From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ozlabs.org (ozlabs.org [IPv6:2401:3900:2:1::2]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3wK9554ywbzDqCL for ; Fri, 5 May 2017 21:43:21 +1000 (AEST) Received: from ozlabs.org (ozlabs.org [103.22.144.67]) by bilbo.ozlabs.org (Postfix) with ESMTP id 3wK9553yqxz8tdd for ; Fri, 5 May 2017 21:43:21 +1000 (AEST) Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 3wK95509lNz9s7s for ; Fri, 5 May 2017 21:43:21 +1000 (AEST) Date: Fri, 5 May 2017 07:43:18 -0400 (EDT) From: Pingfan Liu To: Hari Bathini Cc: Michael Ellerman , linuxppc-dev , Mahesh J Salgaonkar Message-ID: <935304973.5269011.1493984598730.JavaMail.zimbra@redhat.com> In-Reply-To: <149392044508.10802.11008391107873058533.stgit@hbathini.in.ibm.com> References: <149392041651.10802.10097444663269312695.stgit@hbathini.in.ibm.com> <149392044508.10802.11008391107873058533.stgit@hbathini.in.ibm.com> Subject: Re: [PATCH 2/2] powerpc/fadump: avoid holes in boot memory area when fadump is registered MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , ----- Original Message ----- > From: "Hari Bathini" > To: "Michael Ellerman" > Cc: "linuxppc-dev" , "Pingfan Liu" , "Mahesh J Salgaonkar" > > Sent: Friday, May 5, 2017 1:54:05 AM > Subject: [PATCH 2/2] powerpc/fadump: avoid holes in boot memory area when fadump is registered > > To register fadump, boot memory area - the size of low memory chunk that > is required for a kernel to boot successfully when booted with restricted > memory, is assumed to have no holes. But this memory area is currently The continuous is required by fadump code, not by the firmware itself, right? Thanks and regards, Pingfan > not protected from hot-remove operations. So, fadump could fail to > re-register after a memory hot-remove operation, if memory is removed > from boot memory area. To avoid this, ensure that memory from boot > memory area is not hot-removed when fadump is registered. > > Signed-off-by: Hari Bathini > --- > arch/powerpc/include/asm/fadump.h | 1 + > arch/powerpc/kernel/fadump.c | 12 ++++++++++++ > arch/powerpc/platforms/pseries/hotplug-memory.c | 7 +++++++ > 3 files changed, 20 insertions(+) > > diff --git a/arch/powerpc/include/asm/fadump.h > b/arch/powerpc/include/asm/fadump.h > index 0031806..609fccc 100644 > --- a/arch/powerpc/include/asm/fadump.h > +++ b/arch/powerpc/include/asm/fadump.h > @@ -198,6 +198,7 @@ struct fad_crash_memory_ranges { > unsigned long long size; > }; > > +extern int is_fadump_boot_memory_area(u64 addr, ulong size); > extern int early_init_dt_scan_fw_dump(unsigned long node, > const char *uname, int depth, void *data); > extern int fadump_reserve_mem(void); > diff --git a/arch/powerpc/kernel/fadump.c b/arch/powerpc/kernel/fadump.c > index 03563c6..ea7dfdc 100644 > --- a/arch/powerpc/kernel/fadump.c > +++ b/arch/powerpc/kernel/fadump.c > @@ -114,6 +114,18 @@ int __init early_init_dt_scan_fw_dump(unsigned long > node, > return 1; > } > > +/* > + * If fadump is registered, check if the memory provided > + * falls within boot memory area. > + */ > +int is_fadump_boot_memory_area(u64 addr, ulong size) > +{ > + if (!fw_dump.dump_registered) > + return 0; > + > + return (addr + size) > RMA_START && addr <= fw_dump.boot_memory_size; > +} > + > int is_fadump_active(void) > { > return fw_dump.dump_active; > diff --git a/arch/powerpc/platforms/pseries/hotplug-memory.c > b/arch/powerpc/platforms/pseries/hotplug-memory.c > index e104c71..a186b8e 100644 > --- a/arch/powerpc/platforms/pseries/hotplug-memory.c > +++ b/arch/powerpc/platforms/pseries/hotplug-memory.c > @@ -22,6 +22,7 @@ > #include > #include > #include > +#include > #include "pseries.h" > > static bool rtas_hp_event; > @@ -406,6 +407,12 @@ static bool lmb_is_removable(struct of_drconf_cell *lmb) > scns_per_block = block_sz / MIN_MEMORY_BLOCK_SIZE; > phys_addr = lmb->base_addr; > > +#ifdef CONFIG_FA_DUMP > + /* Don't hot-remove memory that falls in fadump boot memory area */ > + if (is_fadump_boot_memory_area(phys_addr, block_sz)) > + return false; > +#endif > + > for (i = 0; i < scns_per_block; i++) { > pfn = PFN_DOWN(phys_addr); > if (!pfn_present(pfn)) > >