On Thu, Oct 17, 2019 at 09:16:42AM +0200, David Hildenbrand wrote: > On 17.10.19 01:47, Naoya Horiguchi wrote: > > On Wed, Oct 16, 2019 at 10:57:57AM +0200, David Hildenbrand wrote: > > > On 16.10.19 10:54, Naoya Horiguchi wrote: > > > > On Wed, Oct 16, 2019 at 10:34:52AM +0200, David Hildenbrand wrote: > > > > > On 16.10.19 10:27, Naoya Horiguchi wrote: > > > > > > On Wed, Oct 16, 2019 at 09:56:19AM +0200, David Hildenbrand wrote: > > > > > > > On 16.10.19 09:09, Naoya Horiguchi wrote: > > > > > > > > Hi, > > > > > > > > > > > > > > > > I wrote a simple cleanup for parameter of soft_offline_page(), > > > > > > > > based on thread https://lkml.org/lkml/2019/10/11/57. > > > > > > > > > > > > > > > > I know that we need more cleanup on hwpoison-inject, but I think > > > > > > > > that will be mentioned in re-write patchset Oscar is preparing now. > > > > > > > > So let me shared only this part as a separate one now. > > > > > > ... > > > > > > > > > > > > > > I think you should rebase that patch on linux-next (where the > > > > > > > pfn_to_online_page() check is in place). I assume you'll want to move the > > > > > > > pfn_to_online_page() check into soft_offline_page() then as well? > > > > > > > > > > > > I rebased to next-20191016. And yes, we will move pfn_to_online_page() > > > > > > into soft offline code. It seems that we can also move pfn_valid(), > > > > > > but is simply moving like below good enough for you? > > > > > > > > > > At least I can't am the patch to current next/master (due to > > > > > pfn_to_online_page()). > > > > > > Could also be that my "git am" skills failed as the mail was not a > > > proper patch itself :) > > > > Sorry for the inconvenience, my company email system breaks original > > message by introducing quoted-printable format ('=20' or '=3D'). > > Most mail client usually handles it but git-am doesn't. > > I give up using it and send via smtp.gmail.com. > > > > > > @@ -1877,11 +1877,17 @@ static int soft_offline_free_page(struct page *page) > > > > * This is not a 100% solution for all memory, but tries to be > > > > * ``good enough'' for the majority of memory. > > > > */ > > > > -int soft_offline_page(struct page *page, int flags) > > > > +int soft_offline_page(unsigned long pfn, int flags) > > > > { > > > > int ret; > > > > - unsigned long pfn = page_to_pfn(page); > > > > + struct page *page; > > > > + if (!pfn_valid(pfn)) > > > > + return -ENXIO; > > > > + /* Only online pages can be soft-offlined (esp., not ZONE_DEVICE). */ > > > > + page = pfn_to_online_page(pfn); > > > > + if (!page) > > > > + return -EIO; > > > > if (is_zone_device_page(page)) { > > > > > > -> this is now no longer possible! So you can drop the whole if > > > (is_zone_device....) case > > > > OK, thanks. I updated it. > > > > Thanks, > > Naoya Horiguchi > > --- > > From 5faf227839b578726fe7f5ff414a153abb3b3a31 Mon Sep 17 00:00:00 2001 > > From: Naoya Horiguchi <n-horiguchi@xxxxxxxxxxxxx> > > Date: Thu, 17 Oct 2019 08:40:53 +0900 > > Subject: [PATCH] mm, soft-offline: convert parameter to pfn > > > > Currently soft_offline_page() receives struct page, and its sibling > > memory_failure() receives pfn. This discrepancy looks weird and makes > > precheck on pfn validity tricky. So let's align them. > > > > Signed-off-by: Naoya Horiguchi <n-horiguchi@xxxxxxxxxxxxx> > > --- > > drivers/base/memory.c | 7 +------ > > include/linux/mm.h | 2 +- > > mm/madvise.c | 2 +- > > mm/memory-failure.c | 19 +++++++++---------- > > 4 files changed, 12 insertions(+), 18 deletions(-) > > > > diff --git a/drivers/base/memory.c b/drivers/base/memory.c > > index 55907c27075b..a757d9ed88a7 100644 > > --- a/drivers/base/memory.c > > +++ b/drivers/base/memory.c > > @@ -538,12 +538,7 @@ static ssize_t soft_offline_page_store(struct device *dev, > > if (kstrtoull(buf, 0, &pfn) < 0) > > return -EINVAL; > > pfn >>= PAGE_SHIFT; > > - if (!pfn_valid(pfn)) > > - return -ENXIO; > > - /* Only online pages can be soft-offlined (esp., not ZONE_DEVICE). */ > > - if (!pfn_to_online_page(pfn)) > > - return -EIO; > > - ret = soft_offline_page(pfn_to_page(pfn), 0); > > + ret = soft_offline_page(pfn, 0); > > return ret == 0 ? count : ret; > > } > > diff --git a/include/linux/mm.h b/include/linux/mm.h > > index 44d058723db9..fd360d208346 100644 > > --- a/include/linux/mm.h > > +++ b/include/linux/mm.h > > @@ -2794,7 +2794,7 @@ extern int sysctl_memory_failure_early_kill; > > extern int sysctl_memory_failure_recovery; > > extern void shake_page(struct page *p, int access); > > extern atomic_long_t num_poisoned_pages __read_mostly; > > -extern int soft_offline_page(struct page *page, int flags); > > +extern int soft_offline_page(unsigned long pfn, int flags); > > /* > > diff --git a/mm/madvise.c b/mm/madvise.c > > index 2be9f3fdb05e..99dd06fecfa9 100644 > > --- a/mm/madvise.c > > +++ b/mm/madvise.c > > @@ -887,7 +887,7 @@ static int madvise_inject_error(int behavior, > > pr_info("Soft offlining pfn %#lx at process virtual address %#lx\n", > > pfn, start); > > - ret = soft_offline_page(page, MF_COUNT_INCREASED); > > + ret = soft_offline_page(pfn, MF_COUNT_INCREASED); > > if (ret) > > return ret; > > continue; > > diff --git a/mm/memory-failure.c b/mm/memory-failure.c > > index 05c8c6df25e6..af2712004a4d 100644 > > --- a/mm/memory-failure.c > > +++ b/mm/memory-failure.c > > @@ -1476,7 +1476,7 @@ static void memory_failure_work_func(struct work_struct *work) > > if (!gotten) > > break; > > if (entry.flags & MF_SOFT_OFFLINE) > > - soft_offline_page(pfn_to_page(entry.pfn), entry.flags); > > + soft_offline_page(entry.pfn, entry.flags); > > else > > memory_failure(entry.pfn, entry.flags); > > } > > @@ -1857,7 +1857,7 @@ static int soft_offline_free_page(struct page *page) > > /** > > * soft_offline_page - Soft offline a page. > > - * @page: page to offline > > + * @pfn: pfn to soft-offline > > * @flags: flags. Same as memory_failure(). > > * > > * Returns 0 on success, otherwise negated errno. > > @@ -1877,18 +1877,17 @@ static int soft_offline_free_page(struct page *page) > > * This is not a 100% solution for all memory, but tries to be > > * ``good enough'' for the majority of memory. > > */ > > -int soft_offline_page(struct page *page, int flags) > > +int soft_offline_page(unsigned long pfn, int flags) > > { > > int ret; > > - unsigned long pfn = page_to_pfn(page); > > + struct page *page; > > - if (is_zone_device_page(page)) { > > - pr_debug_ratelimited("soft_offline: %#lx page is device page\n", > > - pfn); > > - if (flags & MF_COUNT_INCREASED) > > - put_page(page); > > + if (!pfn_valid(pfn)) > > + return -ENXIO; > > + /* Only online pages can be soft-offlined (esp., not ZONE_DEVICE). */ > > + page = pfn_to_online_page(pfn); > > + if (!page) > > If you pass in a PFN with MF_COUNT_INCREASED via mm/madvise.c, you would now > no longer do a put_page(page) in case of ZONE_DEVICE (!page = > pfn_to_online_page(pfn);) Yes, right. > > something like this > > page = pfn_to_online_page(pfn); > if (!page) { > /* > * With MF_COUNT_INCREASED, we can use pfn_to_page() directly > * (esp., ZONE_DEVICE). > */ > if (flags & MF_COUNT_INCREASED) > put_page(pfn_to_page(page)); > return -EIO; > } > > For !pfn_valid(pfn), this is not relevant. Actually I guess that !pfn_valid() never happens when called from madvise_inject_error(), because madvise_inject_error() gets pfn via get_user_pages_fast() which only returns valid page for valid pfn. And we plan to remove MF_COUNT_INCREASED by Oscar's re-design work, so I start feeling that this patch should come on top of his tree. Thanks, Naoya Horiguchi
