* Re: [PATCH 19/21] treewide: add checks for the return value of memblock_alloc*()
From: Heiko Carstens @ 2019-01-18 8:43 UTC (permalink / raw)
To: Mike Rapoport
Cc: Rich Felker, linux-ia64, devicetree, Catalin Marinas, x86,
linux-mips, Max Filippov, Guo Ren, sparclinux, Christoph Hellwig,
linux-s390, linux-c6x-dev, Yoshinori Sato, Richard Weinberger,
linux-sh, Russell King, kasan-dev, Geert Uytterhoeven,
Mark Salter, Dennis Zhou, Matt Turner, linux-snps-arc,
uclinux-h8-devel, Petr Mladek, linux-xtensa, linux-alpha,
linux-um, linux-m68k, Rob Herring, Greentime Hu, xen-devel,
Stafford Horne, Guan Xuetao, linux-arm-kernel, Michal Simek,
Tony Luck, linux-mm, Greg Kroah-Hartman, linux-usb, linux-kernel,
Paul Burton, Vineet Gupta, Andrew Morton, linuxppc-dev,
David S. Miller, openrisc
In-Reply-To: <1547646261-32535-20-git-send-email-rppt@linux.ibm.com>
On Wed, Jan 16, 2019 at 03:44:19PM +0200, Mike Rapoport wrote:
> Add check for the return value of memblock_alloc*() functions and call
> panic() in case of error.
> The panic message repeats the one used by panicing memblock allocators with
> adjustment of parameters to include only relevant ones.
>
> The replacement was mostly automated with semantic patches like the one
> below with manual massaging of format strings.
>
> @@
> expression ptr, size, align;
> @@
> ptr = memblock_alloc(size, align);
> + if (!ptr)
> + panic("%s: Failed to allocate %lu bytes align=0x%lx\n", __func__,
> size, align);
>
> Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
...
> diff --git a/arch/s390/numa/toptree.c b/arch/s390/numa/toptree.c
> index 71a608c..0118c77 100644
> --- a/arch/s390/numa/toptree.c
> +++ b/arch/s390/numa/toptree.c
> @@ -31,10 +31,14 @@ struct toptree __ref *toptree_alloc(int level, int id)
> {
> struct toptree *res;
>
> - if (slab_is_available())
> + if (slab_is_available()) {
> res = kzalloc(sizeof(*res), GFP_KERNEL);
> - else
> + } else {
> res = memblock_alloc(sizeof(*res), 8);
> + if (!res)
> + panic("%s: Failed to allocate %zu bytes align=0x%x\n",
> + __func__, sizeof(*res), 8);
> + }
> if (!res)
> return res;
Please remove this hunk, since the code _should_ be able to handle
allocation failures anyway (see end of quoted code).
Otherwise for the s390 bits:
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
^ permalink raw reply
* Re: [PATCH 21/21] memblock: drop memblock_alloc_*_nopanic() variants
From: Greg Kroah-Hartman @ 2019-01-18 8:42 UTC (permalink / raw)
To: Mike Rapoport
Cc: Rich Felker, linux-ia64, devicetree, Catalin Marinas,
Heiko Carstens, x86, linux-mips, Max Filippov, Guo Ren,
sparclinux, Christoph Hellwig, linux-s390, linux-c6x-dev,
Yoshinori Sato, Richard Weinberger, linux-sh, Russell King,
kasan-dev, Geert Uytterhoeven, Mark Salter, Dennis Zhou,
Matt Turner, linux-snps-arc, uclinux-h8-devel, Petr Mladek,
linux-xtensa, linux-alpha, linux-um, linux-m68k, Rob Herring,
Greentime Hu, xen-devel, Stafford Horne, Guan Xuetao,
linux-arm-kernel, Michal Simek, Tony Luck, linux-mm, Vineet Gupta,
linux-usb, linux-kernel, Paul Burton, openrisc, Andrew Morton,
linuxppc-dev, David S. Miller
In-Reply-To: <1547646261-32535-22-git-send-email-rppt@linux.ibm.com>
On Wed, Jan 16, 2019 at 03:44:21PM +0200, Mike Rapoport wrote:
> As all the memblock allocation functions return NULL in case of error
> rather than panic(), the duplicates with _nopanic suffix can be removed.
>
> Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
> ---
> arch/arc/kernel/unwind.c | 3 +--
> arch/sh/mm/init.c | 2 +-
> arch/x86/kernel/setup_percpu.c | 10 +++++-----
> arch/x86/mm/kasan_init_64.c | 14 ++++++++------
> drivers/firmware/memmap.c | 2 +-
> drivers/usb/early/xhci-dbc.c | 2 +-
> include/linux/memblock.h | 35 -----------------------------------
> kernel/dma/swiotlb.c | 2 +-
> kernel/printk/printk.c | 17 +++++++----------
> mm/memblock.c | 35 -----------------------------------
> mm/page_alloc.c | 10 +++++-----
> mm/page_ext.c | 2 +-
> mm/percpu.c | 11 ++++-------
> mm/sparse.c | 6 ++----
> 14 files changed, 37 insertions(+), 114 deletions(-)
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
^ permalink raw reply
* Re: use generic DMA mapping code in powerpc V4
From: Christoph Hellwig @ 2019-01-18 8:35 UTC (permalink / raw)
To: Christian Zigotzky
Cc: linux-arch, Darren Stevens, linux-kernel, Julian Margetson,
linux-mm, iommu, Paul Mackerras, Olof Johansson, linuxppc-dev,
Christoph Hellwig
In-Reply-To: <e9345547-4dc6-747a-29ec-6375dc8bfe83@xenosoft.de>
Hi Christian,
can you check if the debug printks in this patch trigger?
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index 355d16acee6d..e46c9b64ec0d 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -118,8 +118,11 @@ struct page *__dma_direct_alloc_pages(struct device *dev, size_t size,
page = NULL;
}
}
- if (!page)
+ if (!page) {
page = alloc_pages_node(dev_to_node(dev), gfp, page_order);
+ if (!page)
+ pr_warn("failed to allocate memory with gfp 0x%x\n", gfp);
+ }
if (page && !dma_coherent_ok(dev, page_to_phys(page), size)) {
__free_pages(page, page_order);
@@ -139,6 +142,10 @@ struct page *__dma_direct_alloc_pages(struct device *dev, size_t size,
}
}
+ if (!page) {
+ pr_warn("failed to allocate DMA memory!\n");
+ dump_stack();
+ }
return page;
}
^ permalink raw reply related
* Re: ptrace compile failure with gcc-8.2 on 32-bit powerpc
From: Mathieu Malaterre @ 2019-01-18 8:27 UTC (permalink / raw)
To: linuxppc-dev, Meelis Roos, Michael Ellerman
> Yeah I noticed this just yesterday.
Just FYI this has been accepted as regression in gcc, and fixed is
provided for GCC 9.0:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88273
^ permalink raw reply
* Re: [RFC PATCH v2 5/5] powerpc/syscalls: Allow none instead of sys_ni_syscall
From: Firoz Khan @ 2019-01-18 6:40 UTC (permalink / raw)
To: Arnd Bergmann; +Cc: linuxppc-dev
In-Reply-To: <CAK8P3a2EmiT+hEmj40i1ihZM1ecK2Q42zknWNLRbgYeuOyJgrg@mail.gmail.com>
Hi Arnd,
On Wed, 16 Jan 2019 at 19:23, Arnd Bergmann <arnd@arndb.de> wrote:
>
> On Wed, Jan 16, 2019 at 2:27 PM Michael Ellerman <mpe@ellerman.id.au> wrote:
> > @@ -24,28 +24,28 @@
> > 14 common mknod sys_mknod
> > 15 common chmod sys_chmod
> > 16 common lchown sys_lchown
> > -17 common break sys_ni_syscall
> > -18 32 oldstat sys_stat sys_ni_syscall
> > -18 64 oldstat sys_ni_syscall
> > +17 common break none
> > +18 32 oldstat sys_stat none
> > +18 64 oldstat none
>
> The '64 oldstat' line can simply get dropped here, it has no value
> (I failed to notice this earlier).
The initial requirement is to replace uapi and syscalltbl file with
the script as it is.
If I'm right, for oldstat has uapi header and syscalltbl entry is
sys_ni_syscall. So
the above change will replace uapi and syscalltbl as it is.
We'll do a cleanup for all 10 architectures, so that time we can
remove this (and similer)
entries.
Thanks
Firoz
^ permalink raw reply
* Re: [RFC PATCH v2 2/5] powerpc/syscalls: Remove unused offset parameter
From: Firoz Khan @ 2019-01-18 6:33 UTC (permalink / raw)
To: Michael Ellerman; +Cc: linuxppc-dev, Arnd Bergmann
In-Reply-To: <20190116132714.20094-2-mpe@ellerman.id.au>
Hi Michael,
On Wed, 16 Jan 2019 at 18:57, Michael Ellerman <mpe@ellerman.id.au> wrote:
>
> We never pass a value for offset, nor do we need to, so remove the
> offset logic.
The idea behind all these effort is to come up with a common script for alpha,
ia64, m68k, microblaze, mips, parisc, powerpc, sh, sparc and xtensa. If I'm
right, ia64 and mips pass offset and rest of the architecture doesn't. Inorder
to come up with a offset logic to accommodate those 2 archs requirements.
I think x86, arm and s390 can use the same support with minor changes. So
prefix also need to use it.
I already create a patch series for powerpc with unified script. the changes u
suggested will make difficult to make unified script.
Thanks
Firoz
^ permalink raw reply
* Re: [RFC PATCH 4/5] powerpc/syscalls: Allow none instead of sys_ni_syscall
From: Firoz Khan @ 2019-01-18 6:23 UTC (permalink / raw)
To: Michael Ellerman; +Cc: linuxppc-dev, Arnd Bergmann
In-Reply-To: <20190114113620.17558-4-mpe@ellerman.id.au>
Hi Michael,
On Mon, 14 Jan 2019 at 17:06, Michael Ellerman <mpe@ellerman.id.au> wrote:
>
> sys_ni_syscall is the "not-implemented" syscall syscall, which just
> returns -ENOSYS.
>
> But unless you know that it's not obvious what it does, and even if
> you do know what it means it doesn't stand out that well from other
> real syscalls.
>
> So teach the scripts to treat "none" as a synonym for
> "sys_ni_syscall". This makes the table more readable.
The idea of the first patch series for system call table generation support
is to replace uapi and syscall table as it is. That's why u can find places
where sys_ni_syscalls present. I have a plan for cleanup in the uapi header
and syscall table files. By that time all sys_ni_syscall removed from the
table (Hopefully).
I can post the cleanup patch asap.
> + if [ "$t_entry" = "none" ]; then
> + t_entry="sys_ni_syscall"
> + fi
> +
In that case I don't this above change is required.
Thanks
Firoz
^ permalink raw reply
* [PATCH] powerpc/powernv: Force an freset if IODA reset fails
From: Oliver O'Halloran @ 2019-01-18 4:14 UTC (permalink / raw)
To: linuxppc-dev; +Cc: Oliver O'Halloran
The IODA reset can fail in cases where the PHB has encounted a fatal error
during early boot. Typically this is due a malfunctioning device directly below
the root complex, but can occur for other reasons. This patch fixes the problem
by forcing a reset of the PHB if we get an error back from firmware when doing
the IODA reset.
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
---
arch/powerpc/platforms/powernv/pci-ioda.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c
index 1d6406a..53982f8 100644
--- a/arch/powerpc/platforms/powernv/pci-ioda.c
+++ b/arch/powerpc/platforms/powernv/pci-ioda.c
@@ -3943,9 +3943,12 @@ static void __init pnv_pci_init_ioda_phb(struct device_node *np,
* shutdown PCI devices correctly. We already got IODA table
* cleaned out. So we have to issue PHB reset to stop all PCI
* transactions from previous kernel. The ppc_pci_reset_phbs
- * kernel parameter will force this reset too.
+ * kernel parameter will force this reset too. Additionally,
+ * if the IODA reset above failed then use a bigger hammer.
+ * This can happen if we get a PHB fatal error in very early
+ * boot.
*/
- if (is_kdump_kernel() || pci_reset_phbs) {
+ if (is_kdump_kernel() || pci_reset_phbs || rc) {
pr_info(" Issue PHB reset ...\n");
pnv_eeh_phb_reset(hose, EEH_RESET_FUNDAMENTAL);
pnv_eeh_phb_reset(hose, EEH_RESET_DEACTIVATE);
--
2.9.4
^ permalink raw reply related
* Re: [PATCH 0/3] powerpc: some header search path cleanups
From: Masahiro Yamada @ 2019-01-18 2:50 UTC (permalink / raw)
To: linuxppc-dev, Michael Ellerman
Cc: Linux Kbuild mailing list, Linux Kernel Mailing List, kvm-ppc,
Paul Mackerras
In-Reply-To: <1547176954-17739-1-git-send-email-yamada.masahiro@socionext.com>
Hi Michael,
On Fri, Jan 11, 2019 at 2:20 PM Masahiro Yamada
<yamada.masahiro@socionext.com> wrote:
>
> I am trying to get rid of crappy magic from Kbuild core makefiles.
>
> Before that, I want to drop as many useless paths as possible.
> Actually, many Makefiles are adding around pointless options.
>
> This series cleans some powerpc Makefiles.
> (only compile-tested by 0day bot)
Could you apply this series to ppc tree if you are fine with it?
> Masahiro Yamada (3):
> KVM: powerpc: remove -I. header search paths
> powerpc: remove redundant header search path additions
> powerpc: math-emu: remove unneeded header search paths
>
> arch/powerpc/Makefile | 4 ++--
> arch/powerpc/kvm/Makefile | 5 -----
> arch/powerpc/math-emu/Makefile | 2 +-
> 3 files changed, 3 insertions(+), 8 deletions(-)
>
> --
> 2.7.4
>
--
Best Regards
Masahiro Yamada
^ permalink raw reply
* Re: G5 Quad hangs early on 4.20.2 / 5.0-rc2+
From: Paul Mackerras @ 2019-01-18 2:22 UTC (permalink / raw)
To: Tobias Ulmer; +Cc: linuxppc-dev
In-Reply-To: <20190115224945.fvyrjjf3mjywq7u6@atom2.tmux.org>
On Tue, Jan 15, 2019 at 11:49:45PM +0100, Tobias Ulmer wrote:
> Hi,
>
> both the latest stable 4.20.2 and 5.0 rc2+ hang early on the G5 Quad.
Interesting, I just built v4.20 with g5_defconfig for my quad and it
booted just fine. I'll try Linus' latest.
It could be config-related; could you send me your .config (off-list)?
Paul.
^ permalink raw reply
* [PATCH] hugetlb: allow to free gigantic pages regardless of the configuration
From: Alexandre Ghiti @ 2019-01-17 18:39 UTC (permalink / raw)
To: Catalin Marinas, Will Deacon, Benjamin Herrenschmidt,
Paul Mackerras, Michael Ellerman, Martin Schwidefsky,
Heiko Carstens, Thomas Gleixner, Ingo Molnar, Borislav Petkov,
H . Peter Anvin, x86, Alexander Viro, Mike Kravetz,
linux-arm-kernel, linux-kernel, linuxppc-dev, linux-s390,
linux-fsdevel, linux-mm
Cc: hch, linux-riscv, Alexandre Ghiti
From: Alexandre Ghiti <alex@ghiti.fr>
On systems without CMA or (MEMORY_ISOLATION && COMPACTION) activated but
that support gigantic pages, boottime reserved gigantic pages can not be
freed at all. This patchs simply enables the possibility to hand back
those pages to memory allocator.
This commit then renames gigantic_page_supported and
ARCH_HAS_GIGANTIC_PAGE to make them more accurate. Indeed, those values
being false does not mean that the system cannot use gigantic pages: it
just means that runtime allocation of gigantic pages is not supported,
one can still allocate boottime gigantic pages if the architecture supports
it.
Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
---
- Compiled on all architectures
- Tested on riscv architecture
arch/arm64/Kconfig | 2 +-
arch/arm64/include/asm/hugetlb.h | 7 +++--
arch/powerpc/include/asm/book3s/64/hugetlb.h | 4 +--
arch/powerpc/platforms/Kconfig.cputype | 2 +-
arch/s390/Kconfig | 2 +-
arch/s390/include/asm/hugetlb.h | 7 +++--
arch/x86/Kconfig | 2 +-
arch/x86/include/asm/hugetlb.h | 7 +++--
fs/Kconfig | 2 +-
include/linux/gfp.h | 2 +-
mm/hugetlb.c | 43 +++++++++++++++-------------
mm/page_alloc.c | 4 +--
12 files changed, 48 insertions(+), 36 deletions(-)
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index a4168d366127..18239cbd7fcd 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -18,7 +18,7 @@ config ARM64
select ARCH_HAS_FAST_MULTIPLIER
select ARCH_HAS_FORTIFY_SOURCE
select ARCH_HAS_GCOV_PROFILE_ALL
- select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
+ select ARCH_HAS_GIGANTIC_PAGE_RUNTIME_ALLOCATION if (MEMORY_ISOLATION && COMPACTION) || CMA
select ARCH_HAS_KCOV
select ARCH_HAS_MEMBARRIER_SYNC_CORE
select ARCH_HAS_PTE_SPECIAL
diff --git a/arch/arm64/include/asm/hugetlb.h b/arch/arm64/include/asm/hugetlb.h
index fb6609875455..797fc77eabcd 100644
--- a/arch/arm64/include/asm/hugetlb.h
+++ b/arch/arm64/include/asm/hugetlb.h
@@ -65,8 +65,11 @@ extern void set_huge_swap_pte_at(struct mm_struct *mm, unsigned long addr,
#include <asm-generic/hugetlb.h>
-#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
-static inline bool gigantic_page_supported(void) { return true; }
+#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE_RUNTIME_ALLOCATION
+static inline bool gigantic_page_runtime_allocation_supported(void)
+{
+ return true;
+}
#endif
#endif /* __ASM_HUGETLB_H */
diff --git a/arch/powerpc/include/asm/book3s/64/hugetlb.h b/arch/powerpc/include/asm/book3s/64/hugetlb.h
index 5b0177733994..7711f0e2c7e5 100644
--- a/arch/powerpc/include/asm/book3s/64/hugetlb.h
+++ b/arch/powerpc/include/asm/book3s/64/hugetlb.h
@@ -32,8 +32,8 @@ static inline int hstate_get_psize(struct hstate *hstate)
}
}
-#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
-static inline bool gigantic_page_supported(void)
+#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE_RUNTIME_ALLOCATION
+static inline bool gigantic_page_runtime_allocation_supported(void)
{
return true;
}
diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype
index 8c7464c3f27f..779e06bac697 100644
--- a/arch/powerpc/platforms/Kconfig.cputype
+++ b/arch/powerpc/platforms/Kconfig.cputype
@@ -319,7 +319,7 @@ config ARCH_ENABLE_SPLIT_PMD_PTLOCK
config PPC_RADIX_MMU
bool "Radix MMU Support"
depends on PPC_BOOK3S_64
- select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
+ select ARCH_HAS_GIGANTIC_PAGE_RUNTIME_ALLOCATION if (MEMORY_ISOLATION && COMPACTION) || CMA
default y
help
Enable support for the Power ISA 3.0 Radix style MMU. Currently this
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index ed554b09eb3f..6776eef6a9ae 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -69,7 +69,7 @@ config S390
select ARCH_HAS_ELF_RANDOMIZE
select ARCH_HAS_FORTIFY_SOURCE
select ARCH_HAS_GCOV_PROFILE_ALL
- select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
+ select ARCH_HAS_GIGANTIC_PAGE_RUNTIME_ALLOCATION if (MEMORY_ISOLATION && COMPACTION) || CMA
select ARCH_HAS_KCOV
select ARCH_HAS_PTE_SPECIAL
select ARCH_HAS_SET_MEMORY
diff --git a/arch/s390/include/asm/hugetlb.h b/arch/s390/include/asm/hugetlb.h
index 2d1afa58a4b6..57c952f5388e 100644
--- a/arch/s390/include/asm/hugetlb.h
+++ b/arch/s390/include/asm/hugetlb.h
@@ -116,7 +116,10 @@ static inline pte_t huge_pte_modify(pte_t pte, pgprot_t newprot)
return pte_modify(pte, newprot);
}
-#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
-static inline bool gigantic_page_supported(void) { return true; }
+#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE_RUNTIME_ALLOCATION
+static inline bool gigantic_page_runtime_allocation_supported(void)
+{
+ return true;
+}
#endif
#endif /* _ASM_S390_HUGETLB_H */
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 6185d4f33296..a88f5a4311c9 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -23,7 +23,7 @@ config X86_64
def_bool y
depends on 64BIT
# Options that are inherently 64-bit kernel only:
- select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
+ select ARCH_HAS_GIGANTIC_PAGE_RUNTIME_ALLOCATION if (MEMORY_ISOLATION && COMPACTION) || CMA
select ARCH_SUPPORTS_INT128
select ARCH_USE_CMPXCHG_LOCKREF
select HAVE_ARCH_SOFT_DIRTY
diff --git a/arch/x86/include/asm/hugetlb.h b/arch/x86/include/asm/hugetlb.h
index 7469d321f072..5a5e7119ced4 100644
--- a/arch/x86/include/asm/hugetlb.h
+++ b/arch/x86/include/asm/hugetlb.h
@@ -17,8 +17,11 @@ static inline void arch_clear_hugepage_flags(struct page *page)
{
}
-#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
-static inline bool gigantic_page_supported(void) { return true; }
+#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE_RUNTIME_ALLOCATION
+static inline bool gigantic_page_runtime_allocation_supported(void)
+{
+ return true;
+}
#endif
#endif /* _ASM_X86_HUGETLB_H */
diff --git a/fs/Kconfig b/fs/Kconfig
index ac474a61be37..4192d1fde0f0 100644
--- a/fs/Kconfig
+++ b/fs/Kconfig
@@ -207,7 +207,7 @@ config HUGETLB_PAGE
config MEMFD_CREATE
def_bool TMPFS || HUGETLBFS
-config ARCH_HAS_GIGANTIC_PAGE
+config ARCH_HAS_GIGANTIC_PAGE_RUNTIME_ALLOCATION
bool
source "fs/configfs/Kconfig"
diff --git a/include/linux/gfp.h b/include/linux/gfp.h
index 5f5e25fd6149..79ff86fabd42 100644
--- a/include/linux/gfp.h
+++ b/include/linux/gfp.h
@@ -589,8 +589,8 @@ static inline bool pm_suspended_storage(void)
/* The below functions must be run on a range from a single zone. */
extern int alloc_contig_range(unsigned long start, unsigned long end,
unsigned migratetype, gfp_t gfp_mask);
-extern void free_contig_range(unsigned long pfn, unsigned nr_pages);
#endif
+extern void free_contig_range(unsigned long pfn, unsigned int nr_pages);
#ifdef CONFIG_CMA
/* CMA stuff */
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 745088810965..9893ba26b3b8 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -1035,7 +1035,6 @@ static int hstate_next_node_to_free(struct hstate *h, nodemask_t *nodes_allowed)
((node = hstate_next_node_to_free(hs, mask)) || 1); \
nr_nodes--)
-#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
static void destroy_compound_gigantic_page(struct page *page,
unsigned int order)
{
@@ -1058,6 +1057,7 @@ static void free_gigantic_page(struct page *page, unsigned int order)
free_contig_range(page_to_pfn(page), 1 << order);
}
+#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE_RUNTIME_ALLOCATION
static int __alloc_gigantic_page(unsigned long start_pfn,
unsigned long nr_pages, gfp_t gfp_mask)
{
@@ -1143,22 +1143,19 @@ static struct page *alloc_gigantic_page(struct hstate *h, gfp_t gfp_mask,
static void prep_new_huge_page(struct hstate *h, struct page *page, int nid);
static void prep_compound_gigantic_page(struct page *page, unsigned int order);
-#else /* !CONFIG_ARCH_HAS_GIGANTIC_PAGE */
-static inline bool gigantic_page_supported(void) { return false; }
+#else /* !CONFIG_ARCH_HAS_GIGANTIC_PAGE_RUNTIME_ALLOCATION */
+static inline bool gigantic_page_runtime_allocation_supported(void)
+{
+ return false;
+}
static struct page *alloc_gigantic_page(struct hstate *h, gfp_t gfp_mask,
int nid, nodemask_t *nodemask) { return NULL; }
-static inline void free_gigantic_page(struct page *page, unsigned int order) { }
-static inline void destroy_compound_gigantic_page(struct page *page,
- unsigned int order) { }
#endif
static void update_and_free_page(struct hstate *h, struct page *page)
{
int i;
- if (hstate_is_gigantic(h) && !gigantic_page_supported())
- return;
-
h->nr_huge_pages--;
h->nr_huge_pages_node[page_to_nid(page)]--;
for (i = 0; i < pages_per_huge_page(h); i++) {
@@ -2276,13 +2273,20 @@ static int adjust_pool_surplus(struct hstate *h, nodemask_t *nodes_allowed,
}
#define persistent_huge_pages(h) (h->nr_huge_pages - h->surplus_huge_pages)
-static unsigned long set_max_huge_pages(struct hstate *h, unsigned long count,
+static int set_max_huge_pages(struct hstate *h, unsigned long count,
nodemask_t *nodes_allowed)
{
unsigned long min_count, ret;
- if (hstate_is_gigantic(h) && !gigantic_page_supported())
- return h->max_huge_pages;
+ if (hstate_is_gigantic(h) &&
+ !gigantic_page_runtime_allocation_supported()) {
+ spin_lock(&hugetlb_lock);
+ if (count > persistent_huge_pages(h)) {
+ spin_unlock(&hugetlb_lock);
+ return -EINVAL;
+ }
+ goto decrease_pool;
+ }
/*
* Increase the pool size
@@ -2322,6 +2326,7 @@ static unsigned long set_max_huge_pages(struct hstate *h, unsigned long count,
goto out;
}
+decrease_pool:
/*
* Decrease the pool size
* First return free pages to the buddy allocator (being careful
@@ -2350,9 +2355,10 @@ static unsigned long set_max_huge_pages(struct hstate *h, unsigned long count,
break;
}
out:
- ret = persistent_huge_pages(h);
+ h->max_huge_pages = persistent_huge_pages(h);
spin_unlock(&hugetlb_lock);
- return ret;
+
+ return 0;
}
#define HSTATE_ATTR_RO(_name) \
@@ -2404,11 +2410,6 @@ static ssize_t __nr_hugepages_store_common(bool obey_mempolicy,
int err;
NODEMASK_ALLOC(nodemask_t, nodes_allowed, GFP_KERNEL | __GFP_NORETRY);
- if (hstate_is_gigantic(h) && !gigantic_page_supported()) {
- err = -EINVAL;
- goto out;
- }
-
if (nid == NUMA_NO_NODE) {
/*
* global hstate attribute
@@ -2428,7 +2429,9 @@ static ssize_t __nr_hugepages_store_common(bool obey_mempolicy,
} else
nodes_allowed = &node_states[N_MEMORY];
- h->max_huge_pages = set_max_huge_pages(h, count, nodes_allowed);
+ err = set_max_huge_pages(h, count, nodes_allowed);
+ if (err)
+ goto out;
if (nodes_allowed != &node_states[N_MEMORY])
NODEMASK_FREE(nodes_allowed);
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index cde5dac6229a..81b931db85a1 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -8241,8 +8241,9 @@ int alloc_contig_range(unsigned long start, unsigned long end,
pfn_max_align_up(end), migratetype);
return ret;
}
+#endif
-void free_contig_range(unsigned long pfn, unsigned nr_pages)
+void free_contig_range(unsigned long pfn, unsigned int nr_pages)
{
unsigned int count = 0;
@@ -8254,7 +8255,6 @@ void free_contig_range(unsigned long pfn, unsigned nr_pages)
}
WARN(count != 0, "%d pages are still in use!\n", count);
}
-#endif
#ifdef CONFIG_MEMORY_HOTPLUG
/*
--
2.16.2
^ permalink raw reply related
* Re: G5 Quad hangs early on 4.20.2 / 5.0-rc2+
From: Tobias Ulmer @ 2019-01-18 0:51 UTC (permalink / raw)
To: Benjamin Herrenschmidt; +Cc: linuxppc-dev, Rob Herring
In-Reply-To: <ae9672a789b29a546c12149650f0a7f6ab6b762d.camel@kernel.crashing.org>
On Fri, Jan 18, 2019 at 09:32:07AM +1100, Benjamin Herrenschmidt wrote:
> On Thu, 2019-01-17 at 10:42 +0100, Tobias Ulmer wrote:
> > On Wed, Jan 16, 2019 at 12:15:14PM +1100, Benjamin Herrenschmidt wrote:
> > > On Tue, 2019-01-15 at 23:49 +0100, Tobias Ulmer wrote:
> > > > Hi,
> > > >
> > > > both the latest stable 4.20.2 and 5.0 rc2+ hang early on the G5 Quad.
> > > >
> > > > Surely I'm not the first to run into this, but I couldn't find any
> > > > discussion or bug report. Sorry if you're already aware.
> > > >
> > > > You can see it hang here (5.0 rc2+, 4.20.2 is nearly identical) until
> > > > the watchdog triggers a reboot:
> > > >
> > > > https://i.imgur.com/UiCVRuG.jpg
> > > >
...
> I'll be back on monday or tuesday, let me know where you got up to then
> and I'll take it from there. Also email me your .config please.
Hi,
this was caused by 5c63e407aaabb0464236cfc6279a2d79aede7073
(fbdev: Convert to using %pOFn instead of device_node.name)
name can't be NULL into offb_init_fb, there's a printk and the call to
offb_init_palette_hacks where name is matched against OF device names.
With the partial revert below, both 5.0-rc2+ and 4.20 are happy.
diff --git a/drivers/video/fbdev/offb.c b/drivers/video/fbdev/offb.c
index 31f769d67195..77c0a2f45b3b 100644
--- a/drivers/video/fbdev/offb.c
+++ b/drivers/video/fbdev/offb.c
@@ -419,13 +419,9 @@ static void __init offb_init_fb(const char *name,
var = &info->var;
info->par = par;
- if (name) {
- strcpy(fix->id, "OFfb ");
- strncat(fix->id, name, sizeof(fix->id) - sizeof("OFfb "));
- fix->id[sizeof(fix->id) - 1] = '\0';
- } else
- snprintf(fix->id, sizeof(fix->id), "OFfb %pOFn", dp);
-
+ strcpy(fix->id, "OFfb ");
+ strncat(fix->id, name, sizeof(fix->id) - sizeof("OFfb "));
+ fix->id[sizeof(fix->id) - 1] = '\0';
var->xres = var->xres_virtual = width;
var->yres = var->yres_virtual = height;
@@ -648,7 +644,7 @@ static void __init offb_init_nodriver(struct device_node *dp, int no_real_node)
/* kludge for valkyrie */
if (strcmp(dp->name, "valkyrie") == 0)
address += 0x1000;
- offb_init_fb(no_real_node ? "bootx" : NULL,
+ offb_init_fb(no_real_node ? "bootx" : dp->name,
width, height, depth, pitch, address,
foreign_endian, no_real_node ? NULL : dp);
}
^ permalink raw reply related
* Re: G5 Quad hangs early on 4.20.2 / 5.0-rc2+
From: Benjamin Herrenschmidt @ 2019-01-17 22:32 UTC (permalink / raw)
To: Tobias Ulmer; +Cc: linuxppc-dev
In-Reply-To: <20190117094214.26t72sdqknfzxvlx@atom2.tmux.org>
On Thu, 2019-01-17 at 10:42 +0100, Tobias Ulmer wrote:
> On Wed, Jan 16, 2019 at 12:15:14PM +1100, Benjamin Herrenschmidt wrote:
> > On Tue, 2019-01-15 at 23:49 +0100, Tobias Ulmer wrote:
> > > Hi,
> > >
> > > both the latest stable 4.20.2 and 5.0 rc2+ hang early on the G5 Quad.
> > >
> > > Surely I'm not the first to run into this, but I couldn't find any
> > > discussion or bug report. Sorry if you're already aware.
> > >
> > > You can see it hang here (5.0 rc2+, 4.20.2 is nearly identical) until
> > > the watchdog triggers a reboot:
> > >
> > > https://i.imgur.com/UiCVRuG.jpg
> > >
> > > If I had to make an uneducated guess, it seems to boot into the same
> > > codepath twice (mpic was already initialized, then it starts again right
> > > after smp bringup). Maybe on a second CPU?
> > >
> > > To narrow it down a little, my last known good was 4.18.9
> >
> > I don't think it's an MPIC related problem but it does appear to hang
> > about when interrupts get turned on.
>
> When they get turned on for the second time, for some reason. You can see the
> end of the first time just on top of the screen.
No, that top of screen init is something else.
> It repeats part of the startup initialization right after it's done with
> smp bringup.
That's just the BootX console hanging over to the main console and
replaying the messages I think.
> > I have one of these critters in the office, but I'm working remotely
> > this week so I won't be able to dig into this until next week.
> >
> > It might help if you could bisect in the meantime.
>
> I'm bisecting it now, but it's slow going since I don't have much time
> to babysit the machine. The problem shows up somewhere between v4.19 and
> v4.20.
Ok, thanks.
I'll be back on monday or tuesday, let me know where you got up to then
and I'll take it from there. Also email me your .config please.
Cheers,
Ben.
> > Cheers,
> > Ben.
> >
> >
^ permalink raw reply
* Re: [PATCH v3 0/4] Add NXP AUDMIX device and machine drivers
From: Nicolin Chen @ 2019-01-17 22:24 UTC (permalink / raw)
To: Viorel Suman
Cc: Mark Rutland, devicetree@vger.kernel.org,
alsa-devel@alsa-project.org, Timur Tabi, Xiubo Li,
linux-kernel@vger.kernel.org, S.j. Wang,
linuxppc-dev@lists.ozlabs.org, Takashi Iwai, Rob Herring,
Liam Girdwood, Viorel Suman, Cosmin Samoila, Mark Brown,
dl-linux-imx, Fabio Estevam, Jaroslav Kysela, Daniel Baluta
In-Reply-To: <20190117222218.GF16918@Asurada-Nvidia.nvidia.com>
On Thu, Jan 17, 2019 at 02:22:18PM -0800, Nicolin Chen wrote:
> On Thu, Jan 17, 2019 at 12:46:25PM +0000, Viorel Suman wrote:
> > The patchset adds NXP Audio Mixer (AUDMIX) device and machine
> > drivers and related DT bindings documentation.
> >
> > Changes since V2:
> > 1. Moved "dais" node from machine driver DTS node to device driver DTS node
> > as suggested by Rob.
>
> Yea, it makes a lot of sense. Otherwise, since the connection
> between IP blocks is fixed inside the SoC, the virtual sound
> node would need to be put in the soc-level dtsi, which sounds
> odd to me.
>
> > Changes since V1:
> > 1. Original patch split into distinct patches for the device driver and
> > DT binding documentation.
> > 2. Replaced AMIX with AUDMIX in both code and file names as it looks more
> > RM-compliant.
> > 3. Removed polarity control from CPU DAI driver as suggested by Nicolin.
> > 4. Added machine driver and related DT binding documentation.
> >
> > Viorel Suman (4):
> > ASoC: fsl: Add Audio Mixer CPU DAI driver
> > ASoC: add fsl_audmix DT binding documentation
> > ASoC: fsl: Add Audio Mixer machine driver
> > ASoC: add imx-audmix DT binding documentation
>
> Reviewed-by: Nicolin Chen <nicoleotsuka@gmail.com>
Oops. Just saw Rob's new reply. The drivers look good to me though.
^ permalink raw reply
* Re: [PATCH v3 0/4] Add NXP AUDMIX device and machine drivers
From: Nicolin Chen @ 2019-01-17 22:22 UTC (permalink / raw)
To: Viorel Suman
Cc: Mark Rutland, devicetree@vger.kernel.org,
alsa-devel@alsa-project.org, Timur Tabi, Xiubo Li,
linux-kernel@vger.kernel.org, S.j. Wang,
linuxppc-dev@lists.ozlabs.org, Takashi Iwai, Rob Herring,
Liam Girdwood, Viorel Suman, Cosmin Samoila, Mark Brown,
dl-linux-imx, Fabio Estevam, Jaroslav Kysela, Daniel Baluta
In-Reply-To: <1547729177-14317-1-git-send-email-viorel.suman@nxp.com>
On Thu, Jan 17, 2019 at 12:46:25PM +0000, Viorel Suman wrote:
> The patchset adds NXP Audio Mixer (AUDMIX) device and machine
> drivers and related DT bindings documentation.
>
> Changes since V2:
> 1. Moved "dais" node from machine driver DTS node to device driver DTS node
> as suggested by Rob.
Yea, it makes a lot of sense. Otherwise, since the connection
between IP blocks is fixed inside the SoC, the virtual sound
node would need to be put in the soc-level dtsi, which sounds
odd to me.
> Changes since V1:
> 1. Original patch split into distinct patches for the device driver and
> DT binding documentation.
> 2. Replaced AMIX with AUDMIX in both code and file names as it looks more
> RM-compliant.
> 3. Removed polarity control from CPU DAI driver as suggested by Nicolin.
> 4. Added machine driver and related DT binding documentation.
>
> Viorel Suman (4):
> ASoC: fsl: Add Audio Mixer CPU DAI driver
> ASoC: add fsl_audmix DT binding documentation
> ASoC: fsl: Add Audio Mixer machine driver
> ASoC: add imx-audmix DT binding documentation
Reviewed-by: Nicolin Chen <nicoleotsuka@gmail.com>
^ permalink raw reply
* Re: [PATCH] hugetlb: allow to free gigantic pages regardless of the configuration
From: Mike Kravetz @ 2019-01-17 20:09 UTC (permalink / raw)
To: Alexandre Ghiti, Catalin Marinas, Will Deacon,
Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman,
Martin Schwidefsky, Heiko Carstens, Thomas Gleixner, Ingo Molnar,
Borislav Petkov, H . Peter Anvin, x86, Alexander Viro,
linux-arm-kernel, linux-kernel, linuxppc-dev, linux-s390,
linux-fsdevel, linux-mm
Cc: hch, linux-riscv, Alexandre Ghiti
In-Reply-To: <20190117183953.5990-1-aghiti@upmem.com>
On 1/17/19 10:39 AM, Alexandre Ghiti wrote:
> From: Alexandre Ghiti <alex@ghiti.fr>
>
> On systems without CMA or (MEMORY_ISOLATION && COMPACTION) activated but
> that support gigantic pages, boottime reserved gigantic pages can not be
> freed at all. This patchs simply enables the possibility to hand back
> those pages to memory allocator.
>
> This commit then renames gigantic_page_supported and
> ARCH_HAS_GIGANTIC_PAGE to make them more accurate. Indeed, those values
> being false does not mean that the system cannot use gigantic pages: it
> just means that runtime allocation of gigantic pages is not supported,
> one can still allocate boottime gigantic pages if the architecture supports
> it.
>
> Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
Thank you for doing this!
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
> --- a/include/linux/gfp.h
> +++ b/include/linux/gfp.h
> @@ -589,8 +589,8 @@ static inline bool pm_suspended_storage(void)
> /* The below functions must be run on a range from a single zone. */
> extern int alloc_contig_range(unsigned long start, unsigned long end,
> unsigned migratetype, gfp_t gfp_mask);
> -extern void free_contig_range(unsigned long pfn, unsigned nr_pages);
> #endif
> +extern void free_contig_range(unsigned long pfn, unsigned int nr_pages);
I think nr_pages should be an unsigned long in cma_release() and here
as well, but that is beyond the scope of this patch. Most callers of
cma_release pass in a truncated unsigned long. The truncation is unlikely
to cause any issues, just would be nice if types were consistent. I have
a patch to do that as part of a contiguous allocation series that I will
get back to someday.
> @@ -2350,9 +2355,10 @@ static unsigned long set_max_huge_pages(struct hstate *h, unsigned long count,
> break;
> }
> out:
> - ret = persistent_huge_pages(h);
> + h->max_huge_pages = persistent_huge_pages(h);
> spin_unlock(&hugetlb_lock);
> - return ret;
> +
> + return 0;
> }
>
> #define HSTATE_ATTR_RO(_name) \
> @@ -2404,11 +2410,6 @@ static ssize_t __nr_hugepages_store_common(bool obey_mempolicy,
> int err;
> NODEMASK_ALLOC(nodemask_t, nodes_allowed, GFP_KERNEL | __GFP_NORETRY);
>
> - if (hstate_is_gigantic(h) && !gigantic_page_supported()) {
> - err = -EINVAL;
> - goto out;
> - }
> -
> if (nid == NUMA_NO_NODE) {
> /*
> * global hstate attribute
> @@ -2428,7 +2429,9 @@ static ssize_t __nr_hugepages_store_common(bool obey_mempolicy,
> } else
> nodes_allowed = &node_states[N_MEMORY];
>
> - h->max_huge_pages = set_max_huge_pages(h, count, nodes_allowed);
> + err = set_max_huge_pages(h, count, nodes_allowed);
> + if (err)
> + goto out;
>
> if (nodes_allowed != &node_states[N_MEMORY])
> NODEMASK_FREE(nodes_allowed);
Yeah! Those changes causes max_huge_pages to be modified while holding
hugetlb_lock as it should be.
--
Mike Kravetz
^ permalink raw reply
* Re: [PATCH] powerpc/cell: Remove duplicate header
From: Souptick Joarder @ 2019-01-17 17:47 UTC (permalink / raw)
To: Sabyasachi Gupta
Cc: Arnd Bergmann, Brajeswar Ghosh, linux-kernel, paulus,
linuxppc-dev
In-Reply-To: <5c40aafc.1c69fb81.a0ba0.67a7@mx.google.com>
On Thu, Jan 17, 2019 at 9:49 PM Sabyasachi Gupta
<sabyasachi.linux@gmail.com> wrote:
>
> Remove linux/syscalls.h which is included more than once
>
> Signed-off-by: Sabyasachi Gupta <sabyasachi.linux@gmail.com>
Acked-by: Souptick Joarder <jrdr.linux@gmail.com>
> ---
> arch/powerpc/platforms/cell/spu_syscalls.c | 1 -
> 1 file changed, 1 deletion(-)
>
> diff --git a/arch/powerpc/platforms/cell/spu_syscalls.c b/arch/powerpc/platforms/cell/spu_syscalls.c
> index 263413a..b95d6af 100644
> --- a/arch/powerpc/platforms/cell/spu_syscalls.c
> +++ b/arch/powerpc/platforms/cell/spu_syscalls.c
> @@ -26,7 +26,6 @@
> #include <linux/syscalls.h>
> #include <linux/rcupdate.h>
> #include <linux/binfmts.h>
> -#include <linux/syscalls.h>
>
> #include <asm/spu.h>
>
> --
> 2.7.4
>
^ permalink raw reply
* Re: [PATCH 3/3] videobuf2: replace a layering violation with dma_map_resource
From: Christoph Hellwig @ 2019-01-17 17:21 UTC (permalink / raw)
To: Marek Szyprowski
Cc: Niklas Söderlund, Pawel Osciak, Russell King, iommu,
linux-kernel, Kyungmin Park, Mauro Carvalho Chehab, linuxppc-dev,
Christoph Hellwig, linux-arm-kernel, linux-media
In-Reply-To: <6f8892ac-c2aa-10df-c74f-ba032bf75160@samsung.com>
On Mon, Jan 14, 2019 at 01:42:26PM +0100, Marek Szyprowski wrote:
> Hi Christoph,
>
> On 2019-01-11 19:17, Christoph Hellwig wrote:
> > vb2_dc_get_userptr pokes into arm direct mapping details to get the
> > resemblance of a dma address for a a physical address that does is
> > not backed by a page struct. Not only is this not portable to other
> > architectures with dma direct mapping offsets, but also not to uses
> > of IOMMUs of any kind. Switch to the proper dma_map_resource /
> > dma_unmap_resource interface instead.
> >
> > Signed-off-by: Christoph Hellwig <hch@lst.de>
>
> There are checks for IOMMU presence in other places in vb2-dma-contig,
> so it was used only when no IOMMU is available, but I agree that the
> hacky code should be replaced by a generic code if possible.
>
> Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
>
> V4L2 pipeline works fine on older Exynos-based boards with CMA and IOMMU
> disabled.
Do you know if these rely on the offsets? E.g. would they still work
with the patch below applied on top. That would keep the map_resource
semantics as-is as solve the issue pointed out by Robin for now.
If not I can only think of a flag to bypass the offseting for now, but
that would be pretty ugly. Or go for the long-term solution of
discovering the relationship between the two devices, as done by the
PCIe P2P code..
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index 8e0359b04957..25bd19974223 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -359,7 +359,7 @@ EXPORT_SYMBOL(dma_direct_map_sg);
dma_addr_t dma_direct_map_resource(struct device *dev, phys_addr_t paddr,
size_t size, enum dma_data_direction dir, unsigned long attrs)
{
- dma_addr_t dma_addr = phys_to_dma(dev, paddr);
+ dma_addr_t dma_addr = paddr;
if (unlikely(!dma_direct_possible(dev, dma_addr, size))) {
report_addr(dev, dma_addr, size);
^ permalink raw reply related
* [PATCH] Selftests/powerpc: Add a signal fuzzer selftest
From: Breno Leitao @ 2019-01-17 17:01 UTC (permalink / raw)
To: linuxppc-dev; +Cc: mikey, Breno Leitao, gromero
This is a new selftest that raises SIGUSR1 signals and handles it in a set
of different ways, trying to create different scenario for testing
purpose.
This test works raising a signal and calling sigreturn interleaved with
TM operations, as starting, suspending and terminating a transaction. The
test depends on random numbers, and, based on them, it sets different TM
states.
Other than that, the test fills out the user context struct that is passed
to the sigreturn system call with random data, in order to make sure that
the signal handler syscall can handle different and invalid states
properly.
This selftest has command line parameters to control what kind of tests the
user wants to run, as for example, if a transaction should be started prior
to signal being raised, or, after the signal being raised and before the
sigreturn. If no parameter is given, the default is enabling all options.
This test does not check if the user context is being read and set
properly by the kernel. Its purpose, at this time, is basically
guaranteeing that the kernel does not crash on invalid scenarios.
Signed-off-by: Breno Leitao <leitao@debian.org>
---
tools/testing/selftests/powerpc/harness.c | 6 +-
tools/testing/selftests/powerpc/include/reg.h | 2 +
.../testing/selftests/powerpc/signal/Makefile | 3 +-
.../testing/selftests/powerpc/signal/sigfuz.c | 325 ++++++++++++++++++
4 files changed, 333 insertions(+), 3 deletions(-)
create mode 100644 tools/testing/selftests/powerpc/signal/sigfuz.c
diff --git a/tools/testing/selftests/powerpc/harness.c b/tools/testing/selftests/powerpc/harness.c
index 9d7166dfad1e..ba89353abfcc 100644
--- a/tools/testing/selftests/powerpc/harness.c
+++ b/tools/testing/selftests/powerpc/harness.c
@@ -21,6 +21,7 @@
#define KILL_TIMEOUT 5
+/* Setting timeout to -1 disables the alarm */
static uint64_t timeout = 120;
int run_test(int (test_function)(void), char *name)
@@ -43,8 +44,9 @@ int run_test(int (test_function)(void), char *name)
setpgid(pid, pid);
- /* Wake us up in timeout seconds */
- alarm(timeout);
+ if (timeout != -1)
+ /* Wake us up in timeout seconds */
+ alarm(timeout);
terminated = false;
wait:
diff --git a/tools/testing/selftests/powerpc/include/reg.h b/tools/testing/selftests/powerpc/include/reg.h
index a69ab6e2afd9..d577a7ecf3e5 100644
--- a/tools/testing/selftests/powerpc/include/reg.h
+++ b/tools/testing/selftests/powerpc/include/reg.h
@@ -79,11 +79,13 @@
/* MSR register bits */
#define MSR_TS_S_LG 33 /* Trans Mem state: Suspended */
+#define MSR_TS_T_LG 34 /* Trans Mem state: Active */
#define __MASK(X) (1UL<<(X))
/* macros to check TM MSR bits */
#define MSR_TS_S __MASK(MSR_TS_S_LG) /* Transaction Suspended */
+#define MSR_TS_T __MASK(MSR_TS_T_LG) /* Transaction Transactional */
/* Vector Instructions */
#define VSX_XX1(xs, ra, rb) (((xs) & 0x1f) << 21 | ((ra) << 16) | \
diff --git a/tools/testing/selftests/powerpc/signal/Makefile b/tools/testing/selftests/powerpc/signal/Makefile
index 209a958dca12..113838fbbe7f 100644
--- a/tools/testing/selftests/powerpc/signal/Makefile
+++ b/tools/testing/selftests/powerpc/signal/Makefile
@@ -1,8 +1,9 @@
# SPDX-License-Identifier: GPL-2.0
-TEST_GEN_PROGS := signal signal_tm
+TEST_GEN_PROGS := signal signal_tm sigfuz
CFLAGS += -maltivec
$(OUTPUT)/signal_tm: CFLAGS += -mhtm
+$(OUTPUT)/sigfuz: CFLAGS += -pthread -m64
top_srcdir = ../../../../..
include ../../lib.mk
diff --git a/tools/testing/selftests/powerpc/signal/sigfuz.c b/tools/testing/selftests/powerpc/signal/sigfuz.c
new file mode 100644
index 000000000000..d0b9468b2f37
--- /dev/null
+++ b/tools/testing/selftests/powerpc/signal/sigfuz.c
@@ -0,0 +1,325 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2018, Breno Leitao, IBM Corp.
+ * Licensed under GPLv2.
+ *
+ * Sigfuz(tm): A PowerPC TM-aware signal fuzzer.
+ *
+ * This is a new selftest that raises SIGUSR1 signals and handles it in a set
+ * of different ways, trying to create different scenario for testing
+ * purpose.
+ *
+ * This test works raising a signal and calling sigreturn interleaved with
+ * TM operations, as starting, suspending and terminating a transaction. The
+ * test depends on random numbers, and, based on them, it sets different TM
+ * states.
+ *
+ * Other than that, the test fills out the user context struct that is passed
+ * to the sigreturn system call with random data, in order to make sure that
+ * the signal handler syscall can handle different and invalid states
+ * properly.
+ *
+ * This selftest has command line parameters to control what kind of tests the
+ * user wants to run, as for example, if a transaction should be started prior
+ * to signal being raised, or, after the signal being raised and before the
+ * sigreturn. If no parameter is given, the default is enabling all options.
+ *
+ * This test does not check if the user context is being read and set
+ * properly by the kernel. Its purpose, at this time, is basically
+ * guaranteeing that the kernel does not crash on invalid scenarios.
+ */
+
+#include <stdio.h>
+#include <limits.h>
+#include <sys/wait.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <signal.h>
+#include <string.h>
+#include <ucontext.h>
+#include <sys/mman.h>
+#include <pthread.h>
+#include "utils.h"
+
+/* Selftest defaults */
+#define COUNT_MAX 4000 /* Number of interactions */
+#define THREADS 16 /* Number of threads */
+
+/* Arguments options */
+#define ARG_MESS_WITH_TM_AT 0x1
+#define ARG_MESS_WITH_TM_BEFORE 0x2
+#define ARG_MESS_WITH_MSR_AT 0x4
+#define ARG_FOREVER 0x10
+#define ARG_COMPLETE (ARG_MESS_WITH_TM_AT | \
+ ARG_MESS_WITH_TM_BEFORE | \
+ ARG_MESS_WITH_MSR_AT)
+
+static int args;
+static int nthread = THREADS;
+static int count_max = COUNT_MAX;
+
+/* checkpoint context */
+static ucontext_t *tmp_uc;
+
+/* Return true with 1/x probability */
+static int one_in_chance(int x)
+{
+ return rand() % x == 0;
+}
+
+/* Change TM states */
+static void mess_with_tm(void)
+{
+ /* Starts a transaction 33% of the time */
+ if (one_in_chance(3)) {
+ asm ("tbegin. ;"
+ "beq 8 ;");
+
+ /* And suspended half of them */
+ if (one_in_chance(2))
+ asm("tsuspend. ;");
+ }
+
+ /* Call 'tend' in 5% of the runs */
+ if (one_in_chance(20))
+ asm("tend. ;");
+}
+
+/* Signal handler that will be invoked with raise() */
+static void trap_signal_handler(int signo, siginfo_t *si, void *uc)
+{
+ ucontext_t *ucp = uc;
+
+ ucp->uc_link = tmp_uc;
+
+ /*
+ * Set uc_link in three possible ways:
+ * - Setting a single 'int' in the whole chunk
+ * - Cloning ucp into uc_link
+ * - Allocating a new memory chunk
+ */
+ if (one_in_chance(3)) {
+ memset(ucp->uc_link, rand(), sizeof(ucontext_t));
+ } else if (one_in_chance(2)) {
+ memcpy(ucp->uc_link, uc, sizeof(ucontext_t));
+ } else if (one_in_chance(2)) {
+ if (tmp_uc) {
+ free(tmp_uc);
+ tmp_uc = NULL;
+ }
+ tmp_uc = malloc(sizeof(ucontext_t));
+ ucp->uc_link = tmp_uc;
+ /* Trying to cause a major page fault at Kernel level */
+ madvise(ucp->uc_link, sizeof(ucontext_t), MADV_DONTNEED);
+ }
+
+ if (args & ARG_MESS_WITH_MSR_AT) {
+ /* Changing the checkpointed registers */
+ if (one_in_chance(4)) {
+ ucp->uc_link->uc_mcontext.gp_regs[PT_MSR] |= MSR_TS_S;
+ } else {
+ if (one_in_chance(2)) {
+ ucp->uc_link->uc_mcontext.gp_regs[PT_MSR] |=
+ MSR_TS_T;
+ } else if (one_in_chance(2)) {
+ ucp->uc_link->uc_mcontext.gp_regs[PT_MSR] |=
+ MSR_TS_T | MSR_TS_S;
+ }
+ }
+
+ /* Checking the current register context */
+ if (one_in_chance(2)) {
+ ucp->uc_mcontext.gp_regs[PT_MSR] |= MSR_TS_S;
+ } else if (one_in_chance(2)) {
+ if (one_in_chance(2))
+ ucp->uc_mcontext.gp_regs[PT_MSR] |=
+ MSR_TS_T;
+ else if (one_in_chance(2))
+ ucp->uc_mcontext.gp_regs[PT_MSR] |=
+ MSR_TS_T | MSR_TS_S;
+ }
+ }
+
+ if (one_in_chance(20)) {
+ /* Nested transaction start */
+ if (one_in_chance(5))
+ mess_with_tm();
+
+ /* Return without changing any other context info */
+ return;
+ }
+
+ if (one_in_chance(10))
+ ucp->uc_mcontext.gp_regs[PT_MSR] = random();
+ if (one_in_chance(10))
+ ucp->uc_mcontext.gp_regs[PT_NIP] = random();
+ if (one_in_chance(10))
+ ucp->uc_link->uc_mcontext.gp_regs[PT_MSR] = random();
+ if (one_in_chance(10))
+ ucp->uc_link->uc_mcontext.gp_regs[PT_NIP] = random();
+
+ ucp->uc_mcontext.gp_regs[PT_TRAP] = random();
+ ucp->uc_mcontext.gp_regs[PT_DSISR] = random();
+ ucp->uc_mcontext.gp_regs[PT_DAR] = random();
+ ucp->uc_mcontext.gp_regs[PT_ORIG_R3] = random();
+ ucp->uc_mcontext.gp_regs[PT_XER] = random();
+ ucp->uc_mcontext.gp_regs[PT_RESULT] = random();
+ ucp->uc_mcontext.gp_regs[PT_SOFTE] = random();
+ ucp->uc_mcontext.gp_regs[PT_DSCR] = random();
+ ucp->uc_mcontext.gp_regs[PT_CTR] = random();
+ ucp->uc_mcontext.gp_regs[PT_LNK] = random();
+ ucp->uc_mcontext.gp_regs[PT_CCR] = random();
+ ucp->uc_mcontext.gp_regs[PT_REGS_COUNT] = random();
+
+ ucp->uc_link->uc_mcontext.gp_regs[PT_TRAP] = random();
+ ucp->uc_link->uc_mcontext.gp_regs[PT_DSISR] = random();
+ ucp->uc_link->uc_mcontext.gp_regs[PT_DAR] = random();
+ ucp->uc_link->uc_mcontext.gp_regs[PT_ORIG_R3] = random();
+ ucp->uc_link->uc_mcontext.gp_regs[PT_XER] = random();
+ ucp->uc_link->uc_mcontext.gp_regs[PT_RESULT] = random();
+ ucp->uc_link->uc_mcontext.gp_regs[PT_SOFTE] = random();
+ ucp->uc_link->uc_mcontext.gp_regs[PT_DSCR] = random();
+ ucp->uc_link->uc_mcontext.gp_regs[PT_CTR] = random();
+ ucp->uc_link->uc_mcontext.gp_regs[PT_LNK] = random();
+ ucp->uc_link->uc_mcontext.gp_regs[PT_CCR] = random();
+ ucp->uc_link->uc_mcontext.gp_regs[PT_REGS_COUNT] = random();
+
+ if (args & ARG_MESS_WITH_TM_BEFORE) {
+ if (one_in_chance(2))
+ mess_with_tm();
+ }
+}
+
+static void seg_signal_handler(int signo, siginfo_t *si, void *uc)
+{
+ /* Clear exit for process that segfaults */
+ exit(0);
+}
+
+static void *sigfuz_test(void *thrid)
+{
+ struct sigaction trap_sa, seg_sa;
+ int ret, i = 0;
+ pid_t t;
+
+ tmp_uc = malloc(sizeof(ucontext_t));
+
+ /* Main signal handler */
+ trap_sa.sa_flags = SA_SIGINFO;
+ trap_sa.sa_sigaction = trap_signal_handler;
+
+ /* SIGSEGV signal handler */
+ seg_sa.sa_flags = SA_SIGINFO;
+ seg_sa.sa_sigaction = seg_signal_handler;
+
+ /* The signal handler will enable MSR_TS */
+ sigaction(SIGUSR1, &trap_sa, NULL);
+
+ /* If it does not crash, it will segfault, avoid it to retest */
+ sigaction(SIGSEGV, &seg_sa, NULL);
+
+ while (i < count_max) {
+ t = fork();
+
+ if (t == 0) {
+ /* Once seed per process */
+ srand(time(NULL) + getpid());
+ if (args & ARG_MESS_WITH_TM_AT) {
+ if (one_in_chance(2))
+ mess_with_tm();
+ }
+ raise(SIGUSR1);
+ exit(0);
+ } else {
+ waitpid(t, &ret, 0);
+ }
+ if (!(args & ARG_FOREVER))
+ i++;
+ }
+
+ /* If not freed already, free now */
+ if (tmp_uc) {
+ free(tmp_uc);
+ tmp_uc = NULL;
+ }
+
+ return NULL;
+}
+
+static int signal_fuzzer(void)
+{
+ int t, rc;
+ pthread_t *threads;
+
+ threads = malloc(nthread * sizeof(pthread_t));
+
+ for (t = 0; t < nthread; t++) {
+ rc = pthread_create(&threads[t], NULL, sigfuz_test,
+ (void *)&t);
+ if (rc)
+ perror("Thread creation error\n");
+ }
+
+ for (t = 0; t < nthread; t++) {
+ rc = pthread_join(threads[t], NULL);
+ if (rc)
+ perror("Thread join error\n");
+ }
+
+ free(threads);
+
+ return EXIT_SUCCESS;
+}
+
+static void show_help(char *name)
+{
+ printf("%s: Sigfuzzer for powerpc\n", name);
+ printf("Usage:\n");
+ printf("\t-b\t Mess with TM before raising a SIGUSR1 signal\n");
+ printf("\t-a\t Mess with TM after raising a SIGUSR1 signal\n");
+ printf("\t-m\t Mess with MSR[TS] bits at mcontext\n");
+ printf("\t-x\t Mess with everything above\n");
+ printf("\t-f\t Run forever (Press ^C to Quit)\n");
+ printf("\t-i\t Amount of interactions. (Default = %d)\n", COUNT_MAX);
+ printf("\t-t\t Amount of threads. (Default = %d)\n", THREADS);
+ exit(-1);
+}
+
+int main(int argc, char **argv)
+{
+ int opt;
+
+ while ((opt = getopt(argc, argv, "bamxt:fi:h")) != -1) {
+ if (opt == 'b') {
+ printf("Mess with TM before signal\n");
+ args |= ARG_MESS_WITH_TM_BEFORE;
+ } else if (opt == 'a') {
+ printf("Mess with TM at signal handler\n");
+ args |= ARG_MESS_WITH_TM_AT;
+ } else if (opt == 'm') {
+ printf("Mess with MSR[TS] bits in mcontext\n");
+ args |= ARG_MESS_WITH_MSR_AT;
+ } else if (opt == 'x') {
+ printf("Running with all options enabled\n");
+ args |= ARG_COMPLETE;
+ } else if (opt == 't') {
+ nthread = atoi(optarg);
+ printf("Threads = %d\n", nthread);
+ } else if (opt == 'f') {
+ args |= ARG_FOREVER;
+ printf("Press ^C to stop\n");
+ test_harness_set_timeout(-1);
+ } else if (opt == 'i') {
+ count_max = atoi(optarg);
+ printf("Running for %d interactions\n", count_max);
+ } else if (opt == 'h') {
+ show_help(argv[0]);
+ }
+ }
+
+ /* Default test suite */
+ if (!args)
+ args = ARG_COMPLETE;
+
+ test_harness(signal_fuzzer, "signal_fuzzer");
+}
--
2.19.0
^ permalink raw reply related
* Re: [PATCH 2/4] powerpc/64s: Add slb_full_bitmap rather than hard-coding U32_MAX
From: Segher Boessenkool @ 2019-01-17 16:30 UTC (permalink / raw)
To: Michael Ellerman; +Cc: linuxppc-dev, npiggin
In-Reply-To: <20190117121328.13395-2-mpe@ellerman.id.au>
On Thu, Jan 17, 2019 at 11:13:26PM +1100, Michael Ellerman wrote:
> The recent rewrite of the SLB code into C included the assumption that
> all CPUs we run on have at least 32 SLB entries. This is currently
> true but a bit fragile as the SLB size is actually defined by the
> device tree and so could theoretically change at any time.
It also is guaranteed by the architecture, since at least 2.02, FWIW.
Segher
^ permalink raw reply
* [PATCH] powerpc/cell: Remove duplicate header
From: Sabyasachi Gupta @ 2019-01-17 16:19 UTC (permalink / raw)
To: arnd, benh, paulus, mpe
Cc: brajeswar.linux, linuxppc-dev, jrdr.linux, linux-kernel
Remove linux/syscalls.h which is included more than once
Signed-off-by: Sabyasachi Gupta <sabyasachi.linux@gmail.com>
---
arch/powerpc/platforms/cell/spu_syscalls.c | 1 -
1 file changed, 1 deletion(-)
diff --git a/arch/powerpc/platforms/cell/spu_syscalls.c b/arch/powerpc/platforms/cell/spu_syscalls.c
index 263413a..b95d6af 100644
--- a/arch/powerpc/platforms/cell/spu_syscalls.c
+++ b/arch/powerpc/platforms/cell/spu_syscalls.c
@@ -26,7 +26,6 @@
#include <linux/syscalls.h>
#include <linux/rcupdate.h>
#include <linux/binfmts.h>
-#include <linux/syscalls.h>
#include <asm/spu.h>
--
2.7.4
^ permalink raw reply related
* Re: [PATCH v3 0/4] Add NXP AUDMIX device and machine drivers
From: Rob Herring @ 2019-01-17 16:18 UTC (permalink / raw)
To: Viorel Suman
Cc: Mark Rutland, devicetree@vger.kernel.org,
alsa-devel@alsa-project.org, Timur Tabi, Xiubo Li,
linux-kernel@vger.kernel.org, S.j. Wang,
linuxppc-dev@lists.ozlabs.org, Takashi Iwai, Liam Girdwood,
Nicolin Chen, Cosmin Samoila, Mark Brown, dl-linux-imx,
Viorel Suman, Fabio Estevam, Jaroslav Kysela, Daniel Baluta
In-Reply-To: <1547729177-14317-1-git-send-email-viorel.suman@nxp.com>
On Thu, Jan 17, 2019 at 12:46:25PM +0000, Viorel Suman wrote:
> The patchset adds NXP Audio Mixer (AUDMIX) device and machine
> drivers and related DT bindings documentation.
>
> Changes since V2:
> 1. Moved "dais" node from machine driver DTS node to device driver DTS node
> as suggested by Rob.
That was not what I suggested. You still have a virtual node which looks
to me to be unnecessary.
>
> Changes since V1:
> 1. Original patch split into distinct patches for the device driver and
> DT binding documentation.
> 2. Replaced AMIX with AUDMIX in both code and file names as it looks more
> RM-compliant.
> 3. Removed polarity control from CPU DAI driver as suggested by Nicolin.
> 4. Added machine driver and related DT binding documentation.
>
> Viorel Suman (4):
> ASoC: fsl: Add Audio Mixer CPU DAI driver
> ASoC: add fsl_audmix DT binding documentation
> ASoC: fsl: Add Audio Mixer machine driver
> ASoC: add imx-audmix DT binding documentation
>
> .../devicetree/bindings/sound/fsl,audmix.txt | 50 ++
> .../devicetree/bindings/sound/imx-audmix.txt | 18 +
> sound/soc/fsl/Kconfig | 16 +
> sound/soc/fsl/Makefile | 5 +
> sound/soc/fsl/fsl_audmix.c | 551 +++++++++++++++++++++
> sound/soc/fsl/fsl_audmix.h | 102 ++++
> sound/soc/fsl/imx-audmix.c | 334 +++++++++++++
> 7 files changed, 1076 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/sound/fsl,audmix.txt
> create mode 100644 Documentation/devicetree/bindings/sound/imx-audmix.txt
> create mode 100644 sound/soc/fsl/fsl_audmix.c
> create mode 100644 sound/soc/fsl/fsl_audmix.h
> create mode 100644 sound/soc/fsl/imx-audmix.c
>
> --
> 2.7.4
>
^ permalink raw reply
* [PATCH] powerpc/powernv: Remove duplicate header
From: Sabyasachi Gupta @ 2019-01-17 16:10 UTC (permalink / raw)
To: benh, paulus, mpe, npiggin, msuchanek, haren, oohall, bsingharora
Cc: brajeswar.linux, linuxppc-dev, jrdr.linux, linux-kernel
Remove linux/printk.h which is included more than once.
Signed-off-by: Sabyasachi Gupta <sabyasachi.linux@gmail.com>
---
arch/powerpc/platforms/powernv/opal.c | 1 -
1 file changed, 1 deletion(-)
diff --git a/arch/powerpc/platforms/powernv/opal.c b/arch/powerpc/platforms/powernv/opal.c
index beed86f..802de0d 100644
--- a/arch/powerpc/platforms/powernv/opal.c
+++ b/arch/powerpc/platforms/powernv/opal.c
@@ -26,7 +26,6 @@
#include <linux/memblock.h>
#include <linux/kthread.h>
#include <linux/freezer.h>
-#include <linux/printk.h>
#include <linux/kmsg_dump.h>
#include <linux/console.h>
#include <linux/sched/debug.h>
--
2.7.4
^ permalink raw reply related
* Re: [RESENDING PATCH] powerpc/wii: properly disable use of BATs when requested.
From: Jonathan Neuschäfer @ 2019-01-17 14:55 UTC (permalink / raw)
To: Christophe Leroy
Cc: Jonathan Neuschäfer, stable, linux-kernel, Paul Mackerras,
linuxppc-dev
In-Reply-To: <19fd4dd4-ece2-d508-1ed5-5a9ed2aa84fe@c-s.fr>
[-- Attachment #1: Type: text/plain, Size: 1987 bytes --]
On Thu, Jan 17, 2019 at 11:29:06AM +0100, Christophe Leroy wrote:
[...]
> > > /* MEM2 64MB@0x10000000 */
> > > delta = wii_hole_start + wii_hole_size;
> > > + if (__map_without_bats)
> > > + return delta;
> > > +
> >
> > Nothing is visibly broken without this patch, even with
> > CONFIG_DEBUG_PAGEALLOC (tested on top of v5.0-rc2), but the patch still
> > looks correct.
>
> Obviously, CONFIG_DEBUG_PAGEALLOC cannot work without this patch.
> The purpose of CONFIG_DEBUG_PAGEALLOC is to unmap unused parts of memory so
> that any access to them will pagefault.
>
> As this function inconditionnaly sets a BAT for the second block of RAM, any
> access to free area in the upper block will be granted without a fault.
>
> I think you can test it by doing a kmalloc() then a kfree(), then try to
> read in that area (hopefully kmalloc() allocates memory from the top so it
> should go in the upper block). Maybe there is an LKDTM test for that.
Ah, makes sense, thanks for the explanation.
>
> >
> > I'd prefer the 'if' block to be before the whole delta/size calculation,
> > to make the code slightly more readable because the delta and size
> > calculations stay in one visual block. It doesn't need to happen after
> > delta is calculated.
>
> Euh ... the function has to return 'delta', so if I put the if block before
> the calculation of delta, it means we have to calculate delta twice:
Oh, sorry, I misread the code, but you're completely right (I shouldn't
answer mails while tired).
>
> if (__map_without_bats)
> return wii_hole_start + wii_hole_size;
>
> delta = wii_hole_start + wii_hole_size;
>
> My eyes don't really like it, so if we want to keep delta and size
> calculation together, the 'if' will go after calculation of size.
I agree.
> In anycase, this change is only really for fixing stable releases because
> this function will go away with my other serie.
ACK
Thanks,
Jonathan
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]
^ permalink raw reply
* Re: ppc64le reliable stack unwinder and scheduled tasks
From: Segher Boessenkool @ 2019-01-17 14:52 UTC (permalink / raw)
To: Balbir Singh
Cc: Joe Lawrence, Jiri Kosina, linux-kernel, Torsten Duwe,
live-patching, linuxppc-dev
In-Reply-To: <20190113123356.GA26056@350D>
On Sun, Jan 13, 2019 at 11:33:56PM +1100, Balbir Singh wrote:
> On Sat, Jan 12, 2019 at 02:45:41AM -0600, Segher Boessenkool wrote:
> > On Sat, Jan 12, 2019 at 12:09:14PM +1100, Balbir Singh wrote:
> > > Could you please define interesting frame on top a bit more? Usually
> > > the topmost return address is in LR
> >
> > There is no reliable way (other than DWARF unwind info) to find out where
> > the value of LR at function entry currently lives (if anywhere). It may or
> > may not be still available in LR, it may or may not be saved to the return
> > stack slot. It can also live in some GPR, or in some other stack slot.
> >
> > (The same is true for all other registers).
> >
> > The only thing the ABI guarantees you is that you can find all stack frames
> > via the back chain. If you want more you can use some heuristics and do
> > some heroics (like GDB does), but this is not fully reliable. Using DWARF
> > unwind info is, but that requires big tables.
> >
>
> Thanks, so are you suggesting that a reliable stack is not possible on
> ppc64le? Even with the restricted scope of the kernel?
It depends on what you mean with "reliable stack unwinder". You can unwind
the stack reliably on Power, but you want more, you want to know where some
state local to functions is kept on the stack.
Segher
^ permalink raw reply
page: next (older) | prev (newer) | latest
- recent:[subjects (threaded)|topics (new)|topics (active)]
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox