1. 16 Oct, 2021 4 commits
  2. 11 Oct, 2021 1 commit
    • Marc Zyngier's avatar
      gpio: Allow per-parent interrupt data · 9658b10f
      Marc Zyngier authored and Joey Gouly's avatar Joey Gouly committed
      The core gpiolib code is able to deal with multiple interrupt parents
      for a single gpio irqchip. It however only allows a single piece
      of data to be conveyed to all flow handlers (either the gpio_chip
      or some other, driver-specific data).
      
      This means that drivers have to go through some interesting dance
      to find the correct context, something that isn't great in interrupt
      context (see aebdc8ab
      
       for a prime
      example).
      
      Instead, offer an optional way for a pinctrl/gpio driver to provide
      an array of pointers which gets used to provide the correct context
      to the flow handler.
      
      Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
      Signed-off-by: Joey Gouly's avatarJoey Gouly <joey.gouly@arm.com>
      Reviewed-by: default avatarLinus Walleij <linus.walleij@linaro.org>
      9658b10f
  3. 20 Sep, 2021 6 commits
  4. 19 Sep, 2021 18 commits
  5. 18 Sep, 2021 11 commits
    • Linus Torvalds's avatar
      alpha: move __udiv_qrnnd library function to arch/alpha/lib/ · d4d016ca
      Linus Torvalds authored
      
      
      We already had the implementation for __udiv_qrnnd (unsigned divide for
      multi-precision arithmetic) as part of the alpha math emulation code.
      
      But you can disable the math emulation code - even if you shouldn't -
      and then the MPI code that actually wants this functionality (and is
      needed by various crypto functions) will fail to build.
      
      So move the extended-precision divide code to be a regular library
      function, just like all the regular division code is.  That way ie is
      available regardless of math-emulation.
      
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      d4d016ca
    • Linus Torvalds's avatar
      alpha: mark 'Jensen' platform as no longer broken · ab41f75e
      Linus Torvalds authored
      Ok, it almost certainly is still broken on actual hardware, but the
      immediate reason for it having been marked BROKEN was a build error that
      is fixed by just making sure the low-level IO header file is included
      sufficiently early that the __EXTERN_INLINE hackery takes effect.
      
      This was marked broken back in 2017 by commit 1883c9f4
      
       ("alpha: mark
      jensen as broken"), but Ulrich Teichert made me look at it as part of my
      cross-build work to make sure -Werror actually does the right thing.
      
      There are lots of alpha configurations that do not build cleanly, but
      now it's no longer because Jensen wouldn't be buildable.  That said,
      because the Jensen platform doesn't force PCI to be enabled (Jensen only
      had EISA), it ends up being somewhat interesting as a source of odd
      configs.
      
      Reported-by: default avatarUlrich Teichert <krypton@ulrich-teichert.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      ab41f75e
    • Andrii Nakryiko's avatar
      perf bpf: Ignore deprecation warning when using libbpf's btf__get_from_id() · 219d720e
      Andrii Nakryiko authored
      
      
      Perf code re-implements libbpf's btf__load_from_kernel_by_id() API as
      a weak function, presumably to dynamically link against old version of
      libbpf shared library. Unfortunately this causes compilation warning
      when perf is compiled against libbpf v0.6+.
      
      For now, just ignore deprecation warning, but there might be a better
      solution, depending on perf's needs.
      
      Signed-off-by: default avatarAndrii Nakryiko <andrii@kernel.org>
      Cc: Alexei Starovoitov <ast@kernel.org>
      Cc: Daniel Borkmann <daniel@iogearbox.net>
      Cc: kernel-team@fb.com
      LPU-Reference: 20210914170004.4185659-1-andrii@kernel.org
      Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      219d720e
    • Ian Rogers's avatar
      libperf evsel: Make use of FD robust. · aba5daeb
      Ian Rogers authored
      
      
      FD uses xyarray__entry that may return NULL if an index is out of
      bounds. If NULL is returned then a segv happens as FD unconditionally
      dereferences the pointer. This was happening in a case of with perf
      iostat as shown below. The fix is to make FD an "int*" rather than an
      int and handle the NULL case as either invalid input or a closed fd.
      
        $ sudo gdb --args perf stat --iostat  list
        ...
        Breakpoint 1, perf_evsel__alloc_fd (evsel=0x5555560951a0, ncpus=1, nthreads=1) at evsel.c:50
        50      {
        (gdb) bt
         #0  perf_evsel__alloc_fd (evsel=0x5555560951a0, ncpus=1, nthreads=1) at evsel.c:50
         #1  0x000055555585c188 in evsel__open_cpu (evsel=0x5555560951a0, cpus=0x555556093410,
            threads=0x555556086fb0, start_cpu=0, end_cpu=1) at util/evsel.c:1792
         #2  0x000055555585cfb2 in evsel__open (evsel=0x5555560951a0, cpus=0x0, threads=0x555556086fb0)
            at util/evsel.c:2045
         #3  0x000055555585d0db in evsel__open_per_thread (evsel=0x5555560951a0, threads=0x555556086fb0)
            at util/evsel.c:2065
         #4  0x00005555558ece64 in create_perf_stat_counter (evsel=0x5555560951a0,
            config=0x555555c34700 <stat_config>, target=0x555555c2f1c0 <target>, cpu=0) at util/stat.c:590
         #5  0x000055555578e927 in __run_perf_stat (argc=1, argv=0x7fffffffe4a0, run_idx=0)
            at builtin-stat.c:833
         #6  0x000055555578f3c6 in run_perf_stat (argc=1, argv=0x7fffffffe4a0, run_idx=0)
            at builtin-stat.c:1048
         #7  0x0000555555792ee5 in cmd_stat (argc=1, argv=0x7fffffffe4a0) at builtin-stat.c:2534
         #8  0x0000555555835ed3 in run_builtin (p=0x555555c3f540 <commands+288>, argc=3,
            argv=0x7fffffffe4a0) at perf.c:313
         #9  0x0000555555836154 in handle_internal_command (argc=3, argv=0x7fffffffe4a0) at perf.c:365
         #10 0x000055555583629f in run_argv (argcp=0x7fffffffe2ec, argv=0x7fffffffe2e0) at perf.c:409
         #11 0x0000555555836692 in main (argc=3, argv=0x7fffffffe4a0) at perf.c:539
        ...
        (gdb) c
        Continuing.
        Error:
        The sys_perf_event_open() syscall returned with 22 (Invalid argument) for event (uncore_iio_0/event=0x83,umask=0x04,ch_mask=0xF,fc_mask=0x07/).
        /bin/dmesg | grep -i perf may provide additional information.
      
        Program received signal SIGSEGV, Segmentation fault.
        0x00005555559b03ea in perf_evsel__close_fd_cpu (evsel=0x5555560951a0, cpu=1) at evsel.c:166
        166                     if (FD(evsel, cpu, thread) >= 0)
      
      v3. fixes a bug in perf_evsel__run_ioctl where the sense of a branch was
          backward.
      
      Signed-off-by: default avatarIan Rogers <irogers@google.com>
      Acked-by: default avatarJiri Olsa <jolsa@redhat.com>
      Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Namhyung Kim <namhyung@kernel.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Stephane Eranian <eranian@google.com>
      Link: http://lore.kernel.org/lkml/20210918054440.2350466-1-irogers@google.com
      
      
      Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      aba5daeb
    • Michael Petlan's avatar
      perf machine: Initialize srcline string member in add_location struct · 57f0ff05
      Michael Petlan authored
      It's later supposed to be either a correct address or NULL. Without the
      initialization, it may contain an undefined value which results in the
      following segmentation fault:
      
        # perf top --sort comm -g --ignore-callees=do_idle
      
      terminates with:
      
        #0  0x00007ffff56b7685 in __strlen_avx2 () from /lib64/libc.so.6
        #1  0x00007ffff55e3802 in strdup () from /lib64/libc.so.6
        #2  0x00005555558cb139 in hist_entry__init (callchain_size=<optimized out>, sample_self=true, template=0x7fffde7fb110, he=0x7fffd801c250) at util/hist.c:489
        #3  hist_entry__new (template=template@entry=0x7fffde7fb110, sample_self=sample_self@entry=true) at util/hist.c:564
        #4  0x00005555558cb4ba in hists__findnew_entry (hists=hists@entry=0x5555561d9e38, entry=entry@entry=0x7fffde7fb110, al=al@entry=0x7fffde7fb420,
            sample_self=sample_self@entry=true) at util/hist.c:657
        #5  0x00005555558cba1b in __hists__add_entry (hists=hists@entry=0x5555561d9e38, al=0x7fffde7fb420, sym_parent=<optimized out>, bi=bi@entry=0x0, mi=mi@entry=0x0,
            sample=sample@entry=0x7fffde7fb4b0, sample_self=true, ops=0x0, block_info=0x0) at util/hist.c:288
        #6  0x00005555558cbb70 in hists__add_entry (sample_self=true, sample=0x7fffde7fb4b0, mi=0x0, bi=0x0, sym_parent=<optimized out>, al=<optimized out>, hists=0x5555561d9e38)
            at util/hist.c:1056
        #7  iter_add_single_cumulative_entry (iter=0x7fffde7fb460, al=<optimized out>) at util/hist.c:1056
        #8  0x00005555558cc8a4 in hist_entry_iter__add (iter=iter@entry=0x7fffde7fb460, al=al@entry=0x7fffde7fb420, max_stack_depth=<optimized out>, arg=arg@entry=0x7fffffff7db0)
            at util/hist.c:1231
        #9  0x00005555557cdc9a in perf_event__process_sample (machine=<optimized out>, sample=0x7fffde7fb4b0, evsel=<optimized out>, event=<optimized out>, tool=0x7fffffff7db0)
            at builtin-top.c:842
        #10 deliver_event (qe=<optimized out>, qevent=<optimized out>) at builtin-top.c:1202
        #11 0x00005555558a9318 in do_flush (show_progress=false, oe=0x7fffffff80e0) at util/ordered-events.c:244
        #12 __ordered_events__flush (oe=oe@entry=0x7fffffff80e0, how=how@entry=OE_FLUSH__TOP, timestamp=timestamp@entry=0) at util/ordered-events.c:323
        #13 0x00005555558a9789 in __ordered_events__flush (timestamp=<optimized out>, how=<optimized out>, oe=<optimized out>) at util/ordered-events.c:339
        #14 ordered_events__flush (how=OE_FLUSH__TOP, oe=0x7fffffff80e0) at util/ordered-events.c:341
        #15 ordered_events__flush (oe=oe@entry=0x7fffffff80e0, how=how@entry=OE_FLUSH__TOP) at util/ordered-events.c:339
        #16 0x00005555557cd631 in process_thread (arg=0x7fffffff7db0) at builtin-top.c:1114
        #17 0x00007ffff7bb817a in start_thread () from /lib64/libpthread.so.0
        #18 0x00007ffff5656dc3 in clone () from /lib64/libc.so.6
      
      If you look at the frame #2, the code is:
      
      488	 if (he->srcline) {
      489          he->srcline = strdup(he->srcline);
      490          if (he->srcline == NULL)
      491              goto err_rawdata;
      492	 }
      
      If he->srcline is not NULL (it is not NULL if it is uninitialized rubbish),
      it gets strdupped and strdupping a rubbish random string causes the problem.
      
      Also, if you look at the commit 1fb7d06a
      
      , it adds the srcline property
      into the struct, but not initializing it everywhere needed.
      
      Committer notes:
      
      Now I see, when using --ignore-callees=do_idle we end up here at line
      2189 in add_callchain_ip():
      
      2181         if (al.sym != NULL) {
      2182                 if (perf_hpp_list.parent && !*parent &&
      2183                     symbol__match_regex(al.sym, &parent_regex))
      2184                         *parent = al.sym;
      2185                 else if (have_ignore_callees && root_al &&
      2186                   symbol__match_regex(al.sym, &ignore_callees_regex)) {
      2187                         /* Treat this symbol as the root,
      2188                            forgetting its callees. */
      2189                         *root_al = al;
      2190                         callchain_cursor_reset(cursor);
      2191                 }
      2192         }
      
      And the al that doesn't have the ->srcline field initialized will be
      copied to the root_al, so then, back to:
      
      1211 int hist_entry_iter__add(struct hist_entry_iter *iter, struct addr_location *al,
      1212                          int max_stack_depth, void *arg)
      1213 {
      1214         int err, err2;
      1215         struct map *alm = NULL;
      1216
      1217         if (al)
      1218                 alm = map__get(al->map);
      1219
      1220         err = sample__resolve_callchain(iter->sample, &callchain_cursor, &iter->parent,
      1221                                         iter->evsel, al, max_stack_depth);
      1222         if (err) {
      1223                 map__put(alm);
      1224                 return err;
      1225         }
      1226
      1227         err = iter->ops->prepare_entry(iter, al);
      1228         if (err)
      1229                 goto out;
      1230
      1231         err = iter->ops->add_single_entry(iter, al);
      1232         if (err)
      1233                 goto out;
      1234
      
      That al at line 1221 is what hist_entry_iter__add() (called from
      sample__resolve_callchain()) saw as 'root_al', and then:
      
              iter->ops->add_single_entry(iter, al);
      
      will go on with al->srcline with a bogus value, I'll add the above
      sequence to the cset and apply, thanks!
      
      Signed-off-by: default avatarMichael Petlan <mpetlan@redhat.com>
      CC: Milian Wolff <milian.wolff@kdab.com>
      Cc: Jiri Olsa <jolsa@redhat.com>
      Fixes: 1fb7d06a
      
       ("perf report Use srcline from callchain for hist entries")
      Link: https //lore.kernel.org/r/20210719145332.29747-1-mpetlan@redhat.com
      Reported-by: default avatarJuri Lelli <jlelli@redhat.com>
      Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      57f0ff05
    • Adrian Hunter's avatar
      perf script: Fix ip display when type != attr->type · ff6f41fb
      Adrian Hunter authored
      
      
      set_print_ip_opts() was not being called when type != attr->type
      because there is not a one-to-one relationship between output types
      and attr->type. That resulted in ip not printing.
      
      The attr_type() function is removed, and the match of attr->type to
      output type is corrected.
      
      Example on ADL using taskset to select an atom cpu:
      
       # perf record -e cpu_atom/cpu-cycles/ taskset 0x1000 uname
       Linux
       [ perf record: Woken up 1 times to write data ]
       [ perf record: Captured and wrote 0.003 MB perf.data (7 samples) ]
      
       Before:
      
        # perf script | head
               taskset   428 [-01] 10394.179041:          1 cpu_atom/cpu-cycles/:
               taskset   428 [-01] 10394.179043:          1 cpu_atom/cpu-cycles/:
               taskset   428 [-01] 10394.179044:         11 cpu_atom/cpu-cycles/:
               taskset   428 [-01] 10394.179045:        407 cpu_atom/cpu-cycles/:
               taskset   428 [-01] 10394.179046:      16789 cpu_atom/cpu-cycles/:
               taskset   428 [-01] 10394.179052:     676300 cpu_atom/cpu-cycles/:
                 uname   428 [-01] 10394.179278:    4079859 cpu_atom/cpu-cycles/:
      
       After:
      
        # perf script | head
               taskset   428 10394.179041:          1 cpu_atom/cpu-cycles/:  ffffffff95a0bb97 __intel_pmu_enable_all.constprop.48+0x47 ([kernel.kallsyms])
               taskset   428 10394.179043:          1 cpu_atom/cpu-cycles/:  ffffffff95a0bb97 __intel_pmu_enable_all.constprop.48+0x47 ([kernel.kallsyms])
               taskset   428 10394.179044:         11 cpu_atom/cpu-cycles/:  ffffffff95a0bb97 __intel_pmu_enable_all.constprop.48+0x47 ([kernel.kallsyms])
               taskset   428 10394.179045:        407 cpu_atom/cpu-cycles/:  ffffffff95a0bb97 __intel_pmu_enable_all.constprop.48+0x47 ([kernel.kallsyms])
               taskset   428 10394.179046:      16789 cpu_atom/cpu-cycles/:  ffffffff95a0bb97 __intel_pmu_enable_all.constprop.48+0x47 ([kernel.kallsyms])
               taskset   428 10394.179052:     676300 cpu_atom/cpu-cycles/:      7f829ef73800 cfree+0x0 (/lib/libc-2.32.so)
                 uname   428 10394.179278:    4079859 cpu_atom/cpu-cycles/:  ffffffff95bae912 vma_interval_tree_remove+0x1f2 ([kernel.kallsyms])
      
      Signed-off-by: default avatarAdrian Hunter <adrian.hunter@intel.com>
      Reviewed-by: default avatarKan Liang <kan.liang@linux.intel.com>
      Cc: Jin Yao <yao.jin@linux.intel.com>
      Cc: Jiri Olsa <jolsa@redhat.com>
      Link: http://lore.kernel.org/lkml/20210911133053.15682-1-adrian.hunter@intel.com
      
      
      Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      ff6f41fb
    • Ravi Bangoria's avatar
      perf annotate: Fix fused instr logic for assembly functions · 7efbcc8c
      Ravi Bangoria authored
      
      
      Some x86 microarchitectures fuse a subset of cmp/test/ALU instructions
      with branch instructions, and thus perf annotate highlight such valid
      pairs as fused.
      
      When annotated with source, perf uses struct disasm_line to contain
      either source or instruction line from objdump output. Usually, a C
      statement generates multiple instructions which include such
      cmp/test/ALU + branch instruction pairs. But in case of assembly
      function, each individual assembly source line generate one
      instruction.
      
      The 'perf annotate' instruction fusion logic assumes the previous
      disasm_line as the previous instruction line, which is wrong because,
      for assembly function, previous disasm_line contains source line.  And
      thus perf fails to highlight valid fused instruction pairs for assembly
      functions.
      
      Fix it by searching backward until we find an instruction line and
      consider that disasm_line as fused with current branch instruction.
      
      Before:
               │    cmpq    %rcx, RIP+8(%rsp)
          0.00 │      cmp    %rcx,0x88(%rsp)
               │    je      .Lerror_bad_iret      <--- Source line
          0.14 │   ┌──je     b4                   <--- Instruction line
               │   │movl    %ecx, %eax
      
      After:
               │    cmpq    %rcx, RIP+8(%rsp)
          0.00 │   ┌──cmp    %rcx,0x88(%rsp)
               │   │je      .Lerror_bad_iret
          0.14 │   ├──je     b4
               │   │movl    %ecx, %eax
      
      Reviewed-by: default avatarJin Yao <yao.jin@linux.intel.com>
      Signed-off-by: default avatarRavi Bangoria <ravi.bangoria@amd.com>
      Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
      Cc: Jiri Olsa <jolsa@redhat.com>
      Cc: Kim Phillips <kim.phillips@amd.com>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Namhyung Kim <namhyung@kernel.org>
      Link: https //lore.kernel.org/r/20210911043854.8373-1-ravi.bangoria@amd.com
      Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      7efbcc8c
    • Linus Torvalds's avatar
      Merge tag 's390-5.15-3' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux · 93ff9f13
      Linus Torvalds authored
      Pull s390 fixes from Vasily Gorbik:
      
       - Fix potential out-of-range access during secure boot facility
         detection.
      
       - Fully validate the VMA before calling follow_pte() in pci code.
      
       - Remove arch specific WARN_DYNAMIC_STACK config option.
      
       - Fix zcrypto kernel doc comments.
      
       - Update defconfigs.
      
      * tag 's390-5.15-3' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
        s390: remove WARN_DYNAMIC_STACK
        s390/ap: fix kernel doc comments
        s390: update defconfigs
        s390/sclp: fix Secure-IPL facility detection
        s390/pci_mmio: fully validate the VMA before calling follow_pte()
      93ff9f13
    • Linus Torvalds's avatar
      Merge tag 'devicetree-fixes-for-5.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux · d1a88690
      Linus Torvalds authored
      Pull devicetree fixes from Rob Herring:
      
       - Revert fw_devlink tracking 'phy-handle' links. This broke at least a
         few platforms. A better solution is being worked on.
      
       - Add Samsung UFS binding which fell thru the cracks
      
       - Doc reference fixes from Mauro
      
       - Fix for restricted DMA error handling
      
      * tag 'devicetree-fixes-for-5.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux:
        dt-bindings: arm: Fix Toradex compatible typo
        of: restricted dma: Fix condition for rmem init
        dt-bindings: arm: mediatek: mmsys: update mediatek,mmsys.yaml reference
        dt-bindings: net: dsa: sja1105: update nxp,sja1105.yaml reference
        dt-bindings: ufs: Add bindings for Samsung ufs host
        Revert "of: property: fw_devlink: Add support for "phy-handle" property"
      d1a88690
    • Linus Torvalds's avatar
      tgafb: clarify dependencies · cd395d52
      Linus Torvalds authored
      
      
      The TGA boards were based on the DECchip 21030 PCI graphics accelerator
      used mainly for alpha, and existed in a TURBOchannel (TC) version for
      the DECstation (MIPS) workstations.
      
      However, the config option for the TGA code is a bit confused, and says
      
      	depends on FB && (ALPHA || TC)
      
      because people didn't really want to enable the option for random PCI
      environments, so the "ALPHA" stands in for that case (while the TC case
      is then the MIPS DECstation case).
      
      So that config dependency is kind of a mixture of architecture and bus
      choices.  But it's incorrect, in that there were non-PCI-based alpha
      hardware, and then the driver just causes warnings:
      
        drivers/video/fbdev/tgafb.c:1532:13: error: ‘tgafb_unregister’ defined but not used [-Werror=unused-function]
         1532 | static void tgafb_unregister(struct device *dev)
              |             ^~~~~~~~~~~~~~~~
        drivers/video/fbdev/tgafb.c:1387:12: error: ‘tgafb_register’ defined but not used [-Werror=unused-function]
         1387 | static int tgafb_register(struct device *dev)
              |            ^~~~~~~~~~~~~~
      
      so let's make the config option dependencies a bit more explict:
      
      	depends on FB
      	depends on PCI || TC
      	depends on ALPHA || TC
      
      where that first "FB" is the software configuration dependency, the
      second "PCI || TC" is the hardware bus dependency, while that final
      "ALPHA || TC" dependency is the "don't bother asking except for these
      situations.
      
      We could make that third case have "COMPILE_TEST" as an option, and mark
      the register/unregister functions as __maybe_unused, but I'm not sure
      it's really worth it.
      
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      cd395d52
    • Linus Torvalds's avatar
      alpha: make 'Jensen' IO functions build again · cc9d3aaa
      Linus Torvalds authored
      
      
      The Jensen IO functions are overly copmplicated because some of the IO
      addresses refer to special 'local IO' ports, and they get accessed
      differently.
      
      That then makes gcc not actually inline them, and since they were marked
      "extern inline" when included through the regular <asm/io.h> path, and
      then only marked "inline" when included from sys_jensen.c, you never
      necessarily got a body for the IO functions at all.
      
      The intent of the sys_jensen.c code is to actually get the non-inlined
      copy generated, so remove the 'inline' from the magic macro that is
      supposed to sort this all out.
      
      Also, do not mix 'extern inline' functions (that may or may not be
      inlined and will not generate a function body if they are not) with
      'static inline' (that _will_ generate a function body when not inlined).
      Because gcc will complain about this situation:
      
         error: ‘jensen_bus_outb’ is static but used in inline function ‘jensen_outb’ which is not static
      
      because gcc basically doesn't know whether to generate a body for that
      static inline function or not for that call site.
      
      So make all of these use that __EXTERN_INLINE marker.  Gcc will
      generally not inline these things on use, and then generate the function
      body out-of-line in sys_jensen.c.
      
      This makes the core IO functions build for the alpha Jensen config.
      
      Not that the rest then builds, because it turns out Jensen also doesn't
      enable PCI, which then makes other drievrs very unhappy, but that's a
      separate issue.
      
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      cc9d3aaa