* Re: [PATCH] x86: livepatch: Treat R_X86_64_PLT32 as R_X86_64_PC32
@ 2019-02-19 8:16 chenzefeng (A)
0 siblings, 0 replies; 5+ messages in thread
From: chenzefeng (A) @ 2019-02-19 8:16 UTC (permalink / raw)
To: Petr Mladek, chengjian (D)
Cc: stable, Jiri Kosina, hjl.tools, jpoimboe, sjenning, vojtech,
tglx, mingo, hpa, gregkh, x86, live-patching, linux-kernel,
Xiexiuqi
Hi,
I am sorry this email was sent by accident. Please ignore this email.
Best Regards
-----邮件原件-----
发件人: chenzefeng (A)
发送时间: 2019年2月19日 14:38
收件人: 'Petr Mladek' <pmladek@suse.com>; chengjian (D) <cj.chengjian@huawei.com>
抄送: 'stable@vger.kernel.org' <stable@vger.kernel.org>; Jiri Kosina <jikos@kernel.org>; hjl.tools@gmail.com; jpoimboe@redhat.com; sjenning@redhat.com; vojtech@suse.com; tglx@linutronix.de; mingo@redhat.com; hpa@zytor.com; gregkh@linuxfoundation.org; x86@kernel.org; live-patching@vger.kernel.org; linux-kernel@vger.kernel.org; Xiexiuqi <xiexiuqi@huawei.com>
主题: Re:[PATCH] x86: livepatch: Treat R_X86_64_PLT32 as R_X86_64_PC32
On Mon 2019-02-18 17:22, Petr wrote:
> On Mon 2019-02-18 13:29:11, chengjian (D) wrote:
> > Hi,Jiri
> >
> >
> > This patch should be merged into 4.4 stable,
> >
> > which still use klp_write_module_reloc.
> >
> >
> > https://elixir.bootlin.com/linux/v4.4.174/source/arch/x86/kernel/livep
> > atch.c
> >
> >
> > ZeFeng may have sent a stable(4.4-y) patch to the wrong mail-list(mainline).
>
> ZeFeng or Chengjian, please, send the patch once again with stable@vger.kernel.org in CC and explanation that it is needed only for 4.4 and why.
>
> This thread is already too long and messed to be proceed by stable people effectively.
>
> Best Regards,
> Petr
On x86-64, for 32-bit PC-relacive branches, we can generate PLT32 relocation, instead of PC32 relocation. and R_X86_64_PLT32 can be treated the same as R_X86_64_PC32 since linux kernel doesn't use PLT.
commit b21ebf2fb4cd ("x86: Treat R_X86_64_PLT32 as R_X86_64_PC32") been fixed for the module loading, but not fixed for livepatch relocation, which will fail to load livepatch with the error message as follow:
relocation failed for symbol <symbol name> at <symbol address>
This issue only effacted the kernel version from 4.0 to 4.6, becauce the function klp_write_module_reloc is introduced by:
commit b700e7f03df5 ("livepatch: kernel: add support for live patching") and deleted by: commit 425595a7fc20
("livepatch: reuse module loader code to write relocations")
Signed-off-by: chenzefeng <chenzefeng2@huawei.com>
---
arch/x86/kernel/livepatch.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/arch/x86/kernel/livepatch.c b/arch/x86/kernel/livepatch.c index d1d35cc..579f8f8 100644
--- a/arch/x86/kernel/livepatch.c
+++ b/arch/x86/kernel/livepatch.c
@@ -58,6 +58,7 @@ int klp_write_module_reloc(struct module *mod, unsigned long type,
val = (s32)value;
break;
case R_X86_64_PC32:
+ case R_X86_64_PLT32:
val = (u32)(value - loc);
break;
default:
--
1.8.5.6
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] x86: livepatch: Treat R_X86_64_PLT32 as R_X86_64_PC32
2019-02-20 12:37 chenzefeng (A)
2019-02-21 8:42 ` Petr Mladek
@ 2019-02-21 11:47 ` gregkh
1 sibling, 0 replies; 5+ messages in thread
From: gregkh @ 2019-02-21 11:47 UTC (permalink / raw)
To: chenzefeng (A); +Cc: stable, Petr Mladek, Jiri Kosina, hjl.tools, chengjian (D)
On Wed, Feb 20, 2019 at 12:37:54PM +0000, chenzefeng (A) wrote:
> On x86-64, for 32-bit PC-relacive branches, we can generate PLT32 relocation, instead of PC32 relocation. and R_X86_64_PLT32 can be treated the same as R_X86_64_PC32 since linux kernel doesn't use PLT.
>
> commit b21ebf2fb4cd ("x86: Treat R_X86_64_PLT32 as R_X86_64_PC32") been fixed for the module loading, but not fixed for livepatch relocation, which will fail to load livepatch with the error message as follow:
> relocation failed for symbol <symbol name> at <symbol address>
>
> This issue only effacted the kernel version from 4.0 to 4.6, becauce the function klp_write_module_reloc is introduced by:
> commit b700e7f03df5 ("livepatch: kernel: add support for live patching") and deleted by: commit 425595a7fc20
> ("livepatch: reuse module loader code to write relocations")
>
> Signed-off-by: chenzefeng <chenzefeng2@huawei.com>
> Reviewed-by: Petr Mladek <pmladek@suse.com>
> ---
> arch/x86/kernel/livepatch.c | 1 +
> 1 file changed, 1 insertion(+)
Now queued up, thanks.
Also, next time please wrap your changelog text at 72 columns :)
greg k-h
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] x86: livepatch: Treat R_X86_64_PLT32 as R_X86_64_PC32
2019-02-20 12:37 chenzefeng (A)
@ 2019-02-21 8:42 ` Petr Mladek
2019-02-21 11:47 ` gregkh
1 sibling, 0 replies; 5+ messages in thread
From: Petr Mladek @ 2019-02-21 8:42 UTC (permalink / raw)
To: chenzefeng (A); +Cc: gregkh, stable, Jiri Kosina, hjl.tools, chengjian (D)
On Wed 2019-02-20 12:37:54, chenzefeng (A) wrote:
> On x86-64, for 32-bit PC-relacive branches, we can generate PLT32 relocation, instead of PC32 relocation. and R_X86_64_PLT32 can be treated the same as R_X86_64_PC32 since linux kernel doesn't use PLT.
>
> commit b21ebf2fb4cd ("x86: Treat R_X86_64_PLT32 as R_X86_64_PC32") been fixed for the module loading, but not fixed for livepatch relocation, which will fail to load livepatch with the error message as follow:
> relocation failed for symbol <symbol name> at <symbol address>
>
> This issue only effacted the kernel version from 4.0 to 4.6, becauce the function klp_write_module_reloc is introduced by:
> commit b700e7f03df5 ("livepatch: kernel: add support for live patching") and deleted by: commit 425595a7fc20
> ("livepatch: reuse module loader code to write relocations")
>
> Signed-off-by: chenzefeng <chenzefeng2@huawei.com>
The patch looks fine for the 4.4 stable kernel:
Reviewed-by: Petr Mladek <pmladek@suse.com>
Best Regards,
Petr
^ permalink raw reply [flat|nested] 5+ messages in thread
* [PATCH] x86: livepatch: Treat R_X86_64_PLT32 as R_X86_64_PC32
@ 2019-02-20 12:37 chenzefeng (A)
2019-02-21 8:42 ` Petr Mladek
2019-02-21 11:47 ` gregkh
0 siblings, 2 replies; 5+ messages in thread
From: chenzefeng (A) @ 2019-02-20 12:37 UTC (permalink / raw)
To: gregkh; +Cc: stable, Petr Mladek, Jiri Kosina, hjl.tools, chengjian (D)
On x86-64, for 32-bit PC-relacive branches, we can generate PLT32 relocation, instead of PC32 relocation. and R_X86_64_PLT32 can be treated the same as R_X86_64_PC32 since linux kernel doesn't use PLT.
commit b21ebf2fb4cd ("x86: Treat R_X86_64_PLT32 as R_X86_64_PC32") been fixed for the module loading, but not fixed for livepatch relocation, which will fail to load livepatch with the error message as follow:
relocation failed for symbol <symbol name> at <symbol address>
This issue only effacted the kernel version from 4.0 to 4.6, becauce the function klp_write_module_reloc is introduced by:
commit b700e7f03df5 ("livepatch: kernel: add support for live patching") and deleted by: commit 425595a7fc20
("livepatch: reuse module loader code to write relocations")
Signed-off-by: chenzefeng <chenzefeng2@huawei.com>
---
arch/x86/kernel/livepatch.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/arch/x86/kernel/livepatch.c b/arch/x86/kernel/livepatch.c index d1d35cc..579f8f8 100644
--- a/arch/x86/kernel/livepatch.c
+++ b/arch/x86/kernel/livepatch.c
@@ -58,6 +58,7 @@ int klp_write_module_reloc(struct module *mod, unsigned long type,
val = (s32)value;
break;
case R_X86_64_PC32:
+ case R_X86_64_PLT32:
val = (u32)(value - loc);
break;
default:
--
1.8.5.6
^ permalink raw reply [flat|nested] 5+ messages in thread
* [PATCH] x86: livepatch: Treat R_X86_64_PLT32 as R_X86_64_PC32
@ 2019-02-19 8:20 chenzefeng (A)
0 siblings, 0 replies; 5+ messages in thread
From: chenzefeng (A) @ 2019-02-19 8:20 UTC (permalink / raw)
To: stable
On x86-64, for 32-bit PC-relacive branches, we can generate PLT32 relocation, instead of PC32 relocation. and R_X86_64_PLT32 can be treated the same as R_X86_64_PC32 since linux kernel doesn't use PLT.
commit b21ebf2fb4cd ("x86: Treat R_X86_64_PLT32 as R_X86_64_PC32") been fixed for the module loading, but not fixed for livepatch relocation, which will fail to load livepatch with the error message as follow:
relocation failed for symbol <symbol name> at <symbol address>
This issue only effacted the kernel version from 4.0 to 4.6, becauce the function klp_write_module_reloc is introduced by:
commit b700e7f03df5 ("livepatch: kernel: add support for live patching") and deleted by: commit 425595a7fc20
("livepatch: reuse module loader code to write relocations")
Signed-off-by: chenzefeng <chenzefeng2@huawei.com>
---
arch/x86/kernel/livepatch.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/arch/x86/kernel/livepatch.c b/arch/x86/kernel/livepatch.c index d1d35cc..579f8f8 100644
--- a/arch/x86/kernel/livepatch.c
+++ b/arch/x86/kernel/livepatch.c
@@ -58,6 +58,7 @@ int klp_write_module_reloc(struct module *mod, unsigned long type,
val = (s32)value;
break;
case R_X86_64_PC32:
+ case R_X86_64_PLT32:
val = (u32)(value - loc);
break;
default:
--
1.8.5.6
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2019-02-21 11:47 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-02-19 8:16 [PATCH] x86: livepatch: Treat R_X86_64_PLT32 as R_X86_64_PC32 chenzefeng (A)
2019-02-19 8:20 chenzefeng (A)
2019-02-20 12:37 chenzefeng (A)
2019-02-21 8:42 ` Petr Mladek
2019-02-21 11:47 ` gregkh
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).