<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/arch/powerpc/include/asm, branch v4.9.321</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>powerpc: define get_cycles macro for arch-override</title>
<updated>2022-06-25T09:45:13+00:00</updated>
<author>
<name>Jason A. Donenfeld</name>
<email>Jason@zx2c4.com</email>
</author>
<published>2022-04-23T19:11:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=0cf45867fa6c6accb9c49803b65192c3a50d265f'/>
<id>0cf45867fa6c6accb9c49803b65192c3a50d265f</id>
<content type='text'>
commit 408835832158df0357e18e96da7f2d1ed6b80e7f upstream.

PowerPC defines a get_cycles() function, but it does not do the usual
`#define get_cycles get_cycles` dance, making it impossible for generic
code to see if an arch-specific function was defined. While the
get_cycles() ifdef is not currently used, the following timekeeping
patch in this series will depend on the macro existing (or not existing)
when defining random_get_entropy().

Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Benjamin Herrenschmidt &lt;benh@ozlabs.org&gt;
Cc: Paul Mackerras &lt;paulus@samba.org&gt;
Acked-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 408835832158df0357e18e96da7f2d1ed6b80e7f upstream.

PowerPC defines a get_cycles() function, but it does not do the usual
`#define get_cycles get_cycles` dance, making it impossible for generic
code to see if an arch-specific function was defined. While the
get_cycles() ifdef is not currently used, the following timekeeping
patch in this series will depend on the macro existing (or not existing)
when defining random_get_entropy().

Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Benjamin Herrenschmidt &lt;benh@ozlabs.org&gt;
Cc: Paul Mackerras &lt;paulus@samba.org&gt;
Acked-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc: Use bool in archrandom.h</title>
<updated>2022-06-25T09:45:03+00:00</updated>
<author>
<name>Richard Henderson</name>
<email>richard.henderson@linaro.org</email>
</author>
<published>2020-01-10T14:54:20+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=af98d2ae79f05a725bbd7a608eac4a4e1dbf8fb5'/>
<id>af98d2ae79f05a725bbd7a608eac4a4e1dbf8fb5</id>
<content type='text'>
commit 98dcfce69729f9ce0fb14f96a39bbdba21429597 upstream.

The generic interface uses bool not int; match that.

Reviewed-by: Ard Biesheuvel &lt;ardb@kernel.org&gt;
Signed-off-by: Richard Henderson &lt;rth@twiddle.net&gt;
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
Link: https://lore.kernel.org/r/20200110145422.49141-9-broonie@kernel.org
Signed-off-by: Theodore Ts'o &lt;tytso@mit.edu&gt;
Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 98dcfce69729f9ce0fb14f96a39bbdba21429597 upstream.

The generic interface uses bool not int; match that.

Reviewed-by: Ard Biesheuvel &lt;ardb@kernel.org&gt;
Signed-off-by: Richard Henderson &lt;rth@twiddle.net&gt;
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
Link: https://lore.kernel.org/r/20200110145422.49141-9-broonie@kernel.org
Signed-off-by: Theodore Ts'o &lt;tytso@mit.edu&gt;
Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc: Remove arch_has_random, arch_has_random_seed</title>
<updated>2022-06-25T09:45:03+00:00</updated>
<author>
<name>Richard Henderson</name>
<email>richard.henderson@linaro.org</email>
</author>
<published>2020-01-10T14:54:14+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=3e5c6758b3017ea98c7494a472482d340193d5d1'/>
<id>3e5c6758b3017ea98c7494a472482d340193d5d1</id>
<content type='text'>
commit cbac004995a0ce8453bdc555fab579e2bdb842a6 upstream.

These symbols are currently part of the generic archrandom.h
interface, but are currently unused and can be removed.

Signed-off-by: Richard Henderson &lt;rth@twiddle.net&gt;
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
Link: https://lore.kernel.org/r/20200110145422.49141-3-broonie@kernel.org
Signed-off-by: Theodore Ts'o &lt;tytso@mit.edu&gt;
Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit cbac004995a0ce8453bdc555fab579e2bdb842a6 upstream.

These symbols are currently part of the generic archrandom.h
interface, but are currently unused and can be removed.

Signed-off-by: Richard Henderson &lt;rth@twiddle.net&gt;
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
Link: https://lore.kernel.org/r/20200110145422.49141-3-broonie@kernel.org
Signed-off-by: Theodore Ts'o &lt;tytso@mit.edu&gt;
Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>arch: pgtable: define MAX_POSSIBLE_PHYSMEM_BITS where needed</title>
<updated>2021-11-12T12:18:01+00:00</updated>
<author>
<name>Arnd Bergmann</name>
<email>arnd@arndb.de</email>
</author>
<published>2021-11-03T20:57:14+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=5928b788fa82e736be6c83887ec209ec9d3038b6'/>
<id>5928b788fa82e736be6c83887ec209ec9d3038b6</id>
<content type='text'>
[ Upstream commit cef397038167ac15d085914493d6c86385773709 ]

Stefan Agner reported a bug when using zsram on 32-bit Arm machines
with RAM above the 4GB address boundary:

  Unable to handle kernel NULL pointer dereference at virtual address 00000000
  pgd = a27bd01c
  [00000000] *pgd=236a0003, *pmd=1ffa64003
  Internal error: Oops: 207 [#1] SMP ARM
  Modules linked in: mdio_bcm_unimac(+) brcmfmac cfg80211 brcmutil raspberrypi_hwmon hci_uart crc32_arm_ce bcm2711_thermal phy_generic genet
  CPU: 0 PID: 123 Comm: mkfs.ext4 Not tainted 5.9.6 #1
  Hardware name: BCM2711
  PC is at zs_map_object+0x94/0x338
  LR is at zram_bvec_rw.constprop.0+0x330/0xa64
  pc : [&lt;c0602b38&gt;]    lr : [&lt;c0bda6a0&gt;]    psr: 60000013
  sp : e376bbe0  ip : 00000000  fp : c1e2921c
  r10: 00000002  r9 : c1dda730  r8 : 00000000
  r7 : e8ff7a00  r6 : 00000000  r5 : 02f9ffa0  r4 : e3710000
  r3 : 000fdffe  r2 : c1e0ce80  r1 : ebf979a0  r0 : 00000000
  Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment user
  Control: 30c5383d  Table: 235c2a80  DAC: fffffffd
  Process mkfs.ext4 (pid: 123, stack limit = 0x495a22e6)
  Stack: (0xe376bbe0 to 0xe376c000)

As it turns out, zsram needs to know the maximum memory size, which
is defined in MAX_PHYSMEM_BITS when CONFIG_SPARSEMEM is set, or in
MAX_POSSIBLE_PHYSMEM_BITS on the x86 architecture.

The same problem will be hit on all 32-bit architectures that have a
physical address space larger than 4GB and happen to not enable sparsemem
and include asm/sparsemem.h from asm/pgtable.h.

After the initial discussion, I suggested just always defining
MAX_POSSIBLE_PHYSMEM_BITS whenever CONFIG_PHYS_ADDR_T_64BIT is
set, or provoking a build error otherwise. This addresses all
configurations that can currently have this runtime bug, but
leaves all other configurations unchanged.

I looked up the possible number of bits in source code and
datasheets, here is what I found:

 - on ARC, CONFIG_ARC_HAS_PAE40 controls whether 32 or 40 bits are used
 - on ARM, CONFIG_LPAE enables 40 bit addressing, without it we never
   support more than 32 bits, even though supersections in theory allow
   up to 40 bits as well.
 - on MIPS, some MIPS32r1 or later chips support 36 bits, and MIPS32r5
   XPA supports up to 60 bits in theory, but 40 bits are more than
   anyone will ever ship
 - On PowerPC, there are three different implementations of 36 bit
   addressing, but 32-bit is used without CONFIG_PTE_64BIT
 - On RISC-V, the normal page table format can support 34 bit
   addressing. There is no highmem support on RISC-V, so anything
   above 2GB is unused, but it might be useful to eventually support
   CONFIG_ZRAM for high pages.

Fixes: 61989a80fb3a ("staging: zsmalloc: zsmalloc memory allocation library")
Fixes: 02390b87a945 ("mm/zsmalloc: Prepare to variable MAX_PHYSMEM_BITS")
Acked-by: Thomas Bogendoerfer &lt;tsbogend@alpha.franken.de&gt;
Reviewed-by: Stefan Agner &lt;stefan@agner.ch&gt;
Tested-by: Stefan Agner &lt;stefan@agner.ch&gt;
Acked-by: Mike Rapoport &lt;rppt@linux.ibm.com&gt;
Link: https://lore.kernel.org/linux-mm/bdfa44bf1c570b05d6c70898e2bbb0acf234ecdf.1604762181.git.stefan@agner.ch/
Signed-off-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
[florian: patch arch/powerpc/include/asm/pte-common.h for 4.9.y
removed arch/riscv/include/asm/pgtable.h which does not exist]
Signed-off-by: Florian Fainelli &lt;f.fainelli@gmail.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit cef397038167ac15d085914493d6c86385773709 ]

Stefan Agner reported a bug when using zsram on 32-bit Arm machines
with RAM above the 4GB address boundary:

  Unable to handle kernel NULL pointer dereference at virtual address 00000000
  pgd = a27bd01c
  [00000000] *pgd=236a0003, *pmd=1ffa64003
  Internal error: Oops: 207 [#1] SMP ARM
  Modules linked in: mdio_bcm_unimac(+) brcmfmac cfg80211 brcmutil raspberrypi_hwmon hci_uart crc32_arm_ce bcm2711_thermal phy_generic genet
  CPU: 0 PID: 123 Comm: mkfs.ext4 Not tainted 5.9.6 #1
  Hardware name: BCM2711
  PC is at zs_map_object+0x94/0x338
  LR is at zram_bvec_rw.constprop.0+0x330/0xa64
  pc : [&lt;c0602b38&gt;]    lr : [&lt;c0bda6a0&gt;]    psr: 60000013
  sp : e376bbe0  ip : 00000000  fp : c1e2921c
  r10: 00000002  r9 : c1dda730  r8 : 00000000
  r7 : e8ff7a00  r6 : 00000000  r5 : 02f9ffa0  r4 : e3710000
  r3 : 000fdffe  r2 : c1e0ce80  r1 : ebf979a0  r0 : 00000000
  Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment user
  Control: 30c5383d  Table: 235c2a80  DAC: fffffffd
  Process mkfs.ext4 (pid: 123, stack limit = 0x495a22e6)
  Stack: (0xe376bbe0 to 0xe376c000)

As it turns out, zsram needs to know the maximum memory size, which
is defined in MAX_PHYSMEM_BITS when CONFIG_SPARSEMEM is set, or in
MAX_POSSIBLE_PHYSMEM_BITS on the x86 architecture.

The same problem will be hit on all 32-bit architectures that have a
physical address space larger than 4GB and happen to not enable sparsemem
and include asm/sparsemem.h from asm/pgtable.h.

After the initial discussion, I suggested just always defining
MAX_POSSIBLE_PHYSMEM_BITS whenever CONFIG_PHYS_ADDR_T_64BIT is
set, or provoking a build error otherwise. This addresses all
configurations that can currently have this runtime bug, but
leaves all other configurations unchanged.

I looked up the possible number of bits in source code and
datasheets, here is what I found:

 - on ARC, CONFIG_ARC_HAS_PAE40 controls whether 32 or 40 bits are used
 - on ARM, CONFIG_LPAE enables 40 bit addressing, without it we never
   support more than 32 bits, even though supersections in theory allow
   up to 40 bits as well.
 - on MIPS, some MIPS32r1 or later chips support 36 bits, and MIPS32r5
   XPA supports up to 60 bits in theory, but 40 bits are more than
   anyone will ever ship
 - On PowerPC, there are three different implementations of 36 bit
   addressing, but 32-bit is used without CONFIG_PTE_64BIT
 - On RISC-V, the normal page table format can support 34 bit
   addressing. There is no highmem support on RISC-V, so anything
   above 2GB is unused, but it might be useful to eventually support
   CONFIG_ZRAM for high pages.

Fixes: 61989a80fb3a ("staging: zsmalloc: zsmalloc memory allocation library")
Fixes: 02390b87a945 ("mm/zsmalloc: Prepare to variable MAX_PHYSMEM_BITS")
Acked-by: Thomas Bogendoerfer &lt;tsbogend@alpha.franken.de&gt;
Reviewed-by: Stefan Agner &lt;stefan@agner.ch&gt;
Tested-by: Stefan Agner &lt;stefan@agner.ch&gt;
Acked-by: Mike Rapoport &lt;rppt@linux.ibm.com&gt;
Link: https://lore.kernel.org/linux-mm/bdfa44bf1c570b05d6c70898e2bbb0acf234ecdf.1604762181.git.stefan@agner.ch/
Signed-off-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
[florian: patch arch/powerpc/include/asm/pte-common.h for 4.9.y
removed arch/riscv/include/asm/pgtable.h which does not exist]
Signed-off-by: Florian Fainelli &lt;f.fainelli@gmail.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/ps3: Add dma_mask to ps3_dma_region</title>
<updated>2021-07-20T14:21:12+00:00</updated>
<author>
<name>Geoff Levand</name>
<email>geoff@infradead.org</email>
</author>
<published>2021-06-03T19:17:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=7c4a0c1e82d2694baa39b1dac6057c5d32ecc842'/>
<id>7c4a0c1e82d2694baa39b1dac6057c5d32ecc842</id>
<content type='text'>
[ Upstream commit 9733862e50fdba55e7f1554e4286fcc5302ff28e ]

Commit f959dcd6ddfd29235030e8026471ac1b022ad2b0 (dma-direct: Fix
potential NULL pointer dereference) added a null check on the
dma_mask pointer of the kernel's device structure.

Add a dma_mask variable to the ps3_dma_region structure and set
the device structure's dma_mask pointer to point to this new variable.

Fixes runtime errors like these:
# WARNING: Fixes tag on line 10 doesn't match correct format
# WARNING: Fixes tag on line 10 doesn't match correct format

  ps3_system_bus_match:349: dev=8.0(sb_01), drv=8.0(ps3flash): match
  WARNING: CPU: 0 PID: 1 at kernel/dma/mapping.c:151 .dma_map_page_attrs+0x34/0x1e0
  ps3flash sb_01: ps3stor_setup:193: map DMA region failed

Signed-off-by: Geoff Levand &lt;geoff@infradead.org&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/562d0c9ea0100a30c3b186bcc7adb34b0bbd2cd7.1622746428.git.geoff@infradead.org
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 9733862e50fdba55e7f1554e4286fcc5302ff28e ]

Commit f959dcd6ddfd29235030e8026471ac1b022ad2b0 (dma-direct: Fix
potential NULL pointer dereference) added a null check on the
dma_mask pointer of the kernel's device structure.

Add a dma_mask variable to the ps3_dma_region structure and set
the device structure's dma_mask pointer to point to this new variable.

Fixes runtime errors like these:
# WARNING: Fixes tag on line 10 doesn't match correct format
# WARNING: Fixes tag on line 10 doesn't match correct format

  ps3_system_bus_match:349: dev=8.0(sb_01), drv=8.0(ps3flash): match
  WARNING: CPU: 0 PID: 1 at kernel/dma/mapping.c:151 .dma_map_page_attrs+0x34/0x1e0
  ps3flash sb_01: ps3stor_setup:193: map DMA region failed

Signed-off-by: Geoff Levand &lt;geoff@infradead.org&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/562d0c9ea0100a30c3b186bcc7adb34b0bbd2cd7.1622746428.git.geoff@infradead.org
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/barrier: Avoid collision with clang's __lwsync macro</title>
<updated>2021-07-20T14:21:09+00:00</updated>
<author>
<name>Nathan Chancellor</name>
<email>nathan@kernel.org</email>
</author>
<published>2021-05-28T18:27:52+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=faf519ae07a01d82a64afffe3195a6b5894b15c9'/>
<id>faf519ae07a01d82a64afffe3195a6b5894b15c9</id>
<content type='text'>
commit 015d98149b326e0f1f02e44413112ca8b4330543 upstream.

A change in clang 13 results in the __lwsync macro being defined as
__builtin_ppc_lwsync, which emits 'lwsync' or 'msync' depending on what
the target supports. This breaks the build because of -Werror in
arch/powerpc, along with thousands of warnings:

 In file included from arch/powerpc/kernel/pmc.c:12:
 In file included from include/linux/bug.h:5:
 In file included from arch/powerpc/include/asm/bug.h:109:
 In file included from include/asm-generic/bug.h:20:
 In file included from include/linux/kernel.h:12:
 In file included from include/linux/bitops.h:32:
 In file included from arch/powerpc/include/asm/bitops.h:62:
 arch/powerpc/include/asm/barrier.h:49:9: error: '__lwsync' macro redefined [-Werror,-Wmacro-redefined]
 #define __lwsync()      __asm__ __volatile__ (stringify_in_c(LWSYNC) : : :"memory")
        ^
 &lt;built-in&gt;:308:9: note: previous definition is here
 #define __lwsync __builtin_ppc_lwsync
        ^
 1 error generated.

Undefine this macro so that the runtime patching introduced by
commit 2d1b2027626d ("powerpc: Fixup lwsync at runtime") continues to
work properly with clang and the build no longer breaks.

Cc: stable@vger.kernel.org
Signed-off-by: Nathan Chancellor &lt;nathan@kernel.org&gt;
Reviewed-by: Nick Desaulniers &lt;ndesaulniers@google.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://github.com/ClangBuiltLinux/linux/issues/1386
Link: https://github.com/llvm/llvm-project/commit/62b5df7fe2b3fda1772befeda15598fbef96a614
Link: https://lore.kernel.org/r/20210528182752.1852002-1-nathan@kernel.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 015d98149b326e0f1f02e44413112ca8b4330543 upstream.

A change in clang 13 results in the __lwsync macro being defined as
__builtin_ppc_lwsync, which emits 'lwsync' or 'msync' depending on what
the target supports. This breaks the build because of -Werror in
arch/powerpc, along with thousands of warnings:

 In file included from arch/powerpc/kernel/pmc.c:12:
 In file included from include/linux/bug.h:5:
 In file included from arch/powerpc/include/asm/bug.h:109:
 In file included from include/asm-generic/bug.h:20:
 In file included from include/linux/kernel.h:12:
 In file included from include/linux/bitops.h:32:
 In file included from arch/powerpc/include/asm/bitops.h:62:
 arch/powerpc/include/asm/barrier.h:49:9: error: '__lwsync' macro redefined [-Werror,-Wmacro-redefined]
 #define __lwsync()      __asm__ __volatile__ (stringify_in_c(LWSYNC) : : :"memory")
        ^
 &lt;built-in&gt;:308:9: note: previous definition is here
 #define __lwsync __builtin_ppc_lwsync
        ^
 1 error generated.

Undefine this macro so that the runtime patching introduced by
commit 2d1b2027626d ("powerpc: Fixup lwsync at runtime") continues to
work properly with clang and the build no longer breaks.

Cc: stable@vger.kernel.org
Signed-off-by: Nathan Chancellor &lt;nathan@kernel.org&gt;
Reviewed-by: Nick Desaulniers &lt;ndesaulniers@google.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://github.com/ClangBuiltLinux/linux/issues/1386
Link: https://github.com/llvm/llvm-project/commit/62b5df7fe2b3fda1772befeda15598fbef96a614
Link: https://lore.kernel.org/r/20210528182752.1852002-1-nathan@kernel.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc: Force inlining of cpu_has_feature() to avoid build failure</title>
<updated>2021-04-07T10:05:39+00:00</updated>
<author>
<name>Christophe Leroy</name>
<email>christophe.leroy@csgroup.eu</email>
</author>
<published>2021-03-10T12:10:34+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=420fd37731051fea8b3116e3f4d092feb79945b9'/>
<id>420fd37731051fea8b3116e3f4d092feb79945b9</id>
<content type='text'>
[ Upstream commit eed5fae00593ab9d261a0c1ffc1bdb786a87a55a ]

The code relies on constant folding of cpu_has_feature() based
on possible and always true values as defined per
CPU_FTRS_ALWAYS and CPU_FTRS_POSSIBLE.

Build failure is encountered with for instance
book3e_all_defconfig on kisskb in the AMDGPU driver which uses
cpu_has_feature(CPU_FTR_VSX_COMP) to decide whether calling
kernel_enable_vsx() or not.

The failure is due to cpu_has_feature() not being inlined with
that configuration with gcc 4.9.

In the same way as commit acdad8fb4a15 ("powerpc: Force inlining of
mmu_has_feature to fix build failure"), for inlining of
cpu_has_feature().

Signed-off-by: Christophe Leroy &lt;christophe.leroy@csgroup.eu&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/b231dfa040ce4cc37f702f5c3a595fdeabfe0462.1615378209.git.christophe.leroy@csgroup.eu
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit eed5fae00593ab9d261a0c1ffc1bdb786a87a55a ]

The code relies on constant folding of cpu_has_feature() based
on possible and always true values as defined per
CPU_FTRS_ALWAYS and CPU_FTRS_POSSIBLE.

Build failure is encountered with for instance
book3e_all_defconfig on kisskb in the AMDGPU driver which uses
cpu_has_feature(CPU_FTR_VSX_COMP) to decide whether calling
kernel_enable_vsx() or not.

The failure is due to cpu_has_feature() not being inlined with
that configuration with gcc 4.9.

In the same way as commit acdad8fb4a15 ("powerpc: Force inlining of
mmu_has_feature to fix build failure"), for inlining of
cpu_has_feature().

Signed-off-by: Christophe Leroy &lt;christophe.leroy@csgroup.eu&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/b231dfa040ce4cc37f702f5c3a595fdeabfe0462.1615378209.git.christophe.leroy@csgroup.eu
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/4xx: Fix build errors from mfdcr()</title>
<updated>2021-03-30T12:41:38+00:00</updated>
<author>
<name>Michael Ellerman</name>
<email>mpe@ellerman.id.au</email>
</author>
<published>2021-02-18T12:30:58+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=9113d25060a05e6db046b76b6ef26e4fe64cb9b3'/>
<id>9113d25060a05e6db046b76b6ef26e4fe64cb9b3</id>
<content type='text'>
[ Upstream commit eead089311f4d935ab5d1d8fbb0c42ad44699ada ]

lkp reported a build error in fsp2.o:

  CC      arch/powerpc/platforms/44x/fsp2.o
  {standard input}:577: Error: unsupported relocation against base

Which comes from:

  pr_err("GESR0: 0x%08x\n", mfdcr(base + PLB4OPB_GESR0));

Where our mfdcr() macro is stringifying "base + PLB4OPB_GESR0", and
passing that to the assembler, which obviously doesn't work.

The mfdcr() macro already checks that the argument is constant using
__builtin_constant_p(), and if not calls the out-of-line version of
mfdcr(). But in this case GCC is smart enough to notice that "base +
PLB4OPB_GESR0" will be constant, even though it's not something we can
immediately stringify into a register number.

Segher pointed out that passing the register number to the inline asm
as a constant would be better, and in fact it fixes the build error,
presumably because it gives GCC a chance to resolve the value.

While we're at it, change mtdcr() similarly.

Reported-by: kernel test robot &lt;lkp@intel.com&gt;
Suggested-by: Segher Boessenkool &lt;segher@kernel.crashing.org&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Acked-by: Feng Tang &lt;feng.tang@intel.com&gt;
Link: https://lore.kernel.org/r/20210218123058.748882-1-mpe@ellerman.id.au
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit eead089311f4d935ab5d1d8fbb0c42ad44699ada ]

lkp reported a build error in fsp2.o:

  CC      arch/powerpc/platforms/44x/fsp2.o
  {standard input}:577: Error: unsupported relocation against base

Which comes from:

  pr_err("GESR0: 0x%08x\n", mfdcr(base + PLB4OPB_GESR0));

Where our mfdcr() macro is stringifying "base + PLB4OPB_GESR0", and
passing that to the assembler, which obviously doesn't work.

The mfdcr() macro already checks that the argument is constant using
__builtin_constant_p(), and if not calls the out-of-line version of
mfdcr(). But in this case GCC is smart enough to notice that "base +
PLB4OPB_GESR0" will be constant, even though it's not something we can
immediately stringify into a register number.

Segher pointed out that passing the register number to the inline asm
as a constant would be better, and in fact it fixes the build error,
presumably because it gives GCC a chance to resolve the value.

While we're at it, change mtdcr() similarly.

Reported-by: kernel test robot &lt;lkp@intel.com&gt;
Suggested-by: Segher Boessenkool &lt;segher@kernel.crashing.org&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Acked-by: Feng Tang &lt;feng.tang@intel.com&gt;
Link: https://lore.kernel.org/r/20210218123058.748882-1-mpe@ellerman.id.au
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/64s: Fix instruction encoding for lis in ppc_function_entry()</title>
<updated>2021-03-17T15:10:18+00:00</updated>
<author>
<name>Naveen N. Rao</name>
<email>naveen.n.rao@linux.vnet.ibm.com</email>
</author>
<published>2021-03-04T02:04:11+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=3d8ca21dc4cc67306374d9143d832ae0c2ae4fab'/>
<id>3d8ca21dc4cc67306374d9143d832ae0c2ae4fab</id>
<content type='text'>
commit cea15316ceee2d4a51dfdecd79e08a438135416c upstream.

'lis r2,N' is 'addis r2,0,N' and the instruction encoding in the macro
LIS_R2 is incorrect (it currently maps to 'addis r0,r2,N'). Fix the
same.

Fixes: c71b7eff426f ("powerpc: Add ABIv2 support to ppc_function_entry")
Cc: stable@vger.kernel.org # v3.16+
Reported-by: Jiri Olsa &lt;jolsa@redhat.com&gt;
Signed-off-by: Naveen N. Rao &lt;naveen.n.rao@linux.vnet.ibm.com&gt;
Acked-by: Segher Boessenkool &lt;segher@kernel.crashing.org&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/20210304020411.16796-1-naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit cea15316ceee2d4a51dfdecd79e08a438135416c upstream.

'lis r2,N' is 'addis r2,0,N' and the instruction encoding in the macro
LIS_R2 is incorrect (it currently maps to 'addis r0,r2,N'). Fix the
same.

Fixes: c71b7eff426f ("powerpc: Add ABIv2 support to ppc_function_entry")
Cc: stable@vger.kernel.org # v3.16+
Reported-by: Jiri Olsa &lt;jolsa@redhat.com&gt;
Signed-off-by: Naveen N. Rao &lt;naveen.n.rao@linux.vnet.ibm.com&gt;
Acked-by: Segher Boessenkool &lt;segher@kernel.crashing.org&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/20210304020411.16796-1-naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc: Fix incorrect stw{, ux, u, x} instructions in __set_pte_at</title>
<updated>2021-01-17T12:57:53+00:00</updated>
<author>
<name>Mathieu Desnoyers</name>
<email>mathieu.desnoyers@efficios.com</email>
</author>
<published>2021-01-13T07:12:44+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=97d987efb3b36c2684006431b8ef2fa8376a1b0d'/>
<id>97d987efb3b36c2684006431b8ef2fa8376a1b0d</id>
<content type='text'>
[ Upstream commit d85be8a49e733dcd23674aa6202870d54bf5600d ]

The placeholder for instruction selection should use the second
argument's operand, which is %1, not %0. This could generate incorrect
assembly code if the memory addressing of operand %0 is a different
form from that of operand %1.

Also remove the %Un placeholder because having %Un placeholders
for two operands which are based on the same local var (ptep) doesn't
make much sense. By the way, it doesn't change the current behaviour
because "&lt;&gt;" constraint is missing for the associated "=m".

[chleroy: revised commit log iaw segher's comments and removed %U0]

Fixes: 9bf2b5cdc5fe ("powerpc: Fixes for CONFIG_PTE_64BIT for SMP support")
Cc: &lt;stable@vger.kernel.org&gt; # v2.6.28+
Signed-off-by: Mathieu Desnoyers &lt;mathieu.desnoyers@efficios.com&gt;
Signed-off-by: Christophe Leroy &lt;christophe.leroy@csgroup.eu&gt;
Acked-by: Segher Boessenkool &lt;segher@kernel.crashing.org&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/96354bd77977a6a933fe9020da57629007fdb920.1603358942.git.christophe.leroy@csgroup.eu
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit d85be8a49e733dcd23674aa6202870d54bf5600d ]

The placeholder for instruction selection should use the second
argument's operand, which is %1, not %0. This could generate incorrect
assembly code if the memory addressing of operand %0 is a different
form from that of operand %1.

Also remove the %Un placeholder because having %Un placeholders
for two operands which are based on the same local var (ptep) doesn't
make much sense. By the way, it doesn't change the current behaviour
because "&lt;&gt;" constraint is missing for the associated "=m".

[chleroy: revised commit log iaw segher's comments and removed %U0]

Fixes: 9bf2b5cdc5fe ("powerpc: Fixes for CONFIG_PTE_64BIT for SMP support")
Cc: &lt;stable@vger.kernel.org&gt; # v2.6.28+
Signed-off-by: Mathieu Desnoyers &lt;mathieu.desnoyers@efficios.com&gt;
Signed-off-by: Christophe Leroy &lt;christophe.leroy@csgroup.eu&gt;
Acked-by: Segher Boessenkool &lt;segher@kernel.crashing.org&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/96354bd77977a6a933fe9020da57629007fdb920.1603358942.git.christophe.leroy@csgroup.eu
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
