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()). > > > > > @@ -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). */ > > + if (!pfn_to_online_page(pfn)) > > + return -EIO; > > + page = pfn_to_page(pfn); > > if (is_zone_device_page(page)) { > > pr_debug_ratelimited("soft_offline: %#lx page is device page\n", > > pfn); > > -- > > > > Or we might have an option to do as memory_failure() does like below: > > In contrast to soft offlining, memory failure can deal with devmem. So I > think the above makes sense. OK, so here's the revised one. Thanks, Naoya Horiguchi --- From: Naoya Horiguchi <n-horiguchi@xxxxxxxxxxxxx> Date: Wed, 16 Oct 2019 17:00:33 +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 | 14 ++++++++++---- 4 files changed, 13 insertions(+), 12 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..bdf408d7f65c 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. @@ -1877,11 +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)) { pr_debug_ratelimited("soft_offline: %#lx page is device page\n", pfn); -- 2.17.1
