From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mike Rapoport Date: Thu, 31 Jan 2019 06:41:39 +0000 Subject: Re: [PATCH v2 19/21] treewide: add checks for the return value of memblock_alloc*() Message-Id: <20190131064139.GB28876@rapoport-lnx> List-Id: References: <1548057848-15136-1-git-send-email-rppt@linux.ibm.com> <1548057848-15136-20-git-send-email-rppt@linux.ibm.com> In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable To: Christophe Leroy Cc: Rich Felker , linux-ia64@vger.kernel.org, Petr Mladek , linux-sh@vger.kernel.org, Catalin Marinas , Heiko Carstens , linux-kernel@vger.kernel.org, Max Filippov , Guo Ren , sparclinux@vger.kernel.org, Christoph Hellwig , linux-s390@vger.kernel.org, linux-c6x-dev@linux-c6x.org, Yoshinori Sato , Richard Weinberger , x86@kernel.org, Russell King , kasan-dev@googlegroups.com, Geert Uytterhoeven , Mark Salter , Dennis Zhou , Matt Turner , linux-snps-arc@lists.infradead.org, uclinux-h8-devel@lists.sourceforge.jp, devicetree@vger.kernel.org, Stephen Rothwell , linux-xtensa@linux-xtensa.org, linux-um@lists.infradead.org, linux-m68k@lists.linux-m68k.org, Rob Herring , Greentime Hu , xen-devel@lists.xenproject.org, Stafford Horne , Guan Xuetao , linux-arm-kernel@lists.infradead.org, Michal Simek , Tony Luck , linux-mm@kvack.org, Greg Kroah-Hartman , linux-usb@vger.kernel.org, linux-mips@vger.kernel.org, Paul Burton , Vineet Gupta , linux-alpha@vger.kernel.org, Andrew Morton , linuxppc-dev@lists.ozlabs.org, "David S. Miller" , openrisc@lists.librecores.org On Thu, Jan 31, 2019 at 07:07:46AM +0100, Christophe Leroy wrote: >=20 >=20 > Le 21/01/2019 =E0 09:04, Mike Rapoport a =E9crit=A0: > >Add check for the return value of memblock_alloc*() functions and call > >panic() in case of error. > >The panic message repeats the one used by panicing memblock allocators w= ith > >adjustment of parameters to include only relevant ones. > > > >The replacement was mostly automated with semantic patches like the one > >below with manual massaging of format strings. > > > >@@ > >expression ptr, size, align; > >@@ > >ptr =3D memblock_alloc(size, align); > >+ if (!ptr) > >+ panic("%s: Failed to allocate %lu bytes align=3D0x%lx\n", __func__, > >size, align); > > > >Signed-off-by: Mike Rapoport > >Reviewed-by: Guo Ren # c-sky > >Acked-by: Paul Burton # MIPS > >Acked-by: Heiko Carstens # s390 > >Reviewed-by: Juergen Gross # Xen > >--- >=20 > [...] >=20 > >diff --git a/mm/sparse.c b/mm/sparse.c > >index 7ea5dc6..ad94242 100644 > >--- a/mm/sparse.c > >+++ b/mm/sparse.c >=20 > [...] >=20 > >@@ -425,6 +436,10 @@ static void __init sparse_buffer_init(unsigned long= size, int nid) > > memblock_alloc_try_nid_raw(size, PAGE_SIZE, > > __pa(MAX_DMA_ADDRESS), > > MEMBLOCK_ALLOC_ACCESSIBLE, nid); > >+ if (!sparsemap_buf) > >+ panic("%s: Failed to allocate %lu bytes align=3D0x%lx nid=3D%d from= =3D%lx\n", > >+ __func__, size, PAGE_SIZE, nid, __pa(MAX_DMA_ADDRESS)); > >+ >=20 > memblock_alloc_try_nid_raw() does not panic (help explicitly says: Does n= ot > zero allocated memory, does not panic if request cannot be satisfied.). "Does not panic" does not mean it always succeeds. =20 > Stephen Rothwell reports a boot failure due to this change. Please see my reply on that thread. > Christophe >=20 > > sparsemap_buf_end =3D sparsemap_buf + size; > > } > > >=20 --=20 Sincerely yours, Mike.