From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id B7B4D3854826; Sat, 14 Nov 2020 09:06:42 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org B7B4D3854826 From: "robert at robertbuhren dot de" To: gdb-prs@sourceware.org Subject: [Bug gdb/26876] gdb error: internal-error: Unknown CFA rule when debugging the linux kernel with qemu Date: Sat, 14 Nov 2020 09:06:42 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gdb X-Bugzilla-Component: gdb X-Bugzilla-Version: 10.1 X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: robert at robertbuhren dot de X-Bugzilla-Status: NEW X-Bugzilla-Resolution: X-Bugzilla-Priority: P2 X-Bugzilla-Assigned-To: unassigned at sourceware dot org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: http://sourceware.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-BeenThere: gdb-prs@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gdb-prs mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 14 Nov 2020 09:06:42 -0000 https://sourceware.org/bugzilla/show_bug.cgi?id=3D26876 --- Comment #4 from robert at robertbuhren dot de --- Hi,=20 thanks for looking into this. I forgot to include my qemu setup, sorry for that. There is no need to use any kind of guest OS to trigger the bug: qemu-system-x86_64 -enable-kvm -m 4096 -smp 1 -kernel linux/arch/x86/boot/bzImage -append "console=3DttyS0 nokaslr" -S -s -nograp= hic -monitor tcp::4444,server,nowait -serial stdio I let the kernel boot (it will panic because there is no /init to execute) = and then simply stop it via "CTRL-C":=20 GNU gdb (GDB) 10.1 Copyright (C) 2020 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. Type "show copying" and "show warranty" for details. This GDB was configured as "x86_64-pc-linux-gnu". Type "show configuration" for configuration details. For bug reporting instructions, please see: . Find the GDB manual and other documentation resources online at: . For help, type "help". Type "apropos word" to search for commands related to "word". (gdb) file vmlinux Reading symbols from vmlinux... (gdb) tar rem :1234 Remote debugging using :1234 0x000000000000fff0 in exception_stacks () (gdb) c Continuing. ^C Program received signal SIGINT, Interrupt. 0xffffffff814222e0 in rdtsc_ordered () at ./arch/x86/include/asm/msr.h:234 234 asm volatile(ALTERNATIVE_2("rdtsc", (gdb) lx-symbols=20 loading vmlinux ../../gdb/dwarf2/frame.c:1085: internal-error: Unknown CFA rule. A problem internal to GDB has been detected, further debugging may prove unreliable. Quit this debugging session? (y or n) y This is a bug, please report it. For instructions, see: . ../../gdb/dwarf2/frame.c:1085: internal-error: Unknown CFA rule. A problem internal to GDB has been detected, further debugging may prove unreliable. Create a core file of GDB? (y or n) y fish: =E2=80=9Cgdb=E2=80=9D terminated by signal SIGABRT (Abort) Regards, Robert --=20 You are receiving this mail because: You are on the CC list for the bug.=