linux-stable.git/include/linux, branch v6.1.96

x86/cpu: Fix x86_match_cpu() to match just X86_VENDOR_INTEL

2024-06-27T11:46:23+00:00

[ Upstream commit 93022482b2948a9a7e9b5a2bb685f2e1cb4c3348 ]

Code in v6.9 arch/x86/kernel/smpboot.c was changed by commit

  4db64279bc2b ("x86/cpu: Switch to new Intel CPU model defines") from:

  static const struct x86_cpu_id intel_cod_cpu[] = {
          X86_MATCH_INTEL_FAM6_MODEL(HASWELL_X, 0),       /* COD */
          X86_MATCH_INTEL_FAM6_MODEL(BROADWELL_X, 0),     /* COD */
          X86_MATCH_INTEL_FAM6_MODEL(ANY, 1),             /* SNC */	<--- 443
          {}
  };

  static bool match_llc(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o)
  {
          const struct x86_cpu_id *id = x86_match_cpu(intel_cod_cpu);

to:

  static const struct x86_cpu_id intel_cod_cpu[] = {
           X86_MATCH_VFM(INTEL_HASWELL_X,   0),    /* COD */
           X86_MATCH_VFM(INTEL_BROADWELL_X, 0),    /* COD */
           X86_MATCH_VFM(INTEL_ANY,         1),    /* SNC */
           {}
   };

  static bool match_llc(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o)
  {
          const struct x86_cpu_id *id = x86_match_cpu(intel_cod_cpu);

On an Intel CPU with SNC enabled this code previously matched the rule on line
443 to avoid printing messages about insane cache configuration.  The new code
did not match any rules.

Expanding the macros for the intel_cod_cpu[] array shows that the old is
equivalent to:

  static const struct x86_cpu_id intel_cod_cpu[] = {
  [0] = { .vendor = 0, .family = 6, .model = 0x3F, .steppings = 0, .feature = 0, .driver_data = 0 },
  [1] = { .vendor = 0, .family = 6, .model = 0x4F, .steppings = 0, .feature = 0, .driver_data = 0 },
  [2] = { .vendor = 0, .family = 6, .model = 0x00, .steppings = 0, .feature = 0, .driver_data = 1 },
  [3] = { .vendor = 0, .family = 0, .model = 0x00, .steppings = 0, .feature = 0, .driver_data = 0 }
  }

while the new code expands to:

  static const struct x86_cpu_id intel_cod_cpu[] = {
  [0] = { .vendor = 0, .family = 6, .model = 0x3F, .steppings = 0, .feature = 0, .driver_data = 0 },
  [1] = { .vendor = 0, .family = 6, .model = 0x4F, .steppings = 0, .feature = 0, .driver_data = 0 },
  [2] = { .vendor = 0, .family = 0, .model = 0x00, .steppings = 0, .feature = 0, .driver_data = 1 },
  [3] = { .vendor = 0, .family = 0, .model = 0x00, .steppings = 0, .feature = 0, .driver_data = 0 }
  }

Looking at the code for x86_match_cpu():

  const struct x86_cpu_id *x86_match_cpu(const struct x86_cpu_id *match)
  {
           const struct x86_cpu_id *m;
           struct cpuinfo_x86 *c = &boot_cpu_data;

           for (m = match;
                m->vendor | m->family | m->model | m->steppings | m->feature;
                m++) {
       		...
           }
           return NULL;

it is clear that there was no match because the ANY entry in the table (array
index 2) is now the loop termination condition (all of vendor, family, model,
steppings, and feature are zero).

So this code was working before because the "ANY" check was looking for any
Intel CPU in family 6. But fails now because the family is a wild card. So the
root cause is that x86_match_cpu() has never been able to match on a rule with
just X86_VENDOR_INTEL and all other fields set to wildcards.

Add a new flags field to struct x86_cpu_id that has a bit set to indicate that
this entry in the array is valid. Update X86_MATCH*() macros to set that bit.
Change the end-marker check in x86_match_cpu() to just check the flags field
for this bit.

Backporter notes: The commit in Fixes is really the one that is broken:
you can't have m->vendor as part of the loop termination conditional in
x86_match_cpu() because it can happen - as it has happened above
- that that whole conditional is 0 albeit vendor == 0 is a valid case
- X86_VENDOR_INTEL is 0.

However, the only case where the above happens is the SNC check added by
4db64279bc2b1 so you only need this fix if you have backported that
other commit

  4db64279bc2b ("x86/cpu: Switch to new Intel CPU model defines")

Fixes: 644e9cbbe3fc ("Add driver auto probing for x86 features v4")
Suggested-by: Thomas Gleixner 
Suggested-by: Borislav Petkov 
Signed-off-by: Tony Luck 
Signed-off-by: Borislav Petkov (AMD) 
Cc:  # see above
Link: https://lore.kernel.org/r/20240517144312.GBZkdtAOuJZCvxhFbJ@fat_crate.local
Signed-off-by: Sasha Levin

kcov: don't lose track of remote references during softirqs

2024-06-27T11:46:22+00:00

commit 01c8f9806bde438ca1c8cbbc439f0a14a6694f6c upstream.

In kcov_remote_start()/kcov_remote_stop(), we swap the previous KCOV
metadata of the current task into a per-CPU variable.  However, the
kcov_mode_enabled(mode) check is not sufficient in the case of remote KCOV
coverage: current->kcov_mode always remains KCOV_MODE_DISABLED for remote
KCOV objects.

If the original task that has invoked the KCOV_REMOTE_ENABLE ioctl happens
to get interrupted and kcov_remote_start() is called, it ultimately leads
to kcov_remote_stop() NOT restoring the original KCOV reference.  So when
the task exits, all registered remote KCOV handles remain active forever.

The most uncomfortable effect (at least for syzkaller) is that the bug
prevents the reuse of the same /sys/kernel/debug/kcov descriptor.  If
we obtain it in the parent process and then e.g.  drop some
capabilities and continuously fork to execute individual programs, at
some point current->kcov of the forked process is lost,
kcov_task_exit() takes no action, and all KCOV_REMOTE_ENABLE ioctls
calls from subsequent forks fail.

And, yes, the efficiency is also affected if we keep on losing remote
kcov objects.
a) kcov_remote_map keeps on growing forever.
b) (If I'm not mistaken), we're also not freeing the memory referenced
by kcov->area.

Fix it by introducing a special kcov_mode that is assigned to the task
that owns a KCOV remote object.  It makes kcov_mode_enabled() return true
and yet does not trigger coverage collection in __sanitizer_cov_trace_pc()
and write_comp_data().

[nogikh@google.com: replace WRITE_ONCE() with an ordinary assignment]
  Link: https://lkml.kernel.org/r/20240614171221.2837584-1-nogikh@google.com
Link: https://lkml.kernel.org/r/20240611133229.527822-1-nogikh@google.com
Fixes: 5ff3b30ab57d ("kcov: collect coverage from interrupts")
Signed-off-by: Aleksandr Nogikh 
Reviewed-by: Dmitry Vyukov 
Reviewed-by: Andrey Konovalov 
Tested-by: Andrey Konovalov 
Cc: Alexander Potapenko 
Cc: Arnd Bergmann 
Cc: Marco Elver 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Greg Kroah-Hartman

tty: add the option to have a tty reject a new ldisc

2024-06-27T11:46:17+00:00

[ Upstream commit 6bd23e0c2bb6c65d4f5754d1456bc9a4427fc59b ]

... and use it to limit the virtual terminals to just N_TTY.  They are
kind of special, and in particular, the "con_write()" routine violates
the "writes cannot sleep" rule that some ldiscs rely on.

This avoids the

   BUG: sleeping function called from invalid context at kernel/printk/printk.c:2659

when N_GSM has been attached to a virtual console, and gsmld_write()
calls con_write() while holding a spinlock, and con_write() then tries
to get the console lock.

Tested-by: Tetsuo Handa 
Cc: Jiri Slaby 
Cc: Andrew Morton 
Cc: Daniel Starke 
Reported-by: syzbot 
Closes: https://syzkaller.appspot.com/bug?extid=dbac96d8e73b61aa559c
Signed-off-by: Linus Torvalds 
Link: https://lore.kernel.org/r/20240423163339.59780-1-torvalds@linux-foundation.org
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin

serial: core: Add UPIO_UNKNOWN constant for unknown port type

2024-06-21T12:36:00+00:00

[ Upstream commit 79d713baf63c8f23cc58b304c40be33d64a12aaf ]

In some APIs we would like to assign the special value to iotype
and compare against it in another places. Introduce UPIO_UNKNOWN
for this purpose.

Note, we can't use 0, because it's a valid value for IO port access.

Signed-off-by: Andy Shevchenko 
Link: https://lore.kernel.org/r/20240304123035.758700-3-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman 
Stable-dep-of: 87d80bfbd577 ("serial: 8250_dw: Don't use struct dw8250_data outside of 8250_dw")
Signed-off-by: Sasha Levin

net: pse-pd: Use EOPNOTSUPP error code instead of ENOTSUPP

2024-06-21T12:35:51+00:00

[ Upstream commit 144ba8580bcb82b2686c3d1a043299d844b9a682 ]

ENOTSUPP is not a SUSV4 error code, prefer EOPNOTSUPP as reported by
checkpatch script.

Fixes: 18ff0bcda6d1 ("ethtool: add interface to interact with Ethernet Power Equipment")
Reviewed-by: Andrew Lunn 
Acked-by: Oleksij Rempel 
Signed-off-by: Kory Maincent 
Link: https://lore.kernel.org/r/20240610083426.740660-1-kory.maincent@bootlin.com
Signed-off-by: Jakub Kicinski 
Signed-off-by: Sasha Levin

i2c: add fwnode APIs

2024-06-21T12:35:40+00:00

[ Upstream commit 373c612d72461ddaea223592df31e62c934aae61 ]

Add fwnode APIs for finding and getting I2C adapters, which will be
used by the SFP code. These are passed the fwnode corresponding to
the adapter, and return the I2C adapter. It is the responsibility of
the caller to find the appropriate fwnode.

We keep the DT and ACPI interfaces, but where appropriate, recode them
to use the fwnode interfaces internally.

Reviewed-by: Mika Westerberg 
Signed-off-by: Russell King (Oracle) 
Signed-off-by: Wolfram Sang 
Stable-dep-of: 3f858bbf04db ("i2c: acpi: Unbind mux adapters before delete")
Signed-off-by: Sasha Levin

smp: Provide 'setup_max_cpus' definition on UP too

2024-06-16T11:41:42+00:00

commit 3c2f8859ae1ce53f2a89c8e4ca4092101afbff67 upstream.

This was already defined locally by init/main.c, but let's make
it generic, as arch/x86/kernel/cpu/topology.c is going to make
use of it to have more uniform code.

Reviewed-by: Thomas Gleixner 
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar 
Cc: Guenter Roeck 
Signed-off-by: Greg Kroah-Hartman

mmc: core: Add mmc_gpiod_set_cd_config() function

2024-06-16T11:41:35+00:00

commit 63a7cd660246aa36af263b85c33ecc6601bf04be upstream.

Some mmc host drivers may need to fixup a card-detection GPIO's config
to e.g. enable the GPIO controllers builtin pull-up resistor on devices
where the firmware description of the GPIO is broken (e.g. GpioInt with
PullNone instead of PullUp in ACPI DSDT).

Since this is the exception rather then the rule adding a config
parameter to mmc_gpiod_request_cd() seems undesirable, so instead
add a new mmc_gpiod_set_cd_config() function. This is simply a wrapper
to call gpiod_set_config() on the card-detect GPIO acquired through
mmc_gpiod_request_cd().

Reviewed-by: Andy Shevchenko 
Signed-off-by: Hans de Goede 
Acked-by: Adrian Hunter 
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240410191639.526324-2-hdegoede@redhat.com
Signed-off-by: Ulf Hansson 
Signed-off-by: Greg Kroah-Hartman

fpga: region: add owner module and take its refcount

2024-06-12T09:03:39+00:00

[ Upstream commit b7c0e1ecee403a43abc89eb3e75672b01ff2ece9 ]

The current implementation of the fpga region assumes that the low-level
module registers a driver for the parent device and uses its owner pointer
to take the module's refcount. This approach is problematic since it can
lead to a null pointer dereference while attempting to get the region
during programming if the parent device does not have a driver.

To address this problem, add a module owner pointer to the fpga_region
struct and use it to take the module's refcount. Modify the functions for
registering a region to take an additional owner module parameter and
rename them to avoid conflicts. Use the old function names for helper
macros that automatically set the module that registers the region as the
owner. This ensures compatibility with existing low-level control modules
and reduces the chances of registering a region without setting the owner.

Also, update the documentation to keep it consistent with the new interface
for registering an fpga region.

Fixes: 0fa20cdfcc1f ("fpga: fpga-region: device tree control for FPGA")
Suggested-by: Greg Kroah-Hartman 
Suggested-by: Xu Yilun 
Reviewed-by: Russ Weight 
Signed-off-by: Marco Pagani 
Acked-by: Xu Yilun 
Link: https://lore.kernel.org/r/20240419083601.77403-1-marpagan@redhat.com
Signed-off-by: Xu Yilun 
Signed-off-by: Sasha Levin

counter: linux/counter.h: fix Excess kernel-doc description warning

2024-06-12T09:03:34+00:00

[ Upstream commit 416bdb89605d960405178b9bf04df512d1ace1a3 ]

Remove the @priv: line to prevent the kernel-doc warning:

include/linux/counter.h:400: warning: Excess struct member 'priv' description in 'counter_device'

Signed-off-by: Randy Dunlap 
Fixes: f2ee4759fb70 ("counter: remove old and now unused registration API")
Link: https://lore.kernel.org/r/20231223050511.13849-1-rdunlap@infradead.org
Signed-off-by: William Breathitt Gray 
Signed-off-by: Sasha Levin