| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <20180714015223.GA2745@dhcp-128-65.nay.redhat.com>
Date: Sat, 14 Jul 2018 09:52:23 +0800
From: Dave Young <dyoung@...hat.com>
To: AKASHI Takahiro <takahiro.akashi@...aro.org>
Cc: catalin.marinas@....com, will.deacon@....com, dhowells@...hat.com,
vgoyal@...hat.com, herbert@...dor.apana.org.au,
davem@...emloft.net, bhe@...hat.com, arnd@...db.de,
ard.biesheuvel@...aro.org, james.morse@....com,
bhsharma@...hat.com, kexec@...ts.infradead.org,
linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org,
"Eric W. Biederman" <ebiederm@...ssion.com>
Subject: Re: [PATCH v11 03/15] powerpc, kexec_file: factor out memblock-based
arch_kexec_walk_mem()
On 07/11/18 at 04:41pm, AKASHI Takahiro wrote:
> Memblock list is another source for usable system memory layout.
> So powerpc's arch_kexec_walk_mem() is moved to kexec_file.c so that
> other memblock-based architectures, particularly arm64, can also utilise
> it. A moved function is now renamed to kexec_walk_memblock() and merged
> into the existing arch_kexec_walk_mem() for general use, either resource
> list or memblock list.
>
> A consequent function will not work for kdump with memblock list, but
> this will be fixed in the next patch.
>
> Signed-off-by: AKASHI Takahiro <takahiro.akashi@...aro.org>
> Cc: "Eric W. Biederman" <ebiederm@...ssion.com>
> Cc: Dave Young <dyoung@...hat.com>
> Cc: Vivek Goyal <vgoyal@...hat.com>
> Cc: Baoquan He <bhe@...hat.com>
> Acked-by: James Morse <james.morse@....com>
> ---
> arch/powerpc/kernel/machine_kexec_file_64.c | 54 ---------------------
> kernel/kexec_file.c | 54 +++++++++++++++++++++
> 2 files changed, 54 insertions(+), 54 deletions(-)
>
> diff --git a/arch/powerpc/kernel/machine_kexec_file_64.c b/arch/powerpc/kernel/machine_kexec_file_64.c
> index 0bd23dc789a4..5357b09902c5 100644
> --- a/arch/powerpc/kernel/machine_kexec_file_64.c
> +++ b/arch/powerpc/kernel/machine_kexec_file_64.c
> @@ -24,7 +24,6 @@
>
> #include <linux/slab.h>
> #include <linux/kexec.h>
> -#include <linux/memblock.h>
> #include <linux/of_fdt.h>
> #include <linux/libfdt.h>
> #include <asm/ima.h>
> @@ -46,59 +45,6 @@ int arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
> return kexec_image_probe_default(image, buf, buf_len);
> }
>
> -/**
> - * arch_kexec_walk_mem - call func(data) for each unreserved memory block
> - * @kbuf: Context info for the search. Also passed to @func.
> - * @func: Function to call for each memory block.
> - *
> - * This function is used by kexec_add_buffer and kexec_locate_mem_hole
> - * to find unreserved memory to load kexec segments into.
> - *
> - * Return: The memory walk will stop when func returns a non-zero value
> - * and that value will be returned. If all free regions are visited without
> - * func returning non-zero, then zero will be returned.
> - */
> -int arch_kexec_walk_mem(struct kexec_buf *kbuf,
> - int (*func)(struct resource *, void *))
> -{
> - int ret = 0;
> - u64 i;
> - phys_addr_t mstart, mend;
> - struct resource res = { };
> -
> - if (kbuf->top_down) {
> - for_each_free_mem_range_reverse(i, NUMA_NO_NODE, 0,
> - &mstart, &mend, NULL) {
> - /*
> - * In memblock, end points to the first byte after the
> - * range while in kexec, end points to the last byte
> - * in the range.
> - */
> - res.start = mstart;
> - res.end = mend - 1;
> - ret = func(&res, kbuf);
> - if (ret)
> - break;
> - }
> - } else {
> - for_each_free_mem_range(i, NUMA_NO_NODE, 0, &mstart, &mend,
> - NULL) {
> - /*
> - * In memblock, end points to the first byte after the
> - * range while in kexec, end points to the last byte
> - * in the range.
> - */
> - res.start = mstart;
> - res.end = mend - 1;
> - ret = func(&res, kbuf);
> - if (ret)
> - break;
> - }
> - }
> -
> - return ret;
> -}
> -
> /**
> * setup_purgatory - initialize the purgatory's global variables
> * @image: kexec image.
> diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c
> index 63c7ce1c0c3e..b088324fb3ad 100644
> --- a/kernel/kexec_file.c
> +++ b/kernel/kexec_file.c
> @@ -16,6 +16,7 @@
> #include <linux/file.h>
> #include <linux/slab.h>
> #include <linux/kexec.h>
> +#include <linux/memblock.h>
> #include <linux/mutex.h>
> #include <linux/list.h>
> #include <linux/fs.h>
> @@ -501,6 +502,55 @@ static int locate_mem_hole_callback(struct resource *res, void *arg)
> return locate_mem_hole_bottom_up(start, end, kbuf);
> }
>
> +#if defined(CONFIG_HAVE_MEMBLOCK) && !defined(CONFIG_ARCH_DISCARD_MEMBLOCK)
> +static int kexec_walk_memblock(struct kexec_buf *kbuf,
> + int (*func)(struct resource *, void *))
> +{
> + int ret = 0;
> + u64 i;
> + phys_addr_t mstart, mend;
> + struct resource res = { };
> +
> + if (kbuf->top_down) {
> + for_each_free_mem_range_reverse(i, NUMA_NO_NODE, 0,
> + &mstart, &mend, NULL) {
> + /*
> + * In memblock, end points to the first byte after the
> + * range while in kexec, end points to the last byte
> + * in the range.
> + */
> + res.start = mstart;
> + res.end = mend - 1;
> + ret = func(&res, kbuf);
> + if (ret)
> + break;
> + }
> + } else {
> + for_each_free_mem_range(i, NUMA_NO_NODE, 0, &mstart, &mend,
> + NULL) {
> + /*
> + * In memblock, end points to the first byte after the
> + * range while in kexec, end points to the last byte
> + * in the range.
> + */
> + res.start = mstart;
> + res.end = mend - 1;
> + ret = func(&res, kbuf);
> + if (ret)
> + break;
> + }
> + }
> +
> + return ret;
> +}
> +#else
> +static int kexec_walk_memblock(struct kexec_buf *kbuf,
> + int (*func)(struct resource *, void *))
> +{
> + return 0;
> +}
> +#endif
> +
> /**
> * arch_kexec_walk_mem - call func(data) on free memory regions
> * @kbuf: Context info for the search. Also passed to @func.
> @@ -513,6 +563,10 @@ static int locate_mem_hole_callback(struct resource *res, void *arg)
> int __weak arch_kexec_walk_mem(struct kexec_buf *kbuf,
> int (*func)(struct resource *, void *))
> {
> + if (IS_ENABLED(CONFIG_HAVE_MEMBLOCK) &&
> + !IS_ENABLED(CONFIG_ARCH_DISCARD_MEMBLOCK))
> + return kexec_walk_memblock(kbuf, func);
AKASHI, I'm not sure if this works on all arches, for example I chekced
the .config on my Nokia N900 kernel tree, there is HAVE_MEMBLOCK=y and
no CONFIG_ARCH_DISCARD_MEMBLOCK, in 32bit arm code no
arch_kexec_walk_mem()
> +
> if (kbuf->image->type == KEXEC_TYPE_CRASH)
> return walk_iomem_res_desc(crashk_res.desc,
> IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY,
> --
> 2.17.0
>
Thanks
Dave
Powered by blists - more mailing lists