrace.c:2530 7 0xffffffe0002ca26a in ftrace_modify_all_code (command=5) at kernel/trace/ftrace.c:2677 8 0xffffffe0002ca30e in __ftrace_modify_code (data=) at kernel/trace/ftrace.c:2703 9 0xffffffe0002c13b0 in multi_cpu_stop (data=0x0) at kernel/stop_machine.c:224 10 0xffffffe0002c0fde in cpu_stopper_thread (cpu=) at kernel/stop_machine.c:491 11 0xffffffe0002343de in smpboot_thread_fn (data=0x0) at kernel/smpboot.c:165 12 0xffffffe00022f8b4 in kthread (_create=0xffffffe01af0c040) at kernel/kthread.c:292 13 0xffffffe000201fac in handle_exception () at arch/riscv/kernel/entry.S:236 0xffffffe00020678a <+114>: auipc ra,0xffffe 0xffffffe00020678e <+118>: jalr -118(ra) # 0xffffffe000204714 0xffffffe000206792 <+122>: snez a0,a0 (gdb) disassemble patch_text_nosync Dump of assembler code for function patch_text_nosync: 0xffffffe000204714 <+0>: addi sp,sp,-32 0xffffffe000204716 <+2>: sd s0,16(sp) 0xffffffe000204718 <+4>: sd ra,24(sp) 0xffffffe00020471a <+6>: addi s0,sp,32 0xffffffe00020471c <+8>: auipc ra,0x0 0xffffffe000204720 <+12>: jalr -384(ra) # 0xffffffe00020459c 0xffffffe000204724 <+16>: beqz a0,0xffffffe00020472e 0xffffffe000204726 <+18>: ld ra,24(sp) 0xffffffe000204728 <+20>: ld s0,16(sp) 0xffffffe00020472a <+22>: addi sp,sp,32 0xffffffe00020472c <+24>: ret 0xffffffe00020472e <+26>: sd a0,-24(s0) 0xffffffe000204732 <+30>: auipc ra,0x4 0xffffffe000204736 <+34>: jalr -1464(ra) # 0xffffffe00020817a 0xffffffe00020473a <+38>: ld a0,-24(s0) 0xffffffe00020473e <+42>: ld ra,24(sp) 0xffffffe000204740 <+44>: ld s0,16(sp) 0xffffffe000204742 <+46>: addi sp,sp,32 0xffffffe000204744 <+48>: ret (gdb) disassemble flush_icache_all-4 Dump of assembler code for function flush_icache_all: 0xffffffe00020817a <+0>: addi sp,sp,-8 0xffffffe00020817c <+2>: sd ra,0(sp) 0xffffffe00020817e <+4>: auipc ra,0xfffff 0xffffffe000208182 <+8>: jalr -1822(ra) # 0xffffffe000206a60 0xffffffe000208186 <+12>: ld ra,0(sp) 0xffffffe000208188 <+14>: addi sp,sp,8 0xffffffe00020818a <+0>: addi sp,sp,-16 0xffffffe00020818c <+2>: sd s0,0(sp) 0xffffffe00020818e <+4>: sd ra,8(sp) 0xffffffe000208190 <+6>: addi s0,sp,16 0xffffffe000208192 <+8>: li a0,0 0xffffffe000208194 <+10>: auipc ra,0xfffff 0xffffffe000208198 <+14>: jalr -410(ra) # 0xffffffe000206ffa 0xffffffe00020819c <+18>: ld s0,0(sp) 0xffffffe00020819e <+20>: ld ra,8(sp) 0xffffffe0002081a0 <+22>: addi sp,sp,16 0xffffffe0002081a2 <+24>: ret (gdb) frame 5 (rec=0xffffffe01ae40c30, enable=3) at kernel/trace/ftrace.c:2503 2503 return ftrace_make_call(rec, ftrace_addr); (gdb) p /x rec->ip $2 = 0xffffffe00020817a -> flush_icache_all ! When we modified flush_icache_all's patchable-entry with ftrace_caller: - Insert ftrace_caller at flush_icache_all prologue. - Call flush_icache_all to sync I/Dcache, but flush_icache_all is just we modified by half. Link: https://lore.kernel.org/linux-riscv/CAJF2gTT=oDWesWe0JVWvTpGi60-gpbNhYLdFWN_5EbyeqoEDdw@mail.gmail.com/T/#t Signed-off-by: Guo Ren Reviewed-by: Atish Patra Signed-off-by: Palmer Dabbelt (cherry picked from commit 5ad84adf5456313e285734102367c861c436c5ed) BugLink: https://bugs.launchpad.net/bugs/1940426 Signed-off-by: Dimitri John Ledkov --- arch/riscv/kernel/Makefile | 1 + arch/riscv/mm/Makefile | 1 + 2 files changed, 2 insertions(+) diff --git a/arch/riscv/kernel/Makefile b/arch/riscv/kernel/Makefile index 22c66dde18..4eee315d79 100644 --- a/arch/riscv/kernel/Makefile +++ b/arch/riscv/kernel/Makefile @@ -6,6 +6,7 @@ ifdef CONFIG_FTRACE CFLAGS_REMOVE_ftrace.o = $(CC_FLAGS_FTRACE) CFLAGS_REMOVE_patch.o = $(CC_FLAGS_FTRACE) +CFLAGS_REMOVE_sbi.o = $(CC_FLAGS_FTRACE) endif extra-y += head.o diff --git a/arch/riscv/mm/Makefile b/arch/riscv/mm/Makefile index 6b4b7ec1bd..7ebaef10ea 100644 --- a/arch/riscv/mm/Makefile +++ b/arch/riscv/mm/Makefile @@ -3,6 +3,7 @@ CFLAGS_init.o := -mcmodel=medany ifdef CONFIG_FTRACE CFLAGS_REMOVE_init.o = $(CC_FLAGS_FTRACE) +CFLAGS_REMOVE_cacheflush.o = $(CC_FLAGS_FTRACE) endif KCOV_INSTRUMENT_init.o := n