<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/arch/riscv/include, branch v5.14</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>riscv: Get rid of CONFIG_PHYS_RAM_BASE in kernel physical address conversion</title>
<updated>2021-08-07T05:41:28+00:00</updated>
<author>
<name>Alexandre Ghiti</name>
<email>alex@ghiti.fr</email>
</author>
<published>2021-07-21T07:59:35+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=6d7f91d914bc90a15ebc426440c26081337ceaa1'/>
<id>6d7f91d914bc90a15ebc426440c26081337ceaa1</id>
<content type='text'>
The usage of CONFIG_PHYS_RAM_BASE for all kernel types was a mistake:
this value is implementation-specific and this breaks the genericity of
the RISC-V kernel.

Fix this by introducing a new variable phys_ram_base that holds this
value at runtime and use it in the kernel physical address conversion
macro. Since this value is used only for XIP kernels, evaluate it only if
CONFIG_XIP_KERNEL is set which in addition optimizes this macro for
standard kernels at compile-time.

Signed-off-by: Alexandre Ghiti &lt;alex@ghiti.fr&gt;
Tested-by: Emil Renner Berthing &lt;kernel@esmil.dk&gt;
Reviewed-by: Jisheng Zhang &lt;jszhang@kernel.org&gt;
Fixes: 44c922572952 ("RISC-V: enable XIP")
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt &lt;palmerdabbelt@google.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The usage of CONFIG_PHYS_RAM_BASE for all kernel types was a mistake:
this value is implementation-specific and this breaks the genericity of
the RISC-V kernel.

Fix this by introducing a new variable phys_ram_base that holds this
value at runtime and use it in the kernel physical address conversion
macro. Since this value is used only for XIP kernels, evaluate it only if
CONFIG_XIP_KERNEL is set which in addition optimizes this macro for
standard kernels at compile-time.

Signed-off-by: Alexandre Ghiti &lt;alex@ghiti.fr&gt;
Tested-by: Emil Renner Berthing &lt;kernel@esmil.dk&gt;
Reviewed-by: Jisheng Zhang &lt;jszhang@kernel.org&gt;
Fixes: 44c922572952 ("RISC-V: enable XIP")
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt &lt;palmerdabbelt@google.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>RISC-V: load initrd wherever it fits into memory</title>
<updated>2021-07-22T05:58:17+00:00</updated>
<author>
<name>Heinrich Schuchardt</name>
<email>xypron.glpk@gmx.de</email>
</author>
<published>2021-06-29T13:40:18+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=c79e89ecaa246c880292ba68cbe08c9c30db77e3'/>
<id>c79e89ecaa246c880292ba68cbe08c9c30db77e3</id>
<content type='text'>
Requiring that initrd is loaded below RAM start + 256 MiB led to failure
to boot SUSE Linux with GRUB on QEMU, cf.
https://lists.gnu.org/archive/html/grub-devel/2021-06/msg00037.html

Remove the constraint.

Reported-by: Andreas Schwab &lt;schwab@linux-m68k.org&gt;
Signed-off-by: Heinrich Schuchardt &lt;xypron.glpk@gmx.de&gt;
Reviewed-by: Atish Patra &lt;atish.patra@wdc.com&gt;
Acked-by: Ard Biesheuvel &lt;ardb@kernel.org&gt;
Fixes: d7071743db31 ("RISC-V: Add EFI stub support.")
Signed-off-by: Palmer Dabbelt &lt;palmerdabbelt@google.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Requiring that initrd is loaded below RAM start + 256 MiB led to failure
to boot SUSE Linux with GRUB on QEMU, cf.
https://lists.gnu.org/archive/html/grub-devel/2021-06/msg00037.html

Remove the constraint.

Reported-by: Andreas Schwab &lt;schwab@linux-m68k.org&gt;
Signed-off-by: Heinrich Schuchardt &lt;xypron.glpk@gmx.de&gt;
Reviewed-by: Atish Patra &lt;atish.patra@wdc.com&gt;
Acked-by: Ard Biesheuvel &lt;ardb@kernel.org&gt;
Fixes: d7071743db31 ("RISC-V: Add EFI stub support.")
Signed-off-by: Palmer Dabbelt &lt;palmerdabbelt@google.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'riscv-for-linus-5.14-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux</title>
<updated>2021-07-09T17:36:29+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2021-07-09T17:36:29+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=9b76d71fa8be8c52dbc855ab516754f0c93e2980'/>
<id>9b76d71fa8be8c52dbc855ab516754f0c93e2980</id>
<content type='text'>
Pull RISC-V updates from Palmer Dabbelt:
 "We have a handful of new features for 5.14:

   - Support for transparent huge pages.

   - Support for generic PCI resources mapping.

   - Support for the mem= kernel parameter.

   - Support for KFENCE.

   - A handful of fixes to avoid W+X mappings in the kernel.

   - Support for VMAP_STACK based overflow detection.

   - An optimized copy_{to,from}_user"

* tag 'riscv-for-linus-5.14-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (37 commits)
  riscv: xip: Fix duplicate included asm/pgtable.h
  riscv: Fix PTDUMP output now BPF region moved back to module region
  riscv: __asm_copy_to-from_user: Optimize unaligned memory access and pipeline stall
  riscv: add VMAP_STACK overflow detection
  riscv: ptrace: add argn syntax
  riscv: mm: fix build errors caused by mk_pmd()
  riscv: Introduce structure that group all variables regarding kernel mapping
  riscv: Map the kernel with correct permissions the first time
  riscv: Introduce set_kernel_memory helper
  riscv: Enable KFENCE for riscv64
  RISC-V: Use asm-generic for {in,out}{bwlq}
  riscv: add ASID-based tlbflushing methods
  riscv: pass the mm_struct to __sbi_tlb_flush_range
  riscv: Add mem kernel parameter support
  riscv: Simplify xip and !xip kernel address conversion macros
  riscv: Remove CONFIG_PHYS_RAM_BASE_FIXED
  riscv: Only initialize swiotlb when necessary
  riscv: fix typo in init.c
  riscv: Cleanup unused functions
  riscv: mm: Use better bitmap_zalloc()
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull RISC-V updates from Palmer Dabbelt:
 "We have a handful of new features for 5.14:

   - Support for transparent huge pages.

   - Support for generic PCI resources mapping.

   - Support for the mem= kernel parameter.

   - Support for KFENCE.

   - A handful of fixes to avoid W+X mappings in the kernel.

   - Support for VMAP_STACK based overflow detection.

   - An optimized copy_{to,from}_user"

* tag 'riscv-for-linus-5.14-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (37 commits)
  riscv: xip: Fix duplicate included asm/pgtable.h
  riscv: Fix PTDUMP output now BPF region moved back to module region
  riscv: __asm_copy_to-from_user: Optimize unaligned memory access and pipeline stall
  riscv: add VMAP_STACK overflow detection
  riscv: ptrace: add argn syntax
  riscv: mm: fix build errors caused by mk_pmd()
  riscv: Introduce structure that group all variables regarding kernel mapping
  riscv: Map the kernel with correct permissions the first time
  riscv: Introduce set_kernel_memory helper
  riscv: Enable KFENCE for riscv64
  RISC-V: Use asm-generic for {in,out}{bwlq}
  riscv: add ASID-based tlbflushing methods
  riscv: pass the mm_struct to __sbi_tlb_flush_range
  riscv: Add mem kernel parameter support
  riscv: Simplify xip and !xip kernel address conversion macros
  riscv: Remove CONFIG_PHYS_RAM_BASE_FIXED
  riscv: Only initialize swiotlb when necessary
  riscv: fix typo in init.c
  riscv: Cleanup unused functions
  riscv: mm: Use better bitmap_zalloc()
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>mm: rename pud_page_vaddr to pud_pgtable and make it return pmd_t *</title>
<updated>2021-07-08T18:48:22+00:00</updated>
<author>
<name>Aneesh Kumar K.V</name>
<email>aneesh.kumar@linux.ibm.com</email>
</author>
<published>2021-07-08T01:09:53+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=9cf6fa2458443118b84090aa1bf7a3630b5940e8'/>
<id>9cf6fa2458443118b84090aa1bf7a3630b5940e8</id>
<content type='text'>
No functional change in this patch.

[aneesh.kumar@linux.ibm.com: fix]
  Link: https://lkml.kernel.org/r/87wnqtnb60.fsf@linux.ibm.com
[sfr@canb.auug.org.au: another fix]
  Link: https://lkml.kernel.org/r/20210619134410.89559-1-aneesh.kumar@linux.ibm.com

Link: https://lkml.kernel.org/r/20210615110859.320299-1-aneesh.kumar@linux.ibm.com
Link: https://lore.kernel.org/linuxppc-dev/CAHk-=wi+J+iodze9FtjM3Zi4j4OeS+qqbKxME9QN4roxPEXH9Q@mail.gmail.com/
Signed-off-by: Aneesh Kumar K.V &lt;aneesh.kumar@linux.ibm.com&gt;
Signed-off-by: Stephen Rothwell &lt;sfr@canb.auug.org.au&gt;
Cc: Christophe Leroy &lt;christophe.leroy@csgroup.eu&gt;
Cc: Hugh Dickins &lt;hughd@google.com&gt;
Cc: Joel Fernandes &lt;joel@joelfernandes.org&gt;
Cc: Kalesh Singh &lt;kaleshsingh@google.com&gt;
Cc: Kirill A. Shutemov &lt;kirill.shutemov@linux.intel.com&gt;
Cc: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Cc: Nicholas Piggin &lt;npiggin@gmail.com&gt;
Cc: Stephen Rothwell &lt;sfr@canb.auug.org.au&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
No functional change in this patch.

[aneesh.kumar@linux.ibm.com: fix]
  Link: https://lkml.kernel.org/r/87wnqtnb60.fsf@linux.ibm.com
[sfr@canb.auug.org.au: another fix]
  Link: https://lkml.kernel.org/r/20210619134410.89559-1-aneesh.kumar@linux.ibm.com

Link: https://lkml.kernel.org/r/20210615110859.320299-1-aneesh.kumar@linux.ibm.com
Link: https://lore.kernel.org/linuxppc-dev/CAHk-=wi+J+iodze9FtjM3Zi4j4OeS+qqbKxME9QN4roxPEXH9Q@mail.gmail.com/
Signed-off-by: Aneesh Kumar K.V &lt;aneesh.kumar@linux.ibm.com&gt;
Signed-off-by: Stephen Rothwell &lt;sfr@canb.auug.org.au&gt;
Cc: Christophe Leroy &lt;christophe.leroy@csgroup.eu&gt;
Cc: Hugh Dickins &lt;hughd@google.com&gt;
Cc: Joel Fernandes &lt;joel@joelfernandes.org&gt;
Cc: Kalesh Singh &lt;kaleshsingh@google.com&gt;
Cc: Kirill A. Shutemov &lt;kirill.shutemov@linux.intel.com&gt;
Cc: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Cc: Nicholas Piggin &lt;npiggin@gmail.com&gt;
Cc: Stephen Rothwell &lt;sfr@canb.auug.org.au&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>arch, mm: wire up memfd_secret system call where relevant</title>
<updated>2021-07-08T18:48:21+00:00</updated>
<author>
<name>Mike Rapoport</name>
<email>rppt@linux.ibm.com</email>
</author>
<published>2021-07-08T01:08:11+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=7bb7f2ac24a028b20fca466b9633847b289b156a'/>
<id>7bb7f2ac24a028b20fca466b9633847b289b156a</id>
<content type='text'>
Wire up memfd_secret system call on architectures that define
ARCH_HAS_SET_DIRECT_MAP, namely arm64, risc-v and x86.

Link: https://lkml.kernel.org/r/20210518072034.31572-7-rppt@kernel.org
Signed-off-by: Mike Rapoport &lt;rppt@linux.ibm.com&gt;
Acked-by: Palmer Dabbelt &lt;palmerdabbelt@google.com&gt;
Acked-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Acked-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Acked-by: David Hildenbrand &lt;david@redhat.com&gt;
Acked-by: James Bottomley &lt;James.Bottomley@HansenPartnership.com&gt;
Cc: Alexander Viro &lt;viro@zeniv.linux.org.uk&gt;
Cc: Andy Lutomirski &lt;luto@kernel.org&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Christopher Lameter &lt;cl@linux.com&gt;
Cc: Dan Williams &lt;dan.j.williams@intel.com&gt;
Cc: Dave Hansen &lt;dave.hansen@linux.intel.com&gt;
Cc: David Hildenbrand &lt;david@redhat.com&gt;
Cc: Elena Reshetova &lt;elena.reshetova@intel.com&gt;
Cc: Hagen Paul Pfeifer &lt;hagen@jauu.net&gt;
Cc: "H. Peter Anvin" &lt;hpa@zytor.com&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: James Bottomley &lt;jejb@linux.ibm.com&gt;
Cc: "Kirill A. Shutemov" &lt;kirill@shutemov.name&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Matthew Wilcox &lt;willy@infradead.org&gt;
Cc: Michael Kerrisk &lt;mtk.manpages@gmail.com&gt;
Cc: Palmer Dabbelt &lt;palmer@dabbelt.com&gt;
Cc: Paul Walmsley &lt;paul.walmsley@sifive.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Rick Edgecombe &lt;rick.p.edgecombe@intel.com&gt;
Cc: Roman Gushchin &lt;guro@fb.com&gt;
Cc: Shakeel Butt &lt;shakeelb@google.com&gt;
Cc: Shuah Khan &lt;shuah@kernel.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Tycho Andersen &lt;tycho@tycho.ws&gt;
Cc: Will Deacon &lt;will@kernel.org&gt;
Cc: kernel test robot &lt;lkp@intel.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Wire up memfd_secret system call on architectures that define
ARCH_HAS_SET_DIRECT_MAP, namely arm64, risc-v and x86.

Link: https://lkml.kernel.org/r/20210518072034.31572-7-rppt@kernel.org
Signed-off-by: Mike Rapoport &lt;rppt@linux.ibm.com&gt;
Acked-by: Palmer Dabbelt &lt;palmerdabbelt@google.com&gt;
Acked-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Acked-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Acked-by: David Hildenbrand &lt;david@redhat.com&gt;
Acked-by: James Bottomley &lt;James.Bottomley@HansenPartnership.com&gt;
Cc: Alexander Viro &lt;viro@zeniv.linux.org.uk&gt;
Cc: Andy Lutomirski &lt;luto@kernel.org&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Christopher Lameter &lt;cl@linux.com&gt;
Cc: Dan Williams &lt;dan.j.williams@intel.com&gt;
Cc: Dave Hansen &lt;dave.hansen@linux.intel.com&gt;
Cc: David Hildenbrand &lt;david@redhat.com&gt;
Cc: Elena Reshetova &lt;elena.reshetova@intel.com&gt;
Cc: Hagen Paul Pfeifer &lt;hagen@jauu.net&gt;
Cc: "H. Peter Anvin" &lt;hpa@zytor.com&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: James Bottomley &lt;jejb@linux.ibm.com&gt;
Cc: "Kirill A. Shutemov" &lt;kirill@shutemov.name&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Matthew Wilcox &lt;willy@infradead.org&gt;
Cc: Michael Kerrisk &lt;mtk.manpages@gmail.com&gt;
Cc: Palmer Dabbelt &lt;palmer@dabbelt.com&gt;
Cc: Paul Walmsley &lt;paul.walmsley@sifive.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Rick Edgecombe &lt;rick.p.edgecombe@intel.com&gt;
Cc: Roman Gushchin &lt;guro@fb.com&gt;
Cc: Shakeel Butt &lt;shakeelb@google.com&gt;
Cc: Shuah Khan &lt;shuah@kernel.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Tycho Andersen &lt;tycho@tycho.ws&gt;
Cc: Will Deacon &lt;will@kernel.org&gt;
Cc: kernel test robot &lt;lkp@intel.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>riscv: add VMAP_STACK overflow detection</title>
<updated>2021-07-06T19:11:38+00:00</updated>
<author>
<name>Tong Tiangen</name>
<email>tongtiangen@huawei.com</email>
</author>
<published>2021-06-21T03:28:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=31da94c25aea835ceac00575a9fd206c5a833fed'/>
<id>31da94c25aea835ceac00575a9fd206c5a833fed</id>
<content type='text'>
This patch adds stack overflow detection to riscv, usable when
CONFIG_VMAP_STACK=y.

Overflow is detected in kernel exception entry(kernel/entry.S), if the
kernel stack is overflow and been detected, the overflow handler is
invoked on a per-cpu overflow stack. This approach preserves GPRs and
the original exception information.

The overflow detect is performed before any attempt is made to access
the stack and the principle of stack overflow detection: kernel stacks
are aligned to double their size, enabling overflow to be detected with
a single bit test. For example, a 16K stack is aligned to 32K, ensuring
that bit 14 of the SP must be zero. On an overflow (or underflow), this
bit is flipped. Thus, overflow (of less than the size of the stack) can
be detected by testing whether this bit is set.

This gives us a useful error message on stack overflow, as can be
trigger with the LKDTM overflow test:

[  388.053267] lkdtm: Performing direct entry EXHAUST_STACK
[  388.053663] lkdtm: Calling function with 1024 frame size to depth 32 ...
[  388.054016] lkdtm: loop 32/32 ...
[  388.054186] lkdtm: loop 31/32 ...
[  388.054491] lkdtm: loop 30/32 ...
[  388.054672] lkdtm: loop 29/32 ...
[  388.054859] lkdtm: loop 28/32 ...
[  388.055010] lkdtm: loop 27/32 ...
[  388.055163] lkdtm: loop 26/32 ...
[  388.055309] lkdtm: loop 25/32 ...
[  388.055481] lkdtm: loop 24/32 ...
[  388.055653] lkdtm: loop 23/32 ...
[  388.055837] lkdtm: loop 22/32 ...
[  388.056015] lkdtm: loop 21/32 ...
[  388.056188] lkdtm: loop 20/32 ...
[  388.058145] Insufficient stack space to handle exception!
[  388.058153] Task stack:     [0xffffffd014260000..0xffffffd014264000]
[  388.058160] Overflow stack: [0xffffffe1f8d2c220..0xffffffe1f8d2d220]
[  388.058168] CPU: 0 PID: 89 Comm: bash Not tainted 5.12.0-rc8-dirty #90
[  388.058175] Hardware name: riscv-virtio,qemu (DT)
[  388.058187] epc : number+0x32/0x2c0
[  388.058247]  ra : vsnprintf+0x2ae/0x3f0
[  388.058255] epc : ffffffe0002d38f6 ra : ffffffe0002d814e sp : ffffffd01425ffc0
[  388.058263]  gp : ffffffe0012e4010 tp : ffffffe08014da00 t0 : ffffffd0142606e8
[  388.058271]  t1 : 0000000000000000 t2 : 0000000000000000 s0 : ffffffd014260070
[  388.058303]  s1 : ffffffd014260158 a0 : ffffffd01426015e a1 : ffffffd014260158
[  388.058311]  a2 : 0000000000000013 a3 : ffff0a01ffffff10 a4 : ffffffe000c398e0
[  388.058319]  a5 : 511b02ec65f3e300 a6 : 0000000000a1749a a7 : 0000000000000000
[  388.058327]  s2 : ffffffff000000ff s3 : 00000000ffff0a01 s4 : ffffffe0012e50a8
[  388.058335]  s5 : 0000000000ffff0a s6 : ffffffe0012e50a8 s7 : ffffffe000da1cc0
[  388.058343]  s8 : ffffffffffffffff s9 : ffffffd0142602b0 s10: ffffffd0142602a8
[  388.058351]  s11: ffffffd01426015e t3 : 00000000000f0000 t4 : ffffffffffffffff
[  388.058359]  t5 : 000000000000002f t6 : ffffffd014260158
[  388.058366] status: 0000000000000100 badaddr: ffffffd01425fff8 cause: 000000000000000f
[  388.058374] Kernel panic - not syncing: Kernel stack overflow
[  388.058381] CPU: 0 PID: 89 Comm: bash Not tainted 5.12.0-rc8-dirty #90
[  388.058387] Hardware name: riscv-virtio,qemu (DT)
[  388.058393] Call Trace:
[  388.058400] [&lt;ffffffe000004944&gt;] walk_stackframe+0x0/0xce
[  388.058406] [&lt;ffffffe0006f0b28&gt;] dump_backtrace+0x38/0x46
[  388.058412] [&lt;ffffffe0006f0b46&gt;] show_stack+0x10/0x18
[  388.058418] [&lt;ffffffe0006f3690&gt;] dump_stack+0x74/0x8e
[  388.058424] [&lt;ffffffe0006f0d52&gt;] panic+0xfc/0x2b2
[  388.058430] [&lt;ffffffe0006f0acc&gt;] print_trace_address+0x0/0x24
[  388.058436] [&lt;ffffffe0002d814e&gt;] vsnprintf+0x2ae/0x3f0
[  388.058956] SMP: stopping secondary CPUs

Signed-off-by: Tong Tiangen &lt;tongtiangen@huawei.com&gt;
Reviewed-by: Kefeng Wang &lt;wangkefeng.wang@huawei.com&gt;
Signed-off-by: Palmer Dabbelt &lt;palmerdabbelt@google.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This patch adds stack overflow detection to riscv, usable when
CONFIG_VMAP_STACK=y.

Overflow is detected in kernel exception entry(kernel/entry.S), if the
kernel stack is overflow and been detected, the overflow handler is
invoked on a per-cpu overflow stack. This approach preserves GPRs and
the original exception information.

The overflow detect is performed before any attempt is made to access
the stack and the principle of stack overflow detection: kernel stacks
are aligned to double their size, enabling overflow to be detected with
a single bit test. For example, a 16K stack is aligned to 32K, ensuring
that bit 14 of the SP must be zero. On an overflow (or underflow), this
bit is flipped. Thus, overflow (of less than the size of the stack) can
be detected by testing whether this bit is set.

This gives us a useful error message on stack overflow, as can be
trigger with the LKDTM overflow test:

[  388.053267] lkdtm: Performing direct entry EXHAUST_STACK
[  388.053663] lkdtm: Calling function with 1024 frame size to depth 32 ...
[  388.054016] lkdtm: loop 32/32 ...
[  388.054186] lkdtm: loop 31/32 ...
[  388.054491] lkdtm: loop 30/32 ...
[  388.054672] lkdtm: loop 29/32 ...
[  388.054859] lkdtm: loop 28/32 ...
[  388.055010] lkdtm: loop 27/32 ...
[  388.055163] lkdtm: loop 26/32 ...
[  388.055309] lkdtm: loop 25/32 ...
[  388.055481] lkdtm: loop 24/32 ...
[  388.055653] lkdtm: loop 23/32 ...
[  388.055837] lkdtm: loop 22/32 ...
[  388.056015] lkdtm: loop 21/32 ...
[  388.056188] lkdtm: loop 20/32 ...
[  388.058145] Insufficient stack space to handle exception!
[  388.058153] Task stack:     [0xffffffd014260000..0xffffffd014264000]
[  388.058160] Overflow stack: [0xffffffe1f8d2c220..0xffffffe1f8d2d220]
[  388.058168] CPU: 0 PID: 89 Comm: bash Not tainted 5.12.0-rc8-dirty #90
[  388.058175] Hardware name: riscv-virtio,qemu (DT)
[  388.058187] epc : number+0x32/0x2c0
[  388.058247]  ra : vsnprintf+0x2ae/0x3f0
[  388.058255] epc : ffffffe0002d38f6 ra : ffffffe0002d814e sp : ffffffd01425ffc0
[  388.058263]  gp : ffffffe0012e4010 tp : ffffffe08014da00 t0 : ffffffd0142606e8
[  388.058271]  t1 : 0000000000000000 t2 : 0000000000000000 s0 : ffffffd014260070
[  388.058303]  s1 : ffffffd014260158 a0 : ffffffd01426015e a1 : ffffffd014260158
[  388.058311]  a2 : 0000000000000013 a3 : ffff0a01ffffff10 a4 : ffffffe000c398e0
[  388.058319]  a5 : 511b02ec65f3e300 a6 : 0000000000a1749a a7 : 0000000000000000
[  388.058327]  s2 : ffffffff000000ff s3 : 00000000ffff0a01 s4 : ffffffe0012e50a8
[  388.058335]  s5 : 0000000000ffff0a s6 : ffffffe0012e50a8 s7 : ffffffe000da1cc0
[  388.058343]  s8 : ffffffffffffffff s9 : ffffffd0142602b0 s10: ffffffd0142602a8
[  388.058351]  s11: ffffffd01426015e t3 : 00000000000f0000 t4 : ffffffffffffffff
[  388.058359]  t5 : 000000000000002f t6 : ffffffd014260158
[  388.058366] status: 0000000000000100 badaddr: ffffffd01425fff8 cause: 000000000000000f
[  388.058374] Kernel panic - not syncing: Kernel stack overflow
[  388.058381] CPU: 0 PID: 89 Comm: bash Not tainted 5.12.0-rc8-dirty #90
[  388.058387] Hardware name: riscv-virtio,qemu (DT)
[  388.058393] Call Trace:
[  388.058400] [&lt;ffffffe000004944&gt;] walk_stackframe+0x0/0xce
[  388.058406] [&lt;ffffffe0006f0b28&gt;] dump_backtrace+0x38/0x46
[  388.058412] [&lt;ffffffe0006f0b46&gt;] show_stack+0x10/0x18
[  388.058418] [&lt;ffffffe0006f3690&gt;] dump_stack+0x74/0x8e
[  388.058424] [&lt;ffffffe0006f0d52&gt;] panic+0xfc/0x2b2
[  388.058430] [&lt;ffffffe0006f0acc&gt;] print_trace_address+0x0/0x24
[  388.058436] [&lt;ffffffe0002d814e&gt;] vsnprintf+0x2ae/0x3f0
[  388.058956] SMP: stopping secondary CPUs

Signed-off-by: Tong Tiangen &lt;tongtiangen@huawei.com&gt;
Reviewed-by: Kefeng Wang &lt;wangkefeng.wang@huawei.com&gt;
Signed-off-by: Palmer Dabbelt &lt;palmerdabbelt@google.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>riscv: ptrace: add argn syntax</title>
<updated>2021-07-06T03:53:09+00:00</updated>
<author>
<name>Jeff Xie</name>
<email>chongguiguzi@gmail.com</email>
</author>
<published>2021-06-20T12:01:51+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=70eee556b678d1e4cd4ea6742a577b596963fa25'/>
<id>70eee556b678d1e4cd4ea6742a577b596963fa25</id>
<content type='text'>
This enables ftrace kprobe events to access kernel function
arguments via $argN syntax.

Signed-off-by: Jeff Xie &lt;huan.xie@suse.com&gt;
Signed-off-by: Palmer Dabbelt &lt;palmerdabbelt@google.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This enables ftrace kprobe events to access kernel function
arguments via $argN syntax.

Signed-off-by: Jeff Xie &lt;huan.xie@suse.com&gt;
Signed-off-by: Palmer Dabbelt &lt;palmerdabbelt@google.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>riscv: mm: fix build errors caused by mk_pmd()</title>
<updated>2021-07-06T01:42:31+00:00</updated>
<author>
<name>Nanyong Sun</name>
<email>sunnanyong@huawei.com</email>
</author>
<published>2021-06-17T09:58:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=9eb4fcff220790f4afadf59160f2c696e99f0a84'/>
<id>9eb4fcff220790f4afadf59160f2c696e99f0a84</id>
<content type='text'>
With "riscv: mm: add THP support on 64-bit", mk_pmd() function
introduce build errors,
1.build with CONFIG_ARCH_RV32I=y:
arch/riscv/include/asm/pgtable.h: In function 'mk_pmd':
arch/riscv/include/asm/pgtable.h:513:9: error: implicit declaration of function 'pfn_pmd';
 did you mean 'pfn_pgd'? [-Werror=implicit-function-declaration]

2.build with CONFIG_SPARSEMEM=y &amp;&amp; CONFIG_SPARSEMEM_VMEMMAP=n
arch/riscv/include/asm/pgtable.h: In function 'mk_pmd':
include/asm-generic/memory_model.h:64:14: error: implicit declaration of function 'page_to_section';
 did you mean 'present_section'? [-Werror=implicit-function-declaration]

Move the definition of mk_pmd to pgtable-64.h to fix the first error.
Use macro definition instead of inline function for mk_pmd
to fix the second problem. It is similar to the mk_pte macro.

Reported-by: kernel test robot &lt;lkp@intel.com&gt;
Signed-off-by: Nanyong Sun &lt;sunnanyong@huawei.com&gt;
Tested-by: Geert Uytterhoeven &lt;geert@linux-m68k.org&gt;
Signed-off-by: Palmer Dabbelt &lt;palmerdabbelt@google.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
With "riscv: mm: add THP support on 64-bit", mk_pmd() function
introduce build errors,
1.build with CONFIG_ARCH_RV32I=y:
arch/riscv/include/asm/pgtable.h: In function 'mk_pmd':
arch/riscv/include/asm/pgtable.h:513:9: error: implicit declaration of function 'pfn_pmd';
 did you mean 'pfn_pgd'? [-Werror=implicit-function-declaration]

2.build with CONFIG_SPARSEMEM=y &amp;&amp; CONFIG_SPARSEMEM_VMEMMAP=n
arch/riscv/include/asm/pgtable.h: In function 'mk_pmd':
include/asm-generic/memory_model.h:64:14: error: implicit declaration of function 'page_to_section';
 did you mean 'present_section'? [-Werror=implicit-function-declaration]

Move the definition of mk_pmd to pgtable-64.h to fix the first error.
Use macro definition instead of inline function for mk_pmd
to fix the second problem. It is similar to the mk_pte macro.

Reported-by: kernel test robot &lt;lkp@intel.com&gt;
Signed-off-by: Nanyong Sun &lt;sunnanyong@huawei.com&gt;
Tested-by: Geert Uytterhoeven &lt;geert@linux-m68k.org&gt;
Signed-off-by: Palmer Dabbelt &lt;palmerdabbelt@google.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>riscv: Introduce structure that group all variables regarding kernel mapping</title>
<updated>2021-07-06T01:04:00+00:00</updated>
<author>
<name>Alexandre Ghiti</name>
<email>alex@ghiti.fr</email>
</author>
<published>2021-06-17T13:53:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=658e2c5125bbbc9b9b5eac23b3c35b87df3c30b8'/>
<id>658e2c5125bbbc9b9b5eac23b3c35b87df3c30b8</id>
<content type='text'>
We have a lot of variables that are used to hold kernel mapping addresses,
offsets between physical and virtual mappings and some others used for XIP
kernels: they are all defined at different places in mm/init.c, so group
them into a single structure with, for some of them, more explicit and concise
names.

Signed-off-by: Alexandre Ghiti &lt;alex@ghiti.fr&gt;
Signed-off-by: Palmer Dabbelt &lt;palmerdabbelt@google.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
We have a lot of variables that are used to hold kernel mapping addresses,
offsets between physical and virtual mappings and some others used for XIP
kernels: they are all defined at different places in mm/init.c, so group
them into a single structure with, for some of them, more explicit and concise
names.

Signed-off-by: Alexandre Ghiti &lt;alex@ghiti.fr&gt;
Signed-off-by: Palmer Dabbelt &lt;palmerdabbelt@google.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'akpm' (patches from Andrew)</title>
<updated>2021-07-02T19:08:10+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2021-07-02T19:08:10+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=71bd9341011f626d692aabe024f099820f02c497'/>
<id>71bd9341011f626d692aabe024f099820f02c497</id>
<content type='text'>
Merge more updates from Andrew Morton:
 "190 patches.

  Subsystems affected by this patch series: mm (hugetlb, userfaultfd,
  vmscan, kconfig, proc, z3fold, zbud, ras, mempolicy, memblock,
  migration, thp, nommu, kconfig, madvise, memory-hotplug, zswap,
  zsmalloc, zram, cleanups, kfence, and hmm), procfs, sysctl, misc,
  core-kernel, lib, lz4, checkpatch, init, kprobes, nilfs2, hfs,
  signals, exec, kcov, selftests, compress/decompress, and ipc"

* emailed patches from Andrew Morton &lt;akpm@linux-foundation.org&gt;: (190 commits)
  ipc/util.c: use binary search for max_idx
  ipc/sem.c: use READ_ONCE()/WRITE_ONCE() for use_global_lock
  ipc: use kmalloc for msg_queue and shmid_kernel
  ipc sem: use kvmalloc for sem_undo allocation
  lib/decompressors: remove set but not used variabled 'level'
  selftests/vm/pkeys: exercise x86 XSAVE init state
  selftests/vm/pkeys: refill shadow register after implicit kernel write
  selftests/vm/pkeys: handle negative sys_pkey_alloc() return code
  selftests/vm/pkeys: fix alloc_random_pkey() to make it really, really random
  kcov: add __no_sanitize_coverage to fix noinstr for all architectures
  exec: remove checks in __register_bimfmt()
  x86: signal: don't do sas_ss_reset() until we are certain that sigframe won't be abandoned
  hfsplus: report create_date to kstat.btime
  hfsplus: remove unnecessary oom message
  nilfs2: remove redundant continue statement in a while-loop
  kprobes: remove duplicated strong free_insn_page in x86 and s390
  init: print out unknown kernel parameters
  checkpatch: do not complain about positive return values starting with EPOLL
  checkpatch: improve the indented label test
  checkpatch: scripts/spdxcheck.py now requires python3
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Merge more updates from Andrew Morton:
 "190 patches.

  Subsystems affected by this patch series: mm (hugetlb, userfaultfd,
  vmscan, kconfig, proc, z3fold, zbud, ras, mempolicy, memblock,
  migration, thp, nommu, kconfig, madvise, memory-hotplug, zswap,
  zsmalloc, zram, cleanups, kfence, and hmm), procfs, sysctl, misc,
  core-kernel, lib, lz4, checkpatch, init, kprobes, nilfs2, hfs,
  signals, exec, kcov, selftests, compress/decompress, and ipc"

* emailed patches from Andrew Morton &lt;akpm@linux-foundation.org&gt;: (190 commits)
  ipc/util.c: use binary search for max_idx
  ipc/sem.c: use READ_ONCE()/WRITE_ONCE() for use_global_lock
  ipc: use kmalloc for msg_queue and shmid_kernel
  ipc sem: use kvmalloc for sem_undo allocation
  lib/decompressors: remove set but not used variabled 'level'
  selftests/vm/pkeys: exercise x86 XSAVE init state
  selftests/vm/pkeys: refill shadow register after implicit kernel write
  selftests/vm/pkeys: handle negative sys_pkey_alloc() return code
  selftests/vm/pkeys: fix alloc_random_pkey() to make it really, really random
  kcov: add __no_sanitize_coverage to fix noinstr for all architectures
  exec: remove checks in __register_bimfmt()
  x86: signal: don't do sas_ss_reset() until we are certain that sigframe won't be abandoned
  hfsplus: report create_date to kstat.btime
  hfsplus: remove unnecessary oom message
  nilfs2: remove redundant continue statement in a while-loop
  kprobes: remove duplicated strong free_insn_page in x86 and s390
  init: print out unknown kernel parameters
  checkpatch: do not complain about positive return values starting with EPOLL
  checkpatch: improve the indented label test
  checkpatch: scripts/spdxcheck.py now requires python3
  ...
</pre>
</div>
</content>
</entry>
</feed>
