This is a note to let you know that I've just added the patch titled
kaiser: _pgd_alloc() without __GFP_REPEAT to avoid stalls
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
kaiser-_pgd_alloc-without-__gfp_repeat-to-avoid-stalls.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From foo@baz Wed Jan 3 18:58:12 CET 2018
From: Hugh Dickins <hughd(a)google.com>
Date: Fri, 13 Oct 2017 12:10:00 -0700
Subject: kaiser: _pgd_alloc() without __GFP_REPEAT to avoid stalls
From: Hugh Dickins <hughd(a)google.com>
Synthetic filesystem mempressure testing has shown softlockups, with
hour-long page allocation stalls, and pgd_alloc() trying for order:1
with __GFP_REPEAT in one of the backtraces each time.
That's _pgd_alloc() going for a Kaiser double-pgd, using the __GFP_REPEAT
common to all page table allocations, but actually having no effect on
order:0 (see should_alloc_oom() and should_continue_reclaim() in this
tree, but beware that ports to another tree might behave differently).
Order:1 stack allocation has been working satisfactorily without
__GFP_REPEAT forever, and page table allocation only asks __GFP_REPEAT
for awkward occasions in a long-running process: it's not appropriate
at fork or exec time, and seems to be doing much more harm than good:
getting those contiguous pages under very heavy mempressure can be
hard (though even without it, Kaiser does generate more mempressure).
Mask out that __GFP_REPEAT inside _pgd_alloc(). Why not take it out
of the PGALLOG_GFP altogether, as v4.7 commit a3a9a59d2067 ("x86: get
rid of superfluous __GFP_REPEAT") did? Because I think that might
make a difference to our page table memcg charging, which I'd prefer
not to interfere with at this time.
hughd adds: __alloc_pages_slowpath() in the 4.4.89-stable tree handles
__GFP_REPEAT a little differently than in prod kernel or 3.18.72-stable,
so it may not always be exactly a no-op on order:0 pages, as said above;
but I think still appropriate to omit it from Kaiser or non-Kaiser pgd.
Signed-off-by: Hugh Dickins <hughd(a)google.com>
Acked-by: Jiri Kosina <jkosina(a)suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
arch/x86/mm/pgtable.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
--- a/arch/x86/mm/pgtable.c
+++ b/arch/x86/mm/pgtable.c
@@ -6,7 +6,7 @@
#include <asm/fixmap.h>
#include <asm/mtrr.h>
-#define PGALLOC_GFP GFP_KERNEL | __GFP_NOTRACK | __GFP_REPEAT | __GFP_ZERO
+#define PGALLOC_GFP (GFP_KERNEL | __GFP_NOTRACK | __GFP_REPEAT | __GFP_ZERO)
#ifdef CONFIG_HIGHPTE
#define PGALLOC_USER_GFP __GFP_HIGHMEM
@@ -354,7 +354,9 @@ static inline void _pgd_free(pgd_t *pgd)
static inline pgd_t *_pgd_alloc(void)
{
- return (pgd_t *)__get_free_pages(PGALLOC_GFP, PGD_ALLOCATION_ORDER);
+ /* No __GFP_REPEAT: to avoid page allocation stalls in order-1 case */
+ return (pgd_t *)__get_free_pages(PGALLOC_GFP & ~__GFP_REPEAT,
+ PGD_ALLOCATION_ORDER);
}
static inline void _pgd_free(pgd_t *pgd)
Patches currently in stable-queue which might be from hughd(a)google.com are
queue-4.4/kaiser-vmstat-show-nr_kaisertable-as-nr_overhead.patch
queue-4.4/kaiser-add-nokaiser-boot-option-using-alternative.patch
queue-4.4/kaiser-fix-unlikely-error-in-alloc_ldt_struct.patch
queue-4.4/kaiser-_pgd_alloc-without-__gfp_repeat-to-avoid-stalls.patch
queue-4.4/kaiser-kaiser_flush_tlb_on_return_to_user-check-pcid.patch
queue-4.4/x86-paravirt-dont-patch-flush_tlb_single.patch
queue-4.4/kaiser-merged-update.patch
queue-4.4/kaiser-delete-kaiser_real_switch-option.patch
queue-4.4/kaiser-kaiser_remove_mapping-move-along-the-pgd.patch
queue-4.4/kaiser-fix-perf-crashes.patch
queue-4.4/kaiser-drop-is_atomic-arg-to-kaiser_pagetable_walk.patch
queue-4.4/kaiser-load_new_mm_cr3-let-switch_user_cr3-flush-user.patch
queue-4.4/kaiser-enhanced-by-kernel-and-user-pcids.patch
queue-4.4/kaiser-x86_cr3_pcid_noflush-and-x86_cr3_pcid_user.patch
queue-4.4/kaiser-use-alternative-instead-of-x86_cr3_pcid_noflush.patch
queue-4.4/kaiser-stack-map-page_size-at-thread_size-page_size.patch
queue-4.4/kaiser-name-that-0x1000-kaiser_shadow_pgd_offset.patch
queue-4.4/kaiser-fix-regs-to-do_nmi-ifndef-config_kaiser.patch
queue-4.4/kaiser-do-not-set-_page_nx-on-pgd_none.patch
queue-4.4/kaiser-tidied-up-asm-kaiser.h-somewhat.patch
queue-4.4/kaiser-cleanups-while-trying-for-gold-link.patch
queue-4.4/kaiser-tidied-up-kaiser_add-remove_mapping-slightly.patch
queue-4.4/kaiser-fix-build-and-fixme-in-alloc_ldt_struct.patch
queue-4.4/kaiser-kernel-address-isolation.patch
queue-4.4/kaiser-enomem-if-kaiser_pagetable_walk-null.patch
queue-4.4/kaiser-asm-tlbflush.h-handle-nopge-at-lower-level.patch
queue-4.4/kaiser-paranoid_entry-pass-cr3-need-to-paranoid_exit.patch
queue-4.4/kaiser-kaiser-depends-on-smp.patch
queue-4.4/kaiser-pcid-0-for-kernel-and-128-for-user.patch
On Wed, Jan 03, 2018 at 03:41:21PM +0000, Mark Brown wrote:
> On Wed, Jan 03, 2018 at 04:32:35PM +0100, Arnd Bergmann wrote:
>
> > It might be a problem with different 'make' versions, or something else
> > in the environment that leads to "-Wno-frame-address" not being set
> > on the command line instead.
>
> I'm using "GNU Make 4.1" - this is all just the default Debian stuff,
> I've not customized my x86 host environment.
Make 4.2.1 here with gcc 7.2.1 and I get tons of build warnings on my
3.18.y tree on my laptop, but my build machine running Fedora (make
4.2.1 and gcc 7.2.1) I get no build warnings at all.
I've given up trying to track it down for my laptop, something is
preventing the compiler flag from being added to the gcc command line,
and I don't care anymore...
thanks,
greg k-h
Commit-ID: f24c4d478013d82bd1b943df566fff3561d52864
Gitweb: https://git.kernel.org/tip/f24c4d478013d82bd1b943df566fff3561d52864
Author: Ard Biesheuvel <ard.biesheuvel(a)linaro.org>
AuthorDate: Tue, 2 Jan 2018 17:21:10 +0000
Committer: Ingo Molnar <mingo(a)kernel.org>
CommitDate: Wed, 3 Jan 2018 13:54:31 +0100
efi/capsule-loader: Reinstate virtual capsule mapping
Commit:
82c3768b8d68 ("efi/capsule-loader: Use a cached copy of the capsule header")
... refactored the capsule loading code that maps the capsule header,
to avoid having to map it several times.
However, as it turns out, the vmap() call we ended up removing did not
just map the header, but the entire capsule image, and dropping this
virtual mapping breaks capsules that are processed by the firmware
immediately (i.e., without a reboot).
Unfortunately, that change was part of a larger refactor that allowed
a quirk to be implemented for Quark, which has a non-standard memory
layout for capsules, and we have slightly painted ourselves into a
corner by allowing quirk code to mangle the capsule header and memory
layout.
So we need to fix this without breaking Quark. Fortunately, Quark does
not appear to care about the virtual mapping, and so we can simply
do a partial revert of commit:
2a457fb31df6 ("efi/capsule-loader: Use page addresses rather than struct page pointers")
... and create a vmap() mapping of the entire capsule (including header)
based on the reinstated struct page array, unless running on Quark, in
which case we pass the capsule header copy as before.
Reported-by: Ge Song <ge.song(a)hxt-semitech.com>
Tested-by: Bryan O'Donoghue <pure.logic(a)nexus-software.ie>
Tested-by: Ge Song <ge.song(a)hxt-semitech.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel(a)linaro.org>
Cc: <stable(a)vger.kernel.org>
Cc: Dave Young <dyoung(a)redhat.com>
Cc: Linus Torvalds <torvalds(a)linux-foundation.org>
Cc: Matt Fleming <matt(a)codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz(a)infradead.org>
Cc: Thomas Gleixner <tglx(a)linutronix.de>
Cc: linux-efi(a)vger.kernel.org
Fixes: 82c3768b8d68 ("efi/capsule-loader: Use a cached copy of the capsule header")
Link: http://lkml.kernel.org/r/20180102172110.17018-3-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo(a)kernel.org>
---
arch/x86/platform/efi/quirks.c | 13 +++++++++-
drivers/firmware/efi/capsule-loader.c | 45 ++++++++++++++++++++++++++++-------
include/linux/efi.h | 4 +++-
3 files changed, 52 insertions(+), 10 deletions(-)
diff --git a/arch/x86/platform/efi/quirks.c b/arch/x86/platform/efi/quirks.c
index 8a99a2e..5b513cc 100644
--- a/arch/x86/platform/efi/quirks.c
+++ b/arch/x86/platform/efi/quirks.c
@@ -592,7 +592,18 @@ static int qrk_capsule_setup_info(struct capsule_info *cap_info, void **pkbuff,
/*
* Update the first page pointer to skip over the CSH header.
*/
- cap_info->pages[0] += csh->headersize;
+ cap_info->phys[0] += csh->headersize;
+
+ /*
+ * cap_info->capsule should point at a virtual mapping of the entire
+ * capsule, starting at the capsule header. Our image has the Quark
+ * security header prepended, so we cannot rely on the default vmap()
+ * mapping created by the generic capsule code.
+ * Given that the Quark firmware does not appear to care about the
+ * virtual mapping, let's just point cap_info->capsule at our copy
+ * of the capsule header.
+ */
+ cap_info->capsule = &cap_info->header;
return 1;
}
diff --git a/drivers/firmware/efi/capsule-loader.c b/drivers/firmware/efi/capsule-loader.c
index ec8ac5c..055e2e8 100644
--- a/drivers/firmware/efi/capsule-loader.c
+++ b/drivers/firmware/efi/capsule-loader.c
@@ -20,10 +20,6 @@
#define NO_FURTHER_WRITE_ACTION -1
-#ifndef phys_to_page
-#define phys_to_page(x) pfn_to_page((x) >> PAGE_SHIFT)
-#endif
-
/**
* efi_free_all_buff_pages - free all previous allocated buffer pages
* @cap_info: pointer to current instance of capsule_info structure
@@ -35,7 +31,7 @@
static void efi_free_all_buff_pages(struct capsule_info *cap_info)
{
while (cap_info->index > 0)
- __free_page(phys_to_page(cap_info->pages[--cap_info->index]));
+ __free_page(cap_info->pages[--cap_info->index]);
cap_info->index = NO_FURTHER_WRITE_ACTION;
}
@@ -71,6 +67,14 @@ int __efi_capsule_setup_info(struct capsule_info *cap_info)
cap_info->pages = temp_page;
+ temp_page = krealloc(cap_info->phys,
+ pages_needed * sizeof(phys_addr_t *),
+ GFP_KERNEL | __GFP_ZERO);
+ if (!temp_page)
+ return -ENOMEM;
+
+ cap_info->phys = temp_page;
+
return 0;
}
@@ -105,9 +109,24 @@ int __weak efi_capsule_setup_info(struct capsule_info *cap_info, void *kbuff,
**/
static ssize_t efi_capsule_submit_update(struct capsule_info *cap_info)
{
+ bool do_vunmap = false;
int ret;
- ret = efi_capsule_update(&cap_info->header, cap_info->pages);
+ /*
+ * cap_info->capsule may have been assigned already by a quirk
+ * handler, so only overwrite it if it is NULL
+ */
+ if (!cap_info->capsule) {
+ cap_info->capsule = vmap(cap_info->pages, cap_info->index,
+ VM_MAP, PAGE_KERNEL);
+ if (!cap_info->capsule)
+ return -ENOMEM;
+ do_vunmap = true;
+ }
+
+ ret = efi_capsule_update(cap_info->capsule, cap_info->phys);
+ if (do_vunmap)
+ vunmap(cap_info->capsule);
if (ret) {
pr_err("capsule update failed\n");
return ret;
@@ -165,10 +184,12 @@ static ssize_t efi_capsule_write(struct file *file, const char __user *buff,
goto failed;
}
- cap_info->pages[cap_info->index++] = page_to_phys(page);
+ cap_info->pages[cap_info->index] = page;
+ cap_info->phys[cap_info->index] = page_to_phys(page);
cap_info->page_bytes_remain = PAGE_SIZE;
+ cap_info->index++;
} else {
- page = phys_to_page(cap_info->pages[cap_info->index - 1]);
+ page = cap_info->pages[cap_info->index - 1];
}
kbuff = kmap(page);
@@ -252,6 +273,7 @@ static int efi_capsule_release(struct inode *inode, struct file *file)
struct capsule_info *cap_info = file->private_data;
kfree(cap_info->pages);
+ kfree(cap_info->phys);
kfree(file->private_data);
file->private_data = NULL;
return 0;
@@ -281,6 +303,13 @@ static int efi_capsule_open(struct inode *inode, struct file *file)
return -ENOMEM;
}
+ cap_info->phys = kzalloc(sizeof(void *), GFP_KERNEL);
+ if (!cap_info->phys) {
+ kfree(cap_info->pages);
+ kfree(cap_info);
+ return -ENOMEM;
+ }
+
file->private_data = cap_info;
return 0;
diff --git a/include/linux/efi.h b/include/linux/efi.h
index d813f7b..29fdf80 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -140,11 +140,13 @@ struct efi_boot_memmap {
struct capsule_info {
efi_capsule_header_t header;
+ efi_capsule_header_t *capsule;
int reset_type;
long index;
size_t count;
size_t total_size;
- phys_addr_t *pages;
+ struct page **pages;
+ phys_addr_t *phys;
size_t page_bytes_remain;
};
The patch
ASoC: skl: Fix kernel warning due to zero NHTL entry
has been applied to the asoc tree at
https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git
All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.
You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.
If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.
Please add any relevant lists and maintainers to the CCs when replying
to this mail.
Thanks,
Mark
>From 20a1ea2222e7cbf96e9bf8579362e971491e6aea Mon Sep 17 00:00:00 2001
From: Takashi Iwai <tiwai(a)suse.de>
Date: Wed, 3 Jan 2018 16:38:46 +0100
Subject: [PATCH] ASoC: skl: Fix kernel warning due to zero NHTL entry
I got the following kernel warning when loading snd-soc-skl module on
Dell Latitude 7270 laptop:
memremap attempted on mixed range 0x0000000000000000 size: 0x0
WARNING: CPU: 0 PID: 484 at kernel/memremap.c:98 memremap+0x8a/0x180
Call Trace:
skl_nhlt_init+0x82/0xf0 [snd_soc_skl]
skl_probe+0x2ee/0x7c0 [snd_soc_skl]
....
It seems that the machine doesn't support the SKL DSP gives the empty
NHLT entry, and it triggers the warning. For avoiding it, let do the
zero check before calling memremap().
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai(a)suse.de>
Signed-off-by: Mark Brown <broonie(a)kernel.org>
---
sound/soc/intel/skylake/skl-nhlt.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/sound/soc/intel/skylake/skl-nhlt.c b/sound/soc/intel/skylake/skl-nhlt.c
index d14c50a60289..1ce414d86d8a 100644
--- a/sound/soc/intel/skylake/skl-nhlt.c
+++ b/sound/soc/intel/skylake/skl-nhlt.c
@@ -43,7 +43,8 @@ struct nhlt_acpi_table *skl_nhlt_init(struct device *dev)
obj = acpi_evaluate_dsm(handle, &osc_guid, 1, 1, NULL);
if (obj && obj->type == ACPI_TYPE_BUFFER) {
nhlt_ptr = (struct nhlt_resource_desc *)obj->buffer.pointer;
- nhlt_table = (struct nhlt_acpi_table *)
+ if (nhlt_ptr->length)
+ nhlt_table = (struct nhlt_acpi_table *)
memremap(nhlt_ptr->min_addr, nhlt_ptr->length,
MEMREMAP_WB);
ACPI_FREE(obj);
--
2.15.1
On Wed, Jan 3, 2018 at 3:59 PM, Mark Brown <broonie(a)kernel.org> wrote:
> On Wed, Jan 03, 2018 at 03:52:12PM +0100, Arnd Bergmann wrote:
>
>> Greg and Mark, which x86-64 compiler versions do you use?
>
> gcc (Debian 6.3.0-18) 6.3.0 20170516
I installed that version here, same as my other gcc-6 versions, the
"-Wno-frame-address" option gets set and interpreted correctly:
$ git checkout v3.18.91 ; touch kernel/sched/core.c ; make V=1
defconfig kernel/sched/core.o CC=gcc-6 2>&1 | tail
...
gcc-6 -Wp,-MD,kernel/sched/.core.o.d -nostdinc -isystem
/usr/lib/gcc/x86_64-linux-gnu/6/include -I./arch/x86/include
-Iarch/x86/include/generated -Iinclude -I./arch/x86/include/uapi
-Iarch/x86/include/generated/uapi -I./include/uapi
-Iinclude/generated/uapi -include ./include/linux/kconfig.h
-D__KERNEL__ -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs
-fno-strict-aliasing -fno-common -Werror-implicit-function-declaration
-Wno-format-security -std=gnu89 -m64 -mno-80387 -mno-fp-ret-in-387
-mtune=generic -mno-red-zone -mcmodel=kernel -funit-at-a-time
-maccumulate-outgoing-args -DCONFIG_AS_CFI=1
-DCONFIG_AS_CFI_SIGNAL_FRAME=1 -DCONFIG_AS_CFI_SECTIONS=1
-DCONFIG_AS_FXSAVEQ=1 -DCONFIG_AS_CRC32=1 -DCONFIG_AS_AVX=1
-DCONFIG_AS_AVX2=1 -pipe -Wno-sign-compare
-fno-asynchronous-unwind-tables -mno-sse -mno-mmx -mno-sse2 -mno-3dnow
-mno-avx -fno-delete-null-pointer-checks -Wno-frame-address -fno-PIE
-O2 --param=allow-store-data-races=0 -Wframe-larger-than=2048
-fno-stack-protector -Wno-unused-but-set-variable
-Wno-unused-const-variable -fno-omit-frame-pointer
-fno-optimize-sibling-calls -fno-var-tracking-assignments
-Wdeclaration-after-statement -Wno-pointer-sign -fno-strict-overflow
-fno-stack-check -fconserve-stack -Werror=implicit-int
-Werror=strict-prototypes -Werror=date-time -DCC_HAVE_ASM_GOTO
-D"KBUILD_STR(s)=#s" -D"KBUILD_BASENAME=KBUILD_STR(core)"
-D"KBUILD_MODNAME=KBUILD_STR(core)" -c -o kernel/sched/core.o
kernel/sched/core.c
It might be a problem with different 'make' versions, or something else
in the environment that leads to "-Wno-frame-address" not being set
on the command line instead.
Arnd
This is a note to let you know that I've just added the patch titled
x86/boot: Add early cmdline parsing for options with arguments
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
x86-boot-add-early-cmdline-parsing-for-options-with-arguments.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From e505371dd83963caae1a37ead9524e8d997341be Mon Sep 17 00:00:00 2001
From: Tom Lendacky <thomas.lendacky(a)amd.com>
Date: Mon, 17 Jul 2017 16:10:33 -0500
Subject: x86/boot: Add early cmdline parsing for options with arguments
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
From: Tom Lendacky <thomas.lendacky(a)amd.com>
commit e505371dd83963caae1a37ead9524e8d997341be upstream.
Add a cmdline_find_option() function to look for cmdline options that
take arguments. The argument is returned in a supplied buffer and the
argument length (regardless of whether it fits in the supplied buffer)
is returned, with -1 indicating not found.
Signed-off-by: Tom Lendacky <thomas.lendacky(a)amd.com>
Reviewed-by: Thomas Gleixner <tglx(a)linutronix.de>
Cc: Alexander Potapenko <glider(a)google.com>
Cc: Andrey Ryabinin <aryabinin(a)virtuozzo.com>
Cc: Andy Lutomirski <luto(a)kernel.org>
Cc: Arnd Bergmann <arnd(a)arndb.de>
Cc: Borislav Petkov <bp(a)alien8.de>
Cc: Brijesh Singh <brijesh.singh(a)amd.com>
Cc: Dave Young <dyoung(a)redhat.com>
Cc: Dmitry Vyukov <dvyukov(a)google.com>
Cc: Jonathan Corbet <corbet(a)lwn.net>
Cc: Konrad Rzeszutek Wilk <konrad.wilk(a)oracle.com>
Cc: Larry Woodman <lwoodman(a)redhat.com>
Cc: Linus Torvalds <torvalds(a)linux-foundation.org>
Cc: Matt Fleming <matt(a)codeblueprint.co.uk>
Cc: Michael S. Tsirkin <mst(a)redhat.com>
Cc: Paolo Bonzini <pbonzini(a)redhat.com>
Cc: Peter Zijlstra <peterz(a)infradead.org>
Cc: Radim Krčmář <rkrcmar(a)redhat.com>
Cc: Rik van Riel <riel(a)redhat.com>
Cc: Toshimitsu Kani <toshi.kani(a)hpe.com>
Cc: kasan-dev(a)googlegroups.com
Cc: kvm(a)vger.kernel.org
Cc: linux-arch(a)vger.kernel.org
Cc: linux-doc(a)vger.kernel.org
Cc: linux-efi(a)vger.kernel.org
Cc: linux-mm(a)kvack.org
Link: http://lkml.kernel.org/r/36b5f97492a9745dce27682305f990fc20e5cf8a.150031921…
Signed-off-by: Ingo Molnar <mingo(a)kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
arch/x86/include/asm/cmdline.h | 2
arch/x86/lib/cmdline.c | 105 +++++++++++++++++++++++++++++++++++++++++
2 files changed, 107 insertions(+)
--- a/arch/x86/include/asm/cmdline.h
+++ b/arch/x86/include/asm/cmdline.h
@@ -2,5 +2,7 @@
#define _ASM_X86_CMDLINE_H
int cmdline_find_option_bool(const char *cmdline_ptr, const char *option);
+int cmdline_find_option(const char *cmdline_ptr, const char *option,
+ char *buffer, int bufsize);
#endif /* _ASM_X86_CMDLINE_H */
--- a/arch/x86/lib/cmdline.c
+++ b/arch/x86/lib/cmdline.c
@@ -82,3 +82,108 @@ int cmdline_find_option_bool(const char
return 0; /* Buffer overrun */
}
+
+/*
+ * Find a non-boolean option (i.e. option=argument). In accordance with
+ * standard Linux practice, if this option is repeated, this returns the
+ * last instance on the command line.
+ *
+ * @cmdline: the cmdline string
+ * @max_cmdline_size: the maximum size of cmdline
+ * @option: option string to look for
+ * @buffer: memory buffer to return the option argument
+ * @bufsize: size of the supplied memory buffer
+ *
+ * Returns the length of the argument (regardless of if it was
+ * truncated to fit in the buffer), or -1 on not found.
+ */
+static int
+__cmdline_find_option(const char *cmdline, int max_cmdline_size,
+ const char *option, char *buffer, int bufsize)
+{
+ char c;
+ int pos = 0, len = -1;
+ const char *opptr = NULL;
+ char *bufptr = buffer;
+ enum {
+ st_wordstart = 0, /* Start of word/after whitespace */
+ st_wordcmp, /* Comparing this word */
+ st_wordskip, /* Miscompare, skip */
+ st_bufcpy, /* Copying this to buffer */
+ } state = st_wordstart;
+
+ if (!cmdline)
+ return -1; /* No command line */
+
+ /*
+ * This 'pos' check ensures we do not overrun
+ * a non-NULL-terminated 'cmdline'
+ */
+ while (pos++ < max_cmdline_size) {
+ c = *(char *)cmdline++;
+ if (!c)
+ break;
+
+ switch (state) {
+ case st_wordstart:
+ if (myisspace(c))
+ break;
+
+ state = st_wordcmp;
+ opptr = option;
+ /* fall through */
+
+ case st_wordcmp:
+ if ((c == '=') && !*opptr) {
+ /*
+ * We matched all the way to the end of the
+ * option we were looking for, prepare to
+ * copy the argument.
+ */
+ len = 0;
+ bufptr = buffer;
+ state = st_bufcpy;
+ break;
+ } else if (c == *opptr++) {
+ /*
+ * We are currently matching, so continue
+ * to the next character on the cmdline.
+ */
+ break;
+ }
+ state = st_wordskip;
+ /* fall through */
+
+ case st_wordskip:
+ if (myisspace(c))
+ state = st_wordstart;
+ break;
+
+ case st_bufcpy:
+ if (myisspace(c)) {
+ state = st_wordstart;
+ } else {
+ /*
+ * Increment len, but don't overrun the
+ * supplied buffer and leave room for the
+ * NULL terminator.
+ */
+ if (++len < bufsize)
+ *bufptr++ = c;
+ }
+ break;
+ }
+ }
+
+ if (bufsize)
+ *bufptr = '\0';
+
+ return len;
+}
+
+int cmdline_find_option(const char *cmdline, const char *option, char *buffer,
+ int bufsize)
+{
+ return __cmdline_find_option(cmdline, COMMAND_LINE_SIZE, option,
+ buffer, bufsize);
+}
Patches currently in stable-queue which might be from thomas.lendacky(a)amd.com are
queue-4.4/x86-boot-add-early-cmdline-parsing-for-options-with-arguments.patch
This is a note to let you know that I've just added the patch titled
x86/boot: Add early cmdline parsing for options with arguments
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
x86-boot-add-early-cmdline-parsing-for-options-with-arguments.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From e505371dd83963caae1a37ead9524e8d997341be Mon Sep 17 00:00:00 2001
From: Tom Lendacky <thomas.lendacky(a)amd.com>
Date: Mon, 17 Jul 2017 16:10:33 -0500
Subject: x86/boot: Add early cmdline parsing for options with arguments
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
From: Tom Lendacky <thomas.lendacky(a)amd.com>
commit e505371dd83963caae1a37ead9524e8d997341be upstream.
Add a cmdline_find_option() function to look for cmdline options that
take arguments. The argument is returned in a supplied buffer and the
argument length (regardless of whether it fits in the supplied buffer)
is returned, with -1 indicating not found.
Signed-off-by: Tom Lendacky <thomas.lendacky(a)amd.com>
Reviewed-by: Thomas Gleixner <tglx(a)linutronix.de>
Cc: Alexander Potapenko <glider(a)google.com>
Cc: Andrey Ryabinin <aryabinin(a)virtuozzo.com>
Cc: Andy Lutomirski <luto(a)kernel.org>
Cc: Arnd Bergmann <arnd(a)arndb.de>
Cc: Borislav Petkov <bp(a)alien8.de>
Cc: Brijesh Singh <brijesh.singh(a)amd.com>
Cc: Dave Young <dyoung(a)redhat.com>
Cc: Dmitry Vyukov <dvyukov(a)google.com>
Cc: Jonathan Corbet <corbet(a)lwn.net>
Cc: Konrad Rzeszutek Wilk <konrad.wilk(a)oracle.com>
Cc: Larry Woodman <lwoodman(a)redhat.com>
Cc: Linus Torvalds <torvalds(a)linux-foundation.org>
Cc: Matt Fleming <matt(a)codeblueprint.co.uk>
Cc: Michael S. Tsirkin <mst(a)redhat.com>
Cc: Paolo Bonzini <pbonzini(a)redhat.com>
Cc: Peter Zijlstra <peterz(a)infradead.org>
Cc: Radim Krčmář <rkrcmar(a)redhat.com>
Cc: Rik van Riel <riel(a)redhat.com>
Cc: Toshimitsu Kani <toshi.kani(a)hpe.com>
Cc: kasan-dev(a)googlegroups.com
Cc: kvm(a)vger.kernel.org
Cc: linux-arch(a)vger.kernel.org
Cc: linux-doc(a)vger.kernel.org
Cc: linux-efi(a)vger.kernel.org
Cc: linux-mm(a)kvack.org
Link: http://lkml.kernel.org/r/36b5f97492a9745dce27682305f990fc20e5cf8a.150031921…
Signed-off-by: Ingo Molnar <mingo(a)kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
arch/x86/include/asm/cmdline.h | 2
arch/x86/lib/cmdline.c | 105 +++++++++++++++++++++++++++++++++++++++++
2 files changed, 107 insertions(+)
--- a/arch/x86/include/asm/cmdline.h
+++ b/arch/x86/include/asm/cmdline.h
@@ -2,5 +2,7 @@
#define _ASM_X86_CMDLINE_H
int cmdline_find_option_bool(const char *cmdline_ptr, const char *option);
+int cmdline_find_option(const char *cmdline_ptr, const char *option,
+ char *buffer, int bufsize);
#endif /* _ASM_X86_CMDLINE_H */
--- a/arch/x86/lib/cmdline.c
+++ b/arch/x86/lib/cmdline.c
@@ -104,7 +104,112 @@ __cmdline_find_option_bool(const char *c
return 0; /* Buffer overrun */
}
+/*
+ * Find a non-boolean option (i.e. option=argument). In accordance with
+ * standard Linux practice, if this option is repeated, this returns the
+ * last instance on the command line.
+ *
+ * @cmdline: the cmdline string
+ * @max_cmdline_size: the maximum size of cmdline
+ * @option: option string to look for
+ * @buffer: memory buffer to return the option argument
+ * @bufsize: size of the supplied memory buffer
+ *
+ * Returns the length of the argument (regardless of if it was
+ * truncated to fit in the buffer), or -1 on not found.
+ */
+static int
+__cmdline_find_option(const char *cmdline, int max_cmdline_size,
+ const char *option, char *buffer, int bufsize)
+{
+ char c;
+ int pos = 0, len = -1;
+ const char *opptr = NULL;
+ char *bufptr = buffer;
+ enum {
+ st_wordstart = 0, /* Start of word/after whitespace */
+ st_wordcmp, /* Comparing this word */
+ st_wordskip, /* Miscompare, skip */
+ st_bufcpy, /* Copying this to buffer */
+ } state = st_wordstart;
+
+ if (!cmdline)
+ return -1; /* No command line */
+
+ /*
+ * This 'pos' check ensures we do not overrun
+ * a non-NULL-terminated 'cmdline'
+ */
+ while (pos++ < max_cmdline_size) {
+ c = *(char *)cmdline++;
+ if (!c)
+ break;
+
+ switch (state) {
+ case st_wordstart:
+ if (myisspace(c))
+ break;
+
+ state = st_wordcmp;
+ opptr = option;
+ /* fall through */
+
+ case st_wordcmp:
+ if ((c == '=') && !*opptr) {
+ /*
+ * We matched all the way to the end of the
+ * option we were looking for, prepare to
+ * copy the argument.
+ */
+ len = 0;
+ bufptr = buffer;
+ state = st_bufcpy;
+ break;
+ } else if (c == *opptr++) {
+ /*
+ * We are currently matching, so continue
+ * to the next character on the cmdline.
+ */
+ break;
+ }
+ state = st_wordskip;
+ /* fall through */
+
+ case st_wordskip:
+ if (myisspace(c))
+ state = st_wordstart;
+ break;
+
+ case st_bufcpy:
+ if (myisspace(c)) {
+ state = st_wordstart;
+ } else {
+ /*
+ * Increment len, but don't overrun the
+ * supplied buffer and leave room for the
+ * NULL terminator.
+ */
+ if (++len < bufsize)
+ *bufptr++ = c;
+ }
+ break;
+ }
+ }
+
+ if (bufsize)
+ *bufptr = '\0';
+
+ return len;
+}
+
int cmdline_find_option_bool(const char *cmdline, const char *option)
{
return __cmdline_find_option_bool(cmdline, COMMAND_LINE_SIZE, option);
}
+
+int cmdline_find_option(const char *cmdline, const char *option, char *buffer,
+ int bufsize)
+{
+ return __cmdline_find_option(cmdline, COMMAND_LINE_SIZE, option,
+ buffer, bufsize);
+}
Patches currently in stable-queue which might be from thomas.lendacky(a)amd.com are
queue-4.9/x86-boot-add-early-cmdline-parsing-for-options-with-arguments.patch