From mboxrd@z Thu Jan 1 00:00:00 1970 From: arnd@arndb.de (Arnd Bergmann) Date: Thu, 13 Nov 2014 23:25:29 +0100 Subject: [RFC] ptrace: add generic SET_SYSCALL request In-Reply-To: References: <1415346443-28915-1-git-send-email-takahiro.akashi@linaro.org> <3899236.yrOvvrZHD6@wuerfel> Message-ID: <1472197.o98pKNTkBz@wuerfel> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Thursday 13 November 2014 15:49:20 Ulrich Weigand wrote: > Arnd Bergmann wrote on 13.11.2014 11:21:28: > > > I have to admit that I don't really understand gdb internals, but from > > a first look I get the impression that it will just do the right thing > > if you reuse NT_S390_SYSTEM_CALL on ARM64 with the same semantics. > > There's an interface between BFD and GDB proper involved here. BFD will > detect the presence of register set notes in the core dump, and will > translate them into virtual sections; GDB will then simply look up such > sections under well-known names. > > In particular, the NT_S390_SYSTEM_CALL note will be translated by BFD > into a virtual section named ".reg-s390-system-call"; GDB platform- > specific code will look for sections of this particular name. > > So if you were to create notes using the same note type, by default it > would do nothing on ARM64. You might add code to the ARM64 back-end > to also look for a section ".reg-s390-system-call", but that would be > somewhat confusing. Using a new, platform-specific note type for ARM64 > would appear to fit better with existing precedent. Ok, thanks a lot for your insight and for confirming what Takahiro AKASHI said. Let's use a new NT_ARM64_SYSTEM_CALL type with a different number then. Arnd