From: Paul Mackerras <paulus@samba.org>
To: linuxppc-dev@ozlabs.org
Cc: Subrata Modak <subrata@linux.vnet.ibm.com>
Subject: [PATCH] powerpc: Avoid bad relocations in iSeries code
Date: Fri, 7 May 2010 15:46:50 +1000 [thread overview]
Message-ID: <20100507054650.GC25173@drongo> (raw)
Subrata Modak reported that building a CONFIG_RELOCATABLE kernel with
CONFIG_ISERIES enabled gives the following warnings:
WARNING: 4 bad relocations
c00000000007216e R_PPC64_ADDR16_HIGHEST __ksymtab+0x00000000009dcec8
c000000000072172 R_PPC64_ADDR16_HIGHER __ksymtab+0x00000000009dcec8
c00000000007217a R_PPC64_ADDR16_HI __ksymtab+0x00000000009dcec8
c00000000007217e R_PPC64_ADDR16_LO __ksymtab+0x00000000009dcec8
The reason is that decrementer_iSeries_masked is using
LOAD_REG_IMMEDIATE to get the address of a kernel symbol, which
creates relocations that aren't handled by the kernel relocator code.
Instead of reading the tb_ticks_per_jiffy variable, we can just set
the decrementer to its maximum value (0x7fffffff) and that will work
just as well. In fact timer_interrupt sets the decrementer to that
value initially anyway, and we are sure to get into timer_interrupt
once interrupts are reenabled because we store 1 to the decrementer
interrupt flag in the lppaca (LPPACADECRINT(r12) here).
Reported-by: Subrata Modak <subrata@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
---
arch/powerpc/platforms/iseries/exception.S | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/powerpc/platforms/iseries/exception.S b/arch/powerpc/platforms/iseries/exception.S
index fba5bf9..32a56c6 100644
--- a/arch/powerpc/platforms/iseries/exception.S
+++ b/arch/powerpc/platforms/iseries/exception.S
@@ -252,8 +252,8 @@ decrementer_iSeries_masked:
li r11,1
ld r12,PACALPPACAPTR(r13)
stb r11,LPPACADECRINT(r12)
- LOAD_REG_IMMEDIATE(r12, tb_ticks_per_jiffy)
- lwz r12,0(r12)
+ li r12,-1
+ clrldi r12,r12,33 /* set DEC to 0x7fffffff */
mtspr SPRN_DEC,r12
/* fall through */
reply other threads:[~2010-05-07 5:46 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20100507054650.GC25173@drongo \
--to=paulus@samba.org \
--cc=linuxppc-dev@ozlabs.org \
--cc=subrata@linux.vnet.ibm.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.