From: Miroslav Benes <mbenes@suse.cz>
To: Torsten Duwe <duwe@lst.de>
Cc: Steven Rostedt <rostedt@goodmis.org>,
Michael Ellerman <mpe@ellerman.id.au>,
Jiri Kosina <jkosina@suse.cz>,
linuxppc-dev@lists.ozlabs.org,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
live-patching@vger.kernel.org, pmladek@suse.cz
Subject: Re: [PATCH v6 8/9] Implement kernel live patching for ppc64le (ABIv2)
Date: Tue, 26 Jan 2016 11:50:25 +0100 (CET) [thread overview]
Message-ID: <alpine.LNX.2.00.1601261142190.24510@pobox.suse.cz> (raw)
In-Reply-To: <20160125170804.A11DB692DD@newverein.lst.de>
[ added Petr to CC list ]
On Mon, 25 Jan 2016, Torsten Duwe wrote:
> * create the appropriate files+functions
> arch/powerpc/include/asm/livepatch.h
> klp_check_compiler_support,
> klp_arch_set_pc
> arch/powerpc/kernel/livepatch.c with a stub for
> klp_write_module_reloc
> This is architecture-independent work in progress.
> * introduce a fixup in arch/powerpc/kernel/entry_64.S
> for local calls that are becoming global due to live patching.
> And of course do the main KLP thing: return to a maybe different
> address, possibly altered by the live patching ftrace op.
>
> Signed-off-by: Torsten Duwe <duwe@suse.de>
Hi,
I have a few questions...
We still need Petr's patch from [1] to make livepatch work, right? Could
you, please, add it to this patch set to make it self-sufficient?
Second, what is the situation with mcount prologue between gcc < 6 and
gcc-6? Are there only 12 bytes in gcc-6 prologue? If yes, we need to
change Petr's patch to make it more general and to be able to cope with
different prologues. This is unfortunate. Either way, please mention it
somewhere in a changelog.
I haven't reviewed the patch properly yet, but there is a comment below.
[1] http://lkml.kernel.org/g/20151203160004.GE8047@pathway.suse.cz
> +/**
> + * klp_write_module_reloc() - write a relocation in a module
> + * @mod: module in which the section to be modified is found
> + * @type: ELF relocation type (see asm/elf.h)
> + * @loc: address that the relocation should be written to
> + * @value: relocation value (sym address + addend)
> + *
> + * This function writes a relocation to the specified location for
> + * a particular module.
> + */
> +int klp_write_module_reloc(struct module *mod, unsigned long type,
> + unsigned long loc, unsigned long value)
> +{
> + /* This requires infrastructure changes; we need the loadinfos. */
> + pr_err("lpc_write_module_reloc not yet supported\n");
This is a nit, but there is no lpc_write_module_reloc. It should be
klp_write_module_reloc.
Thanks,
Miroslav
next prev parent reply other threads:[~2016-01-26 10:50 UTC|newest]
Thread overview: 42+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-01-25 15:38 [PATCH v6 0/9] ftrace with regs + live patching for ppc64 LE (ABI v2) Torsten Duwe
2016-01-25 15:26 ` [PATCH v6 1/9] ppc64 (le): prepare for -mprofile-kernel Torsten Duwe
2016-01-27 10:19 ` Michael Ellerman
2016-01-27 10:44 ` Torsten Duwe
2016-01-28 4:26 ` Michael Ellerman
2016-01-28 11:50 ` Torsten Duwe
2016-01-27 12:58 ` Alan Modra
2016-01-27 13:45 ` Torsten Duwe
2016-01-28 3:39 ` Michael Ellerman
2016-02-03 7:23 ` AKASHI Takahiro
2016-02-03 8:55 ` Jiri Kosina
2016-02-03 11:24 ` Torsten Duwe
2016-02-04 9:31 ` AKASHI Takahiro
2016-02-04 11:02 ` Petr Mladek
2016-02-05 4:40 ` Balbir Singh
2016-02-05 10:22 ` Petr Mladek
2016-02-04 21:47 ` Jiri Kosina
2016-01-25 15:27 ` [PATCH v6 2/9] ppc64le FTRACE_WITH_REGS implementation Torsten Duwe
2016-01-25 15:29 ` [PATCH v6 3/9] ppc use ftrace_modify_all_code default Torsten Duwe
2016-01-25 15:29 ` [PATCH v6 4/9] ppc64 ftrace_with_regs configuration variables Torsten Duwe
2016-01-25 15:30 ` [PATCH v6 5/9] ppc64 ftrace_with_regs: spare early boot and low level Torsten Duwe
2016-01-25 15:31 ` [PATCH v6 6/9] ppc64 ftrace: disable profiling for some functions Torsten Duwe
2016-01-25 15:31 ` [PATCH v6 7/9] ppc64 ftrace: disable profiling for some files Torsten Duwe
2016-01-25 15:33 ` [PATCH v6 8/9] Implement kernel live patching for ppc64le (ABIv2) Torsten Duwe
2016-01-26 10:50 ` Miroslav Benes [this message]
2016-01-26 12:48 ` Petr Mladek
2016-01-26 13:56 ` Torsten Duwe
2016-02-02 12:12 ` Petr Mladek
2016-02-02 15:45 ` Torsten Duwe
2016-02-02 16:47 ` Petr Mladek
2016-02-02 20:39 ` Jiri Kosina
2016-01-26 14:00 ` Torsten Duwe
2016-01-26 14:14 ` Miroslav Benes
2016-01-27 1:53 ` Jessica Yu
2016-02-02 13:46 ` [PATCH v6 8/9] " Denis Kirjanov
2016-02-10 18:03 ` Torsten Duwe
2016-01-25 15:33 ` [PATCH v6 9/9] Enable LIVEPATCH to be configured on ppc64le and add livepatch.o if it is selected Torsten Duwe
2016-01-27 10:51 ` [PATCH v6 0/9] ftrace with regs + live patching for ppc64 LE (ABI v2) Balbir Singh
2016-01-27 12:19 ` Torsten Duwe
2016-01-28 2:41 ` Balbir Singh
2016-01-28 3:31 ` Michael Ellerman
2016-01-28 11:19 ` Torsten Duwe
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