From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jessica Yu Date: Thu, 06 Jun 2019 15:21:31 +0000 Subject: Re: [PATCH modules 0/2] Fix handling of exit unwinding sections (on ARM) Message-Id: <20190606152131.GB27669@linux-8ccs> List-Id: References: <20190603105726.22436-1-matthias.schiffer@ew.tq-group.com> <61f233518ba863f9d5783dd10e468ee5bf22b69a.camel@ew.tq-group.com> In-Reply-To: <61f233518ba863f9d5783dd10e468ee5bf22b69a.camel@ew.tq-group.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Matthias Schiffer Cc: Russell King , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-ia64@vger.kernel.org +++ Matthias Schiffer [06/06/19 10:14 +0200]: >On Mon, 2019-06-03 at 12:57 +0200, Matthias Schiffer wrote: >> For some time (050d18d1c651 "ARM: 8650/1: module: handle negative >> R_ARM_PREL31 addends correctly", v4.11+), building a kernel without >> CONFIG_MODULE_UNLOAD would lead to module loads failing on ARM >> systems with >> certain memory layouts, with messages like: >> >> imx_sdma: section 16 reloc 0 sym '': relocation 42 out of range >> (0x7f015260 -> 0xc0f5a5e8) >> >> (0x7f015260 is in the module load area, 0xc0f5a5e8 a regular vmalloc >> address; relocation 42 is R_ARM_PREL31) >> >> This is caused by relocatiosn in the .ARM.extab.exit.text and >> .ARM.exidx.exit.text sections referencing the .exit.text section. As >> the >> module loader will omit loading .exit.text without >> CONFIG_MODULE_UNLOAD, >> there will be relocations from loaded to unloaded sections; the >> resulting >> huge offsets trigger the sanity checks added in 050d18d1c651. >> >> IA64 might be affected by a similar issue - sections with names like >> .IA_64.unwind.exit.text and .IA_64.unwind_info.exit.text appear in >> the ld >> script - but I don't know much about that arch. >> >> Also, I'm not sure if this is stable-worthy - just enabling >> CONFIG_MODULE_UNLOAD should be a viable workaround on affected >> kernels. >> >> >> Kind regards, >> Matthias > > >Hi, >any comments on these patches? If not, who is going to take them in >their tree? I don't mind either way. I can take the patches through my tree if Russell ack's the second one (after comments have been addressed). Thanks! Jessica