From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Fri, 7 May 2010 15:46:50 +1000 From: Paul Mackerras To: linuxppc-dev@ozlabs.org Subject: [PATCH] powerpc: Avoid bad relocations in iSeries code Message-ID: <20100507054650.GC25173@drongo> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Subrata Modak List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , 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 Signed-off-by: Paul Mackerras --- 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 */