TODO

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m (PA-RISC Linux TODO (actually this is Helge's TODO list))
m (PA-RISC Linux TODO (actually this is Helge's TODO list))
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= PA-RISC Linux TODO (actually this is Helge's TODO list) =
 
= PA-RISC Linux TODO (actually this is Helge's TODO list) =
  
== Status & TODO 2016-11-25 ==
+
== Status & TODO 2016-11-28 ==
  
 
* Enable UBSAN and fix allouts
 
* Enable UBSAN and fix allouts
 +
* implement libnuma kernel support to report on C8000 one socket with 2 cores.
 
* STARTED: Add KASLR (Kernel Address Layout Randomization, ARCH_HAS_ELF_RANDOMIZE, arch_mmap_rnd() and such) - https://patchwork.kernel.org/patch/9377963/
 
* STARTED: Add KASLR (Kernel Address Layout Randomization, ARCH_HAS_ELF_RANDOMIZE, arch_mmap_rnd() and such) - https://patchwork.kernel.org/patch/9377963/
 +
** Fix kernel to load -fpie compiled programs not at 0x400000
 +
* STARTED: detect physically broken memory - utilize PDT (http://ftp.parisc-linux.org/docs/arch/pdc20-v1.1-Ch4-pdc.pdf (page #46)) - https://patchwork.kernel.org/patch/2541561/,  new idea: use: PDC_PAT_MEM_PD_INFO (see pdcpat.h)
 +
* STARTED: Implement GENERIC_CLOCKEVENTS with cr16 cycle counter ? (kernel 4.9)
 +
* debian parisc perl bug (http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=721537) shows that mmap on parisc linux is horribly inefficient.  We allocate huge maps for small files. This should be improved. Mailthread: " parisc mmap: private file maps" ,http://www.spinics.net/lists/linux-parisc/msg05083.html  or  https://rt.perl.org/Public/Bug/Display.html?id=119567  https://rt.perl.org/Public/Bug/Display.html?id=119567
 
* Why does CONFIG_DEBUG_TIMEKEEPING=y does not work? -> maybe: http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=604a830d4fb5bf2334263bd597de22652e63b7e6* Add kasan checks ?
 
* Why does CONFIG_DEBUG_TIMEKEEPING=y does not work? -> maybe: http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=604a830d4fb5bf2334263bd597de22652e63b7e6* Add kasan checks ?
* Circular dependency problems with kde packages caused by vlc and ffmpeg (Dave)
 
* Find reproducer for gcc bug in espresso: https://buildd.debian.org/status/fetch.php?pkg=espresso&arch=hppa&ver=5.4.0%2Bdfsg-5&stamp=1474830912
 
 
* unaligned warning (from glibc) when running apt-get: https://sourceware.org/bugzilla/show_bug.cgi?id=20243
 
* unaligned warning (from glibc) when running apt-get: https://sourceware.org/bugzilla/show_bug.cgi?id=20243
 
* rebuild packages with kernel 4.7 which has better timing: ismrmrd, haskell-http-conduit, ...  
 
* rebuild packages with kernel 4.7 which has better timing: ismrmrd, haskell-http-conduit, ...  
* Implement GENERIC_CLOCKEVENTS with cr16 cycle counter ? (kernel 4.9)
 
 
* Remove TIF_RESTORE_SIGMASK define -> https://patchwork.kernel.org/patch/9230443/, "virtually mapped stacks and thread_info cleanup" -> https://lwn.net/Articles/693026/
 
* Remove TIF_RESTORE_SIGMASK define -> https://patchwork.kernel.org/patch/9230443/, "virtually mapped stacks and thread_info cleanup" -> https://lwn.net/Articles/693026/
 
* add wiki page about kernel cross-compiling
 
* add wiki page about kernel cross-compiling
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** Implement kernel VDSO support
 
** Implement kernel VDSO support
 
** convert irq handling to use CONFIG_IRQ_DOMAIN_HIERARCHY (serial port problem, action handler msising when registering irq)
 
** convert irq handling to use CONFIG_IRQ_DOMAIN_HIERARCHY (serial port problem, action handler msising when registering irq)
 +
** Circular dependency problems with kde packages caused by vlc and ffmpeg (Dave)
 
** Due to very bad performance running multiple copies of dot program (Dave)
 
** Due to very bad performance running multiple copies of dot program (Dave)
 
*** In vtk6 debian package, adding DOT_NUM_THREADS = 1 helps.
 
*** In vtk6 debian package, adding DOT_NUM_THREADS = 1 helps.
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** modprobe ipmi_si loads the BMC driver, but it could be loaded automatically too..How to get CPU temp? (ipmi-chassis --get-chassis-status crashes the machine).
 
** modprobe ipmi_si loads the BMC driver, but it could be loaded automatically too..How to get CPU temp? (ipmi-chassis --get-chassis-status crashes the machine).
 
** 3.14 partly: return ((unsigned long) mapping >> 7) & ((SHMLBA >> PAGE_SHIFT) - 1); in arch/parisc/kernel/sys_parisc.c
 
** 3.14 partly: return ((unsigned long) mapping >> 7) & ((SHMLBA >> PAGE_SHIFT) - 1); in arch/parisc/kernel/sys_parisc.c
** 3.14 partly: debian parisc perl bug (http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=721537) shows that mmap on parisc linux is horribly inefficient.  We allocate huge maps for small files. This should be improved. Mailthread: " parisc mmap: private file maps" ,http://www.spinics.net/lists/linux-parisc/msg05083.html  or  https://rt.perl.org/Public/Bug/Display.html?id=119567  https://rt.perl.org/Public/Bug/Display.html?id=119567
 
 
** implement .con_font_set (consw) in sticon.c (to be able to change fonts at runtime)
 
** implement .con_font_set (consw) in sticon.c (to be able to change fonts at runtime)
 
** why does mc hangs when exiting on sticon ?
 
** why does mc hangs when exiting on sticon ?
 
** better implementation to get stack pointer (in return_address(), in stack checker in irq.c, ...)
 
** better implementation to get stack pointer (in return_address(), in stack checker in irq.c, ...)
** detect physically broken memory - utilize PDT (http://ftp.parisc-linux.org/docs/arch/pdc20-v1.1-Ch4-pdc.pdf (page #46)) - https://patchwork.kernel.org/patch/2541561/,  new idea: use: PDC_PAT_MEM_PD_INFO (see pdcpat.h)
 
  
 
* Kernel: Hard to solve outstanding issues
 
* Kernel: Hard to solve outstanding issues
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* Kernel: still missing Linux kernel development (no patches available yet):
 
* Kernel: still missing Linux kernel development (no patches available yet):
** Fix kernel to load -fpie compiled programs not at 0x400000
 
 
** maybe implement transparent huge pages (due to cache coherency technically only possible on PA8500-PA8700 CPUs, not possible on PA8800-PA8900 CPUs)
 
** maybe implement transparent huge pages (due to cache coherency technically only possible on PA8500-PA8700 CPUs, not possible on PA8800-PA8900 CPUs)
 
** optimize flush_dcache_page() implementation like sparc. See Documentation/cachetlb.txt, e.g. used in aio subsystem
 
** optimize flush_dcache_page() implementation like sparc. See Documentation/cachetlb.txt, e.g. used in aio subsystem
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** use pdc_add_valid() in kern_addr_valid(),  protect against crashable acesses (like for superio-pc-drivers-detection in lp), add pdc_add_valid() to create a probe_kernel_read() implementation.
 
** use pdc_add_valid() in kern_addr_valid(),  protect against crashable acesses (like for superio-pc-drivers-detection in lp), add pdc_add_valid() to create a probe_kernel_read() implementation.
 
** arch/parisc/kernel/sys_parisc.c -> use SYSCALL_ALIAS() -> maybe
 
** arch/parisc/kernel/sys_parisc.c -> use SYSCALL_ALIAS() -> maybe
** implement libnuma kernel support to report on C8000 one socket with 2 cores.
 
 
** Review gettimeofday and clock_gettime() implementation, possibly use a light-weight-syscall and rely on cr16 and cpu speed for more accurate timing? similiar to commit http://git.kernel.org/cgit/linux/kernel/git/stable/linux-stable.git/commit/?id=18ad51dd342a7eb09dbcd059d0b451b616d4dafc  
 
** Review gettimeofday and clock_gettime() implementation, possibly use a light-weight-syscall and rely on cr16 and cpu speed for more accurate timing? similiar to commit http://git.kernel.org/cgit/linux/kernel/git/stable/linux-stable.git/commit/?id=18ad51dd342a7eb09dbcd059d0b451b616d4dafc  
  
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* Debian packages / Userspace work
 
* Debian packages / Userspace work
 
** IMPORTANT: fix OpenJDK - fixes required in zeroport (stack grows up!).
 
** IMPORTANT: fix OpenJDK - fixes required in zeroport (stack grows up!).
** Fix qemu
+
** Fix qemu -> Richard Henderson started userspace-qemu in 11/2016: git://github.com/rth7680/qemu.git tgt-hppa
 
** 64-bit userspace, 64-bit binutils needs to be fixed to get multiple stub section support.
 
** 64-bit userspace, 64-bit binutils needs to be fixed to get multiple stub section support.
 
** gcc -> join 32- and 64bit compiler, make "-m64" work, get rid of hppa64-linux-gnu-gcc
 
** gcc -> join 32- and 64bit compiler, make "-m64" work, get rid of hppa64-linux-gnu-gcc

Revision as of 13:10, 28 November 2016

Contents

PA-RISC Linux TODO (actually this is Helge's TODO list)

Status & TODO 2016-11-28

  • Kernel: still missing Linux kernel development (no patches available yet):
    • maybe implement transparent huge pages (due to cache coherency technically only possible on PA8500-PA8700 CPUs, not possible on PA8800-PA8900 CPUs)
    • optimize flush_dcache_page() implementation like sparc. See Documentation/cachetlb.txt, e.g. used in aio subsystem
    • fix wrong _init notation in kernel
    • NO_IRQ -> should be converted to (0) instead of (-1) -> Helge (check assembly, check in drivers/parisc/*)
    • implement alternative coding for UP/SMP. See arch/x86/include/asm/alternative.h
    • check assembly in drivers/parisc/*
    • use pdc_add_valid() in kern_addr_valid(), protect against crashable acesses (like for superio-pc-drivers-detection in lp), add pdc_add_valid() to create a probe_kernel_read() implementation.
    • arch/parisc/kernel/sys_parisc.c -> use SYSCALL_ALIAS() -> maybe
    • Review gettimeofday and clock_gettime() implementation, possibly use a light-weight-syscall and rely on cr16 and cpu speed for more accurate timing? similiar to commit http://git.kernel.org/cgit/linux/kernel/git/stable/linux-stable.git/commit/?id=18ad51dd342a7eb09dbcd059d0b451b616d4dafc
  • Kernel: Low priority patches needs further work
    • disable FP-register save/restore at kernel entry? - https://patchwork.kernel.org/patch/3975291/
    • enable 16k/64k kernel page sizes (still cacheflushing-issues with SCSI driver, additional work in glibc needed to deal with >4k page size, e.g. ld-loader alignments of data/code segments)
    • Superdome support - can someone test? Should work better now with latest kernels.
    • Visualize FX support (will probably never happen!)
    • implement BUG() and WARN() with inline assembly so that interrupt happens in delay branch of "or,<> %r0,cond,%r0". Probably not possible, because gcc will report "control reaches end of non-void function" warnings/errors.
  • Debian packages / Userspace work
    • IMPORTANT: fix OpenJDK - fixes required in zeroport (stack grows up!).
    • Fix qemu -> Richard Henderson started userspace-qemu in 11/2016: git://github.com/rth7680/qemu.git tgt-hppa
    • 64-bit userspace, 64-bit binutils needs to be fixed to get multiple stub section support.
    • gcc -> join 32- and 64bit compiler, make "-m64" work, get rid of hppa64-linux-gnu-gcc
  • userspace
  • palo (PA-RISC Boot Loader):
    • Modify (if possible), that palo can read (sequential) tftpbootable-vmlinuxes as well as the current boot-vmlinux images (simplifies build/handling)
    • move decompression of Kernel to Linux kernel code instead of palo

Upstream PA-RISC-related kernel patch history

Debian kernel and userspace programs

Debian kernel / Generic Kernel bugs fixed

    • DONE: Fixed 64bit SMP kernel & sticon on machines with more than 4GB RAM (Kernel 3.12)
    • DONE: Lots of syscall fixes regarding compat kernel
    • DONE: send patches to remove UP from debian kernels, use sil680 instead of siimage, see http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=721191 -> fixed in 3.12 / 3.13
    • DONE: Enable BMC in c8000 default kernel config - ipmi driver (CONFIG_IPMI_HANDLER=y) - http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=747482
    • DONE: remove HIL RTC from debian kernel - it creates a backtrace at boot because we have already another rtc0 active.
    • DONE: add ppdev driver, needed by CUPS, systemd reports missing module load (3.17 & 3.16 kernel)
    • DONE: Add crc-modules, event, isofs, jfs, mouse, sata, sound, squashfs, udf, uinput, scsi-common, scsi-extra, loop, serial and usb-serial debian-installer packages
    • DONE: Kernel build problem: a) disable -mfast-indirect-calls in Makefile, b) gcc compiler bug in > gcc-4.8.3-3
    • DONE: Drop HPUX-support from kernel (Kernel 4.0)
    • DONE: implemented HUGE pages
    • DONE: kernel timerfd_settime/timerfd_gettime issue, test with debian package: liblinux-fd-perl -> https://patchwork.kernel.org/patch/7951661/, backported to all kernels
    • DONE: kernel ptrace bug: http://thread.gmane.org/gmane.linux.ports.parisc/26273, possible fix: https://patchwork.kernel.org/patch/8063301/
    • DONE: Implement CONFIG_DEBUG_STACK_USAGE, in kernel 4.6
    • DONE: Use 32bit exception table entries, in kernel 4.6
    • DONE: implemented seccomp syscal, including SECCOMP_MODE_STRICT and mode 2
    • DONE: Fixed FTRACE support (http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=366dd4ea9d5f0eb78fdf4982d76506f99480ec0a)
    • DONE: Add syscall ftrace support
    • DONE: Simplify get_user()/put_user() with regard to %sr0/%sr2 usage.
    • DONE: Add tracehook support (needed for seccomp testcases, gdb, ...)

ABI breakages (HP-UX support)

Considerations between Debian unstable and Debian Jessie release

Jessie was not stable on SMP machines, particularly those with PA8800/PA8900 processors. It's recommended to use kernel 4.4.15 or later. The current default gcc for unstable is gcc 5.4. Most hppa fixes have been back ported to 4.9 but not all. It shouldn't hurt to use binutils from unstable. Debian glibc 2.23 is best. Most old packages should still work although there maybe inequivalent aliasing issues which are relevant on PA8800. There's also a nasty issue with gmon_start being in every shared library in Jessie. This caused a few headaches and potentially breaks applications when it's removed from a library. If you stick with the glibc in Jessie, multithreaded applications may not work as well as they could, but maybe that's not important. The kernel update is the most important one. Since hppa moved to ports, there has been a huge number of bug fixes. System stability is dramatically improved and I believe more packages are available than ever before. It's better to run unstable and just be selective about running "apt-get upgrade". (by Dave Anglin)

parisc-linux.org Homepage and Debian build server infrastructure work

Testsuites, kernel and userspace testing tools

TODO Drivers

  • IPMI support on rp-class / Support graceful shutdown from BMC on rp servers (`PC -GRACEFUL`)
  • write Lasi floppy driver
  • write Suckyio floppy driver
  • write spifi driver (rbrad)
  • modify ncr53c8xx driver for Outfield (735 & 755)
  • write GSC FDDI driver
  • write Timi ASIC (74x) support
  • EISA DMA support

Review all the todo entries below!

  • ns87415 dma doesn't work reliably on suckyio-systems
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