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* parisc: fix kernel memory layout in vmlinux.ld.SHelge Deller2013-11-301-4/+2
| | | | | | | | | | | | | | | | | When building a 64bit kernel sometimes functions in the .init section were not able to reach the standard kernel function. Main reason for this problem is, that the linkage tables (.plt, .opd, .dlt) tend to become pretty huge and thus the distance gets too big for short calls. One option to avoid this is to use the -mlong-calls compiler option, but this increases the binary size and introduces a performance penalty. Instead, with this patch we just lay out the binary differently. Init code is stored first, followed by text, R/O and finally R/W data. This means, that init and text code is now much closer to each other, which is sufficient to reach each other by short calls. Signed-off-by: Helge Deller <deller@gmx.de>
* parisc: Do not crash 64bit SMP kernels on machines with >= 4GB RAMHelge Deller2013-10-271-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since the beginning of the parisc-linux port, sometimes 64bit SMP kernels were not able to bring up other CPUs than the monarch CPU and instead crashed the kernel. The reason was unclear, esp. since it involved various machines (e.g. J5600, J6750 and SuperDome). Testing showed, that those crashes didn't happened when less than 4GB were installed, or if a 32bit Linux kernel was booted. In the end, the fix for those SMP problems is trivial: During the early phase of the initialization of the CPUs, including the monarch CPU, the PDC_PSW firmware function to enable WIDE (=64bit) mode is called. It's documented that this firmware function may clobber various registers, and one one of those possibly clobbered registers is %cr30 which holds the task thread info pointer. Now, if %cr30 would always have been clobbered, then this bug would have been detected much earlier. But lots of testing finally showed, that - at least for %cr30 - on some machines only the upper 32bits of the 64bit register suddenly turned zero after the firmware call. So, after finding the root cause, the explanation for the various crashes became clear: - On 32bit SMP Linux kernels all upper 32bit were zero, so we didn't faced this problem. - Monarch CPUs in 64bit mode always booted sucessfully, because the inital task thread info pointer was below 4GB. - Secondary CPUs booted sucessfully on machines with less than 4GB RAM because the upper 32bit were zero anyay. - Secondary CPus failed to boot if we had more than 4GB RAM and the task thread info pointer was located above the 4GB boundary. Finally, the patch to fix this problem is trivial by saving the %cr30 register before the firmware call and restoring it afterwards. Signed-off-by: Helge Deller <deller@gmx.de> Signed-off-by: John David Anglin <dave.anglin@bell.net> Cc: <stable@vger.kernel.org> # 2.6.12+ Signed-off-by: Helge Deller <deller@gmx.de>
* [PARISC] only make executable areas executableJames Bottomley2011-04-151-2/+3
| | | | | | | | | | | | | | | | | | Currently parisc has the whole kernel marked as RWX, meaning any kernel page at all is eligible to be executed. This can cause a theoretical problem on systems with combined I/D TLB because the act of referencing a page causes a TLB insertion with an executable bit. This TLB entry may be used by the CPU as the basis for speculating the page into the I-Cache. If this speculated page is subsequently used for a user process, there is the possibility we will get a stale I-cache line picked up as the binary executes. As a point of good practise, only mark actual kernel text pages as executable. The same has to be done for init_text pages, but they're converted to data pages (and the I-Cache flushed) when the init memory is released. Signed-off-by: James Bottomley <James.Bottomley@suse.de>
* Fix common misspellingsLucas De Marchi2011-03-311-1/+1
| | | | | | Fixes generated by 'codespell' and manually reviewed. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
* Rename .data.read_mostly to .data..read_mostly.Denys Vlasenko2010-03-031-1/+1
| | | | | Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Signed-off-by: Michal Marek <mmarek@suse.cz>
* parisc: hijack jump to start_kernelKyle McMartin2008-10-101-1/+1
| | | | | | | | | | | | Bang in our own start_parisc call, which initializes the PDC width, and turns on the FPU. Previously, if CONFIG_PRINTK_TIME was on, we'd attempt to use the FPU before we had enabled it, resulting in a difficult to diagnose panic. This patch causes init_per_cpu to redundantly set these for cpu0, but this is harmless.
* parisc: move head.S to head.text sectionKyle McMartin2008-06-131-1/+2
| | | | | | And explicitly list it in vmlinux.lds... Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
* Revert "parisc: fix trivial section name warnings"Kyle McMartin2008-06-131-1/+1
| | | | | | This reverts commit bd3bb8c15b9a80dbddfb7905b237a4a11a4725b4. Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
* parisc: fix trivial section name warningsHelge Deller2008-05-151-1/+1
| | | | | | | | | | | | This trivial patch fixes the following section warnings on PARISC: > WARNING: vmlinux.o (.text.1): unexpected section name. >The (.[number]+) following section name are ld generated and not expected. > Did you forget to use "ax"/"aw" in a .S file? > Note that for example <linux/init.h> contains > section definitions for use in .S files. Signed-off-by: Helge Deller <deller@gmx.de> Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
* [PARISC] head.S: section mismatch fixesHelge Deller2008-03-151-3/+4
| | | | | | | | | | | - move boot_args[] into the init section - move $global$ into the read_mostly section - fix the following two section mismatches: WARNING: vmlinux.o(.text+0x9c): Section mismatch: reference to .init.text:start_kernel (between '$pgt_fill_loop' and '$is_pa20') WARNING: vmlinux.o(.text+0xa0): Section mismatch: reference to .init.text:start_kernel (between '$pgt_fill_loop' and '$is_pa20') Signed-off-by: Helge Deller <deller@gmx.de> SIgned-off-by: Kyle McMartin <kyle@mcmartin.ca>
* [PARISC] Kill off broken irqstack codeKyle McMartin2007-10-181-4/+0
| | | | | | | It's been unfinished and broken long enough, and I have some ideas on how to do it more cleanly. Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
* [PARISC] Kill off the last vestiges of ASM_PAGE_SIZEKyle McMartin2007-10-181-1/+1
| | | | | | Sam's previous patch missed a few uses of ASM_PAGE_SIZE. Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
* [PARISC] more ENTRY(), ENDPROC(), END() conversionsHelge Deller2007-02-171-6/+9
| | | | | Signed-off-by: Helge Deller <deller@gmx.de> Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
* Remove all inclusions of <linux/config.h>Dave Jones2006-10-041-2/+0
| | | | | | kbuild explicitly includes this at build time. Signed-off-by: Dave Jones <davej@redhat.com>
* [PARISC] Further work for multiple page sizesHelge Deller2006-04-211-7/+8
| | | | | | | | | | More work towards supporing multiple page sizes on 64-bit. Convert some assumptions that 64bit uses 3 level page tables into testing PT_NLEVELS. Also some BUG() to BUG_ON() conversions and some cleanups to assembler. Signed-off-by: Helge Deller <deller@parisc-linux.org> Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
* [PARISC] Replace uses of __LP64__ with CONFIG_64BITGrant Grundler2005-10-211-13/+13
| | | | | | | | 2.6.12-rc4-pa3 s/__LP64__/CONFIG_64BIT/ and fixup config.h usage Signed-off-by: Grant Grundler <grundler@parisc-linux.org> Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
* [PARISC] Make sure use of RFI conforms to PA 2.0 and 1.1 arch docsGrant Grundler2005-10-211-38/+9
| | | | | | | | | | | | | | | 2.6.12-rc4-pa3 : first pass at making sure use of RFI conforms to PA 2.0 arch pages F-4 and F-5, PA 1.1 Arch page 3-19 and 3-20. The discussion revolves around all the rules for clearing PSW Q-bit. The hard part is meeting all the rules for "relied upon translation". .align directive is used to guarantee the critical sequence ends more than 8 instructions (32 bytes) from the end of page. Signed-off-by: Grant Grundler <grundler@parisc-linux.org> Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
* kbuild: m68k,parisc,ppc,ppc64,s390,xtensa use generic asm-offsets.h supportSam Ravnborg2005-09-091-1/+1
| | | | | | Delete obsoleted parts form arch makefiles and rename to asm-offsets.h Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
* Linux-2.6.12-rc2v2.6.12-rc2Linus Torvalds2005-04-161-0/+386
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
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